ARQULE INC
10-Q, 1997-08-12
PHARMACEUTICAL PREPARATIONS
Previous: SEACHANGE INTERNATIONAL INC, 10-Q, 1997-08-12
Next: ACNIELSEN CORP, 10-Q, 1997-08-12



<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549


                                    FORM 10-Q

                Quarterly report pursuant to Section 13 or 15(d)
                     of the Securities Exchange Act of 1934


For the Quarter Ended June 30, 1997                Commission File No. 000-21429


                                  ARQULE, INC.
             (Exact Name of Registrant as Specified in its Charter)


         DELAWARE                                     04-3221586
(State of Incorporation)                 (I.R.S. Employer Identification Number)


                 200 BOSTON AVENUE, MEDFORD, MASSACHUSETTS 02155
                    (Address of Principal Executive Offices)


                                 (617) 395-4100
              (Registrant's Telephone Number, including Area Code)


Indicate by check mark whether the registrant: (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.

YES             X*                        NO
   -----------------------------            -----------------------------

Number of shares outstanding of the registrant's Common Stock as of 
August 6, 1997:

<TABLE>
<S>                                         <C>                          
Common Stock, par value $.01                11,846,222 shares outstanding
</TABLE>


*    The Company has been subject to such filing requirements since its
     Registration Statement Number 333-11105 on Form S-1 was declared effective
     on October 16, 1996.
<PAGE>   2
                                  ARQULE, INC.

                           QUARTER ENDED JUNE 30, 1997


                                TABLE OF CONTENTS



PART I - FINANCIAL INFORMATION                                             PAGE
                                                                           ----
Item 1 - Unaudited Condensed Financial Statements

       Condensed Balance Sheet (Unaudited)
           June 30, 1997 and December 31, 1996 ...........................    2

       Condensed Statement of Operations (Unaudited)
           Three months ended June 30, 1997 and 1996
           and six months ended June 30, 1997 and 1996....................    3

       Condensed Statement of Cash Flows (Unaudited)
           Six months ended June 30, 1997 and 1996........................    4

       Notes to Unaudited Condensed Financial Statements..................    5

Item 2 - Management's Discussion and Analysis of
           Financial Condition and Results of Operations..................    8


PART II - OTHER INFORMATION...............................................   12

Item 4 - Submission of Matters to a Vote of Security Holders..............   12

Item 6 - Exhibits and Reports on Form 8-K.................................   12

Signatures................................................................   13
<PAGE>   3
                                  ARQULE, INC.

                       CONDENSED BALANCE SHEET (UNAUDITED)
                       (IN THOUSANDS, EXCEPT SHARE DATA)

<TABLE>
<CAPTION>
                                                                                   JUNE 30,       DECEMBER 31,
                                                                                     1997             1996
                                                                                 ------------     ------------
<S>                                                                              <C>              <C>
ASSETS
Current Assets:
       Cash and cash equivalents                                                    $12,488         $36,586
       Marketable securities                                                         40,593             500
       Accounts receivable                                                            1,446             250
       Prepaid expenses and other current assets                                        113             338
       Notes receivable from related parties                                            176             176
                                                                                    -------         -------
                                                                                   
             Total current assets                                                    54,816          37,850

       Property and equipment, net                                                    7,318           5,293
       Other assets                                                                     153             139
       Notes receivable from related parties                                            212             227
                                                                                    -------         -------

                                                                                    $62,499         $43,509
                                                                                    =======         =======
LIABILITIES AND STOCKHOLDERS' EQUITY 
       Current liabilities:
       Current portion of capital lease obligations                                 $ 1,373         $ 1,138
       Accounts payable and accrued expenses                                          1,394           1,109
       Deferred revenue                                                               1,495           4,163
                                                                                    -------         -------

            Total current liabilities                                                 4,262           6,410
                                                                             
Capital lease obligations                                                             1,700           1,728

Deferred revenue                                                                        795             750

Stockholders' Equity:
       Common Stock, $0.01 par value; 30,000,000 shares 
            authorized; 11,807,012 and 9,851,487 shares
            issued and outstanding at June 30, 1997 and
            December 31, 1996, respectively                                             118              99
       Additional paid-in capital                                                    68,040          46,102
       Accumulated deficit                                                          (11,664)        (10,934)
                                                                                    -------         -------
                                                                                     56,494          35,267
Deferred compensation                                                                  (752)           (646)
                                                                                    -------         -------
       Total stockholders' equity                                                    55,742          34,621
                                                                                    -------         -------
                                                                                    $62,499         $43,509
                                                                                    =======         =======
</TABLE>


                                      -2-
<PAGE>   4
                                  ARQULE, INC.

                  CONDENSED STATEMENT OF OPERATIONS (UNAUDITED)
                      (IN THOUSANDS, EXCEPT PER SHARE DATA)

<TABLE>
<CAPTION>
                                                     THREE MONTHS ENDED       SIX MONTHS ENDED
                                                          JUNE 30,                JUNE 30,
                                                      1997        1996        1997        1996
                                                    --------    --------    --------    --------
<S>                                                 <C>         <C>         <C>         <C>
Revenue:
     Compound development revenue                   $  2,364    $    800    $  4,728    $  1,475
     Compound development revenue - related party        895         750       1,790       1,500
                                                    --------    --------    --------    --------
          Total revenue                                3,259       1,550       6,518       2,975

Costs and expenses:
     Cost of revenue                                   1,609         552       3,073         962
     Cost of revenue - related party                     635         589       1,253         973
     Research and development                          1,158         579       1,828       1,119
     Marketing, general and administrative               924         515       2,097         828
                                                    --------    --------    --------    --------
          Total costs and expenses                     4,326       2,235       8,251       3,882
                                                    --------    --------    --------    --------

          Loss from operations                        (1,067)       (685)     (1,733)       (907)

Interest income                                          702          83       1,146         172
Interest expense                                         (70)         14        (143)        (19)
                                                    --------    --------    --------    --------

          Net loss                                  $   (435)   $   (588)   $   (730)   $   (754)
                                                    ========    ========    ========    ========

Net loss per share (pro forma for 1996)             $  (0.04)   $  (0.08)   $  (0.07)   $  (0.10)
                                                    ========    ========    ========    ========

Weighted average common shares outstanding            11,591       7,438      10,724       7,443
     (pro forma for 1996)                           ========    ========    ========    ========
</TABLE>


                                      -3-
<PAGE>   5
                                  ARQULE, INC.
                  CONDENSED STATEMENT OF CASH FLOWS (UNAUDITED)
                INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS

<TABLE>
<CAPTION>
                                                               SIX MONTHS ENDED
                                                                   JUNE 30,
                                                               1997        1996
                                                             --------    --------
<S>                                                          <C>         <C>
Cash flows from operating activities:
     Net loss                                                $   (730)   $   (754)
Adjustment to reconcile net loss to net cash provided
     by operating activities:
     Depreciation and amortization                              1,007         434
     Amortization of deferred compensation                        224          --
     Increase in accounts receivable                           (1,196)         --
     Decrease in prepaid expenses and other current assets        225          43
     Increase in other assets                                     (14)         --
     Decrease in notes receivable from related party               15          --
     Increase in accounts payable and accrued expenses            285         550
     (Decrease) increase in deferred revenue                   (2,623)      1,025
                                                             --------    --------

Net cash (used in) provided by operating activities            (2,807)      1,298
                                                             --------    --------

Cash flows from investing activities:
      Purchase of available-for-sale marketable securities    (40,093)         --
      Proceeds from sale or maturity of available-for-sale
          marketable securities                                    --       1,002
      Proceeds from issuance of Common Stock                   21,627          --
      Additions to property and equipment                      (2,209)     (2,437)
                                                             --------    --------

Net cash used in investing activities                         (20,675)     (1,435)
                                                             --------    --------

Cash flows from financing activities:
     Principal payments of capital lease obligation              (616)       (285)
                                                             --------    --------

Net cash used in financing activities                            (616)       (285)
                                                             --------    --------

Net decrease in cash and cash equivalents                     (24,098)       (422)
Cash and cash equivalents, beginning of period                 36,586       2,989
                                                             --------    --------

Cash and cash equivalents, end of period                     $ 12,488    $  2,567
                                                             ========    ========
</TABLE>


                                      -4-
<PAGE>   6
                                  ARQULE, INC.
                NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS



1.     BASIS OF PRESENTATION

       The accompanying unaudited condensed financial statements have been
       prepared by the Company without audit, pursuant to the rules and
       regulations of the Securities and Exchange Commission. Certain
       information and footnote disclosures normally included in financial
       statements prepared in accordance with generally accepted accounting
       principles have been condensed or omitted pursuant to such rules and
       regulations. These condensed financial statements should be read in
       conjunction with the Company's audited financial statements and related
       footnotes for the year ended December 31, 1996 thereto included in the
       Company's Form 10-K filed with the Securities and Exchange Commission on
       March 31,1997. The unaudited condensed financial statements include, in
       the opinion of management, all adjustments (consisting only of normal
       recurring adjustments) necessary to present fairly the financial position
       of ArQule, Inc. as of June 30, 1997, and the results of its operations
       for the three and six month periods ending June 30, 1997 and 1996. The
       results of operations for such interim periods are not necessarily
       indicative of the results to be achieved for the full year.

2.     NET LOSS PER SHARE (UNAUDITED)

       Pro forma net loss per share is determined by dividing the net loss by
       the weighted average number of shares of Common Stock and common stock
       equivalents outstanding during the period, assuming the conversion of all
       convertible preferred stock which occurred upon the closing of the public
       offering of the Company's Common Stock on October 16, 1996.

       Common Stock equivalents, although anti-dilutive, issued at prices below
       the offering price per share during the twelve month period preceding the
       initial filing of the Company's Registration Statement Commission File
       Number 333-11105 have been included in the calculation of pro forma net
       loss per share using the treasury stock method and the initial public
       offering price of $12.00 per share as if outstanding for all periods
       presented through June 30, 1996.

       Historical net loss per share has not been presented for the three and
       six months ended June 30, 1996 as the Series A Convertible Preferred
       Stock would have been omitted from the weighted average shares
       outstanding as it is anti-dilutive and was issued more than twelve months
       prior to the public offering.


                                      -5-
<PAGE>   7
                                  ARQULE, INC.

          NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS (CONTINUED)



       In February 1997, the Financial Accounting Standards Board issued
       Statement of Financial Accounting Standards No. 128 ("SFAS 128"),
       "Earnings Per Share." SFAS 128 will be effective for the Company's fourth
       quarter of 1997 and requires the restatement of all previously reported
       earnings per share data that are presented. Early adoption of SFAS 128 is
       not permitted. SFAS 128 replaces primary and fully diluted earnings per
       share with basic and diluted earnings per share. As the Company has
       historically reported net losses, earnings per share as computed under
       the provisions of SFAS 128 is not expected to differ from the earnings
       per share amounts previously reported by the Company.

3.     FOLLOW-ON OFFERING OF COMMON STOCK (UNAUDITED)

       On April 4, 1997, the Company completed a follow-on offering of 1,932,500
       shares of Common Stock at $12.00 per share, which included the
       underwriters' exercise of their over-allotment option of 300,000 shares
       of Common Stock on April 14, 1997. The combined gross proceeds raised by
       ArQule from the offering and over-allotment option was approximately
       $23,190,000.


4.     CASH EQUIVALENTS AND MARKETABLE SECURITIES (UNAUDITED)

       The following is a summary of cash equivalents held by the Company at
       June 30, 1997 and December 31, 1996 which are carried at fair market
       value: (In thousands)

<TABLE>
<CAPTION>
                                                         JUNE 30,      DECEMBER 31,
                                                           1997            1996
- -----------------------------------------------------------------------------------
<S>                                                      <C>           <C>    
Money Market                                             $ 5,834         $36,126
U.S. Government Debt Securities                            1,584              --
Corporate Notes                                            4,488              --
                                                         -------         -------
                                                         $11,906         $36,126
                                                         =======         =======
</TABLE>


                                      -6-
<PAGE>   8
                                  ARQULE, INC.

          NOTES TO UNAUDITED CONDENSED FINANCIAL STATEMENTS (CONTINUED)



       The following is a summary of available-for-sale marketable securities
       held by the Company at June 30, 1997 and December 31, 1996 which are
       carried at fair market value: (In thousands)

<TABLE>
<CAPTION>
                                                              UNREALIZED    UNREALIZED    AMORTIZED
JUNE 30, 1997                MATURITY TERM      FAIR VALUE       GAINS        LOSSES        COST
- ----------------------------------------------------------------------------------------------------
<S>                          <C>                <C>           <C>           <C>           <C>
U.S. Government                                                            
   Debt Securities           Within 1 year        $13,744          1           (1)        $13,744
                                                                                          
Corporate Notes              Within 1 year         26,849          3           (3)         26,849
                                                  -------         --          ---         -------
                                                                                          
                                                  $40,593          4           (4)        $40,593
                                                  =======         ==          ===         =======
</TABLE>                                                                

<TABLE>
<CAPTION>
DECEMBER 31, 1996
- --------------------------------------------------------------------------------
<S>                          <C>                <C>       <C>    <C>     <C>
U.S. Government
   Debt Securities           Within 1 year      $500       --     --     $500
                                                ----      ---    ---     ----

                                                $500       --     --     $500
                                                ====      ===    ===     ====
</TABLE>

       All of the Company's marketable securities are classified as current at
       June 30, 1997 and December 31, 1996 as these funds are highly liquid and
       are available to meet working capital needs and to fund current
       operations.

5.     SUBSEQUENT EVENT (UNAUDITED)

       On July 3, 1997, the Company and Wyeth-Ayerst Pharmaceuticals, a division
       of American Home Products Corporation, signed a collaboration to discover
       and optimize drug candidates for a minimum of 15 of Wyeth-Ayerst's
       selected pharmaceutical targets. Wyeth-Ayerst will pay ArQule
       approximately $28 million, which includes a $2 million equity investment
       in ArQule to be paid in 1998. Wyeth-Ayerst will make further payments to
       ArQule throughout the five year collaboration as development milestones
       are reached. In addition, ArQule will be entitled to royalties from sales
       of any products emanating from this collaboration. On July 3, 1997, under
       the terms of the agreement, Wyeth made an initial payment to the Company
       of $2.3 million upon commencement of the collaboration. The 5 year
       collaboration will provide Wyeth-Ayerst with access to ArQule's Mapping
       Array(TM) Program as well as access to ArQule's Directed Array(TM)
       Program.


                                      -7-
<PAGE>   9
                                  ARQULE, INC.
           MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION
                            AND RESULTS OF OPERATION

OVERVIEW

       ArQule is engaged in the discovery and development of novel chemical
       compounds with commercial potential in the pharmaceutical, biotechnology
       and agrichemical industries. ArQule manufactures and delivers two types
       of arrays of synthesized compounds to its pharmaceutical, biotechnology
       and agrichemical partners: (i) Mapping Array(TM) compound sets, which are
       arrays of novel, diverse small molecule compounds used for generating
       leads and (ii) Directed Array(TM) compound sets, which are arrays of
       analogs of a particular lead compound (identified from a Mapping Array
       set or otherwise), synthesized for the purpose of optimizing such lead
       compounds.

       The Company currently generates revenue primarily through compound
       development from collaborative agreements, which provide for the
       development and delivery of Mapping Array(TM) and Directed Array(TM)
       sets. The Company's revenue to date is primarily attributable to five
       major corporate collaborations: Pharmacia Biotech AB, entered into in
       March 1995; Abbott Laboratories, entered into in June 1995; Solvay Duphar
       B.V., entered into in November 1995; Roche Bioscience, entered into in
       September 1996; and Monsanto Company, entered into in December 31, 1996.
       Under these collaborations, the Company has received payments of $17.8
       million through June 30, 1997 and has recognized $16.9 million as
       revenue. The Company recognizes revenue under its corporate
       collaborations as related work is performed and arrays are delivered.
       Payments received from corporate partners prior to the completion of the
       related work are recorded as deferred revenue. The Company is also
       entitled to receive milestone and royalty payments if products generated
       under the collaborations are developed. The Company has not received any
       milestone or royalty payments to date. The Company has additionally
       entered into joint discovery agreements with a number of biotechnology
       companies to which it has provided Mapping Array(TM) and Directed
       Array(TM) sets in exchange for joint ownership of resulting drug
       candidates. These arrangements have not yet yielded any significant
       revenue for the Company.

       The Company has not been profitable since incorporation and has incurred
       a cumulative net loss of $11.7 million through June 30, 1997. Losses have
       resulted principally from costs incurred in research and development
       activities related to the Company's efforts to develop its technologies
       and from the associated administrative costs required to support those
       efforts. The Company's ability to achieve profitability is dependent on
       its ability to market its Mapping Array(TM) and Directed Array(TM)
       programs to pharmaceutical, biotechnology and agrichemical companies and
       the joint development and commercialization of products in which it has
       an economic interest.


                                      -8-
<PAGE>   10
       This Management's Discussion and Analysis of Financial Condition and
       Results of Operations contains forward-looking statements reflecting
       management's current expectations regarding the Company's future
       financial performance. Such expectations are based on certain assumptions
       regarding the progress of product development efforts under collaborative
       agreements, the execution of new collaborative agreements and other
       factors relating to the Company's growth. Such expectations may not
       materialize if product development efforts are delayed or suspended, if
       negotiations with potential collaborators are delayed or unsuccessful or
       if other assumptions prove incorrect. See also "Important Factors
       Regarding Forward-Looking Statements" described more fully in the
       Company's Annual Report on Form 10K for the year ended December 31, 1996.


RESULTS OF OPERATIONS

     THREE AND SIX MONTHS ENDED JUNE 30, 1997 AND 1996

       REVENUE. The Company's revenue for the three months ended June 30, 1997
       increased $1.7 million to $3.3 million from $1.6 million for the same
       period in 1996. Revenue was $6.5 million and $3.0 million for the six
       months ended June 30, 1997 and 1996, respectively. The increase is
       primarily due to increased compound development revenue from work
       performed on and the delivery of Mapping Array(TM) and Directed Array(TM)
       sets under the Company's collaborative agreements. The increase is
       primarily attributable to the addition of collaborative agreements with
       Roche BioScience and Monsanto Company in October and December of 1996,
       respectively.

       COST OF REVENUE. The Company's cost of revenue for the three months ended
       June 30, 1997 increased $1.1 million to $2.2 million from $1.1 million
       for the same period in 1996. Cost of revenue was $4.3 million and $1.9
       million for the six months ended June 30, 1997 and 1996, respectively.
       The increase is primarily attributable to the costs of additional
       scientific and facilities personnel and the necessary supplies and
       overhead expenses related to the performance of the work and the delivery
       of the Mapping Array(TM) and Directed Array(TM) sets pursuant to the
       Company's collaborative agreements. The Company anticipates that the
       aggregate cost of revenue will increase over the next several years as
       its business expands.

       RESEARCH AND DEVELOPMENT EXPENSES. The Company's research and development
       expenses for the three months ended June 30, 1997 increased $0.6 million
       to $1.2 million from $0.6 million for the same period in 1996. Research
       and development expenses were $1.8 million and $1.1 million for the six
       months ended June 30, 1997 and 1996, respectively. The increase is the
       result of the Company's expansion of its chemical libraries and related
       proprietary technologies. The Company expects research and development
       spending to increase over the next several years as the Company further
       expands its chemistry discovery and development programs.


                                      -9-
<PAGE>   11
       MARKETING, GENERAL AND ADMINISTRATIVE EXPENSES. The Company's marketing,
       general and administrative expenses for the three months ended June 30,
       1997 increased $0.4 million to $0.9 million from $0.5 million for the
       same period in 1996. Marketing, general and administrative expenses were
       $2.1 million and $0.8 million for the six months ended June 30, 1997 and
       1996, respectively. The increase is primarily associated with increased
       marketing and business development activities, expenses of being a
       public company, and higher levels of administrative support for the
       Company's growth during 1997. These expenses will likely increase in the
       aggregate in future periods to support the projected growth of the
       Company.

       NET INTEREST INCOME (EXPENSE). The Company's net interest income for the
       three months ended June 30, 1997 was $0.6 million, which compared to $0.1
       million for the same period in 1996. Net income was $1.0 million and $0.2
       million for the six months ended June 30, 1997 and 1996, respectively.
       Higher interest income in 1997 resulted primarily from the Company
       holding higher cash and marketable securities balances following its
       initial and follow-on offerings of Common Stock in October 1996 and April
       of 1997, respectively.

       NET LOSS. The Company's net loss for the three months ended June 30, 1997
       decreased $0.2 million to $0.4 million from $0.6 million for the same
       period in 1996. Net loss was $0.7 million and $0.8 million for the six
       months ended June 30, 1997 and 1996, respectively. The decrease is
       primarily attributable to expanded levels of research and operating
       expenses which were partially offset by the increase in net interest
       income.



LIQUIDITY AND CAPITAL RESOURCES

       At June 30, 1997, the Company held cash and cash equivalents and
       marketable securities with a value of $53.1 million. The Company's
       working capital at June 30, 1997 was $50.6 million. The Company has
       funded operations through June 30, 1997 with sales of preferred stock and
       Common Stock totaling $66.8 million, payments from corporate
       collaborators totaling $17.8 million, and the utilization of capital
       equipment lease financing totaling $5.0 million. The Company has
       maintained a master lease agreement since February 1994. Under the terms
       of this agreement, the Company has funded certain capital expenditures
       through leases with terms of 42 months in duration. As of June 30, 1997,
       the Company had utilized $4.4 million of the available $8.5 million
       financing facility.

       In April 1997, the Company raised gross proceeds of approximately $23.2
       million from the sale of 1.9 million shares of Common Stock in the
       Company's follow-on offering.

       Management estimates that the Company's existing cash equivalents,
       short-term investments, cash generated from operations and research
       funding from corporate collaborators will enable the Company to maintain
       its current and planned operations


                                      -10-
<PAGE>   12
     at least through March 1999. The Company's cash requirements may vary
     materially from those now planned depending upon the results of its drug
     discovery and development strategies, the ability of the Company to enter
     into any corporate collaborations in the future and the terms of such
     collaborations, the results of research and development, the need for
     currently unanticipated capital expenditures, competitive and technological
     advances, acquisitions and other factors. There can be no assurance that
     the Company will be able to obtain additional customers for the Company's
     products and services, or that such products and services will produce
     revenues adequate to fund the Company's operating expenses. If the Company
     experiences increased losses, the Company may have to seek additional
     financing from public or private sale of its securities, including equity
     securities. There can be no assurance that additional funding will be
     available when needed or on acceptable terms.


                                      -11-
<PAGE>   13

                                  ARQULE, INC.




PART II - OTHER INFORMATION

Items 1 - 3 - None

Item 4: - Submission of Matters to a Vote of Security Holders

         At the Annual Meeting of stockholders held on May 14, 1997, the
         Company's stockholders voted to re-elect Messrs. Stephen M. Dow and
         Eric B. Gordon to the Board of Directors each for a three-year term.

<TABLE>
<CAPTION>
         Nominees             Total Vote "For"     Total Vote "Against"
         --------------------------------------------------------------
         <S>                  <C>                  <C>  
         Stephen M. Dow          7,194,185               9,600
         Eric B. Gordon          7,172,935              30,850
</TABLE>

         The terms in office of Allan R. Ferguson, Joseph C. Hogan, Jr., Ph.D. 
         and Adrian deJonge, Ph.D. continued after the meeting.

Item 5 - None

Item 6(a) - Exhibit:

<TABLE>
<CAPTION>
      Exhibits                             Description
      --------                             -----------
      <S>                    <C>
        10.1:                Research and License Agreement between the
                             Company and American Home Products Corporation
                             acting through its Wyeth-Ayerst Research Division,
                             dated July 3, 1997.

        10.2:                Common Stock Purchase Agreement between the Company
                             and American Home Products Corporation dated 
                             July 3, 1997

        11:                  Statement Regarding Computation of Unaudited Pro 
                             Forma Net Loss Per Share

        27:                  Financial Data Schedule
</TABLE>

Item 6(b) - Reports On Form 8-K

         No reports on Form 8-K have been filed during the quarter for which
         this report is filed.


                                      -12-
<PAGE>   14
                                  ARQULE, INC.




                                   SIGNATURES



Pursuant to the requirements of the Securities Act of 1934, the registrant has
duly caused this report to be signed on its behalf by the undersigned thereunto
duly authorized.


                                 ArQule, Inc.






Date:  August 11, 1997           /s/ James R. Fitzgerald, Jr.
                                 -----------------------------------------------
                                 James R. Fitzgerald, Jr.
                                 (Vice President, Chief Financial Officer and 
                                 Treasurer)


                                      -13-
<PAGE>   15
                                  ARQULE, INC.
                                 EXHIBIT INDEX



EXHIBIT NO.                         DESCRIPTION
- -----------                         -----------
   
   10.1++:      Research and License Agreement between the Company and 
                American Home Products Corporation acting through its
                Wyeth-Ayerst Research Division, dated July 3, 1997.

   10.2:        Common Stock Purchase Agreement between the Company and 
                American Home Products Corporation dated July 3, 1997

   11:          Statement Regarding Computation of Unaudited Pro Forma Net 
                Loss Per Share

   27:          Financial Data Schedule







++   Confidential treatment has been requested for certain portions of this
     Exhibit persuant to Rule 24b-2 of the Securities Exchange Act of 1934, as
     amended.


                                      -14-

<PAGE>   1
                         RESEARCH AND LICENSE AGREEMENT

                                     between

                                  ARQULE, INC.

                                       and

                       AMERICAN HOME PRODUCTS CORPORATION

                               acting through its

                         WYETH-AYERST RESEARCH DIVISION

                            dated as of July 3, 1997



<PAGE>   2



                                TABLE OF CONTENTS
                                                                           PAGE
                                                                           ----

1.  DEFINITIONS............................................................  1
    -----------
    1.1.     "ACTIVE HOMOLOG"..............................................  1
              --------------
    1.2.     "ACTIVE ARQULE COMPOUND"......................................  1
              ----------------------
    1.3.     "ACTIVE COMPOUND".............................................  1
              ---------------
    1.4.     "ACTIVE WYETH-AYERST COMPOUND"................................  1
              ----------------------------
    1.5.     "AFFILIATE"...................................................  2
              ---------
    1.6.     "AGREEMENT"...................................................  2
              ---------
    1.7.     "ARQULE COMPOUND".............................................  2
              ---------------
    1.8.     "ARQULE DERIVATIVE COMPOUND"..................................  2
              --------------------------
    1.9.     "ARQULE INTERNAL DEVELOPMENT PROGRAM".........................  2
              -----------------------------------
    1.10.    "ARQULE PATENT RIGHTS"........................................  2
              --------------------
    1.11.    "ARQULE TECHNOLOGY............................................  2
              -----------------
    1.12.    "ARRAY".......................................................  2
              -----
    1.13.    "CHEMICAL THEME"..............................................  2
              --------------
    1.14.    "CONFIDENTIAL INFORMATION"....................................  2
              ------------------------
    1.15.    "CONTRACT YEAR"...............................................  2
              -------------
    1.16.    "DERIVATIVE COMPOUND".........................................  3
              -------------------
    1.17.    "DIRECTED ARRAY(TM)"..........................................  3
              ------------------
    1.18.    "DIRECTED ARRAY(TM) PROGRAM"..................................  3
              --------------------------
    1.19.    "DISCLOSING PARTY"............................................  3
              ----------------
    1.20.    "EFFECTIVE DATE"..............................................  3
              --------------
    1.21.    "EXTRAORDINARY EXPENSES"......................................  3
              ----------------------
    1.22.    "FDA".........................................................  3
              ---
    1.24.    "IND-TRACK STATUS"............................................  3
              ----------------
    1.25.    "JOINT PATENT RIGHTS".........................................  3
              -------------------
    1.26.    "LICENSED COMPOUND"...........................................  3
              -----------------
    1.27.    "LICENSED COMPOUND SET".......................................  3
              ---------------------
    1.28.    "MAJOR MARKET COUNTRY"........................................  4
              --------------------
    1.29.    "MAPPING ARRAY(TM)"...........................................  4
              -----------------
    1.30.    "MAPPING ARRAY(TM) PROGRAM"...................................  4
              -------------------------
    1.31.    "NET SALES"...................................................  4
              ---------
    1.32.    "NET SALES PRICE".............................................  4
              ---------------
    1.33.    "PARTY".......................................................  5
              -----
    1.34.    "PATENT RIGHTS"...............................................  5
              -------------
    1.35.    "PHASE I CLINICAL TRIALS".....................................  5
              -----------------------
    1.36.    "PHASE II CLINICAL TRIALS"....................................  5
              ------------------------
    1.37.    "PHASE III CLINICAL TRIALS"...................................  5
              -------------------------
    1.38.    "PRECLINICAL COMPOUND"........................................  5
              --------------------
    1.39.    "PRECLINICAL DEVELOPMENT".....................................  5
              -----------------------
    1.40.    "RECEIVING PARTY".............................................  6
              ---------------
    1.41.    "RESEARCH PERIOD".............................................  6
              ---------------
    1.42.    "RESEARCH PLAN"...............................................  6
              -------------

                                     (i)

<PAGE>   3




    1.43.    "RESEARCH PROGRAM"............................................  6
              ----------------
    1.44.    "ROYALTY-BEARING PRODUCT".....................................  6
              -----------------------
    1.45.    "ROYALTY PERIOD"..............................................  6
              --------------
    1.46.    "RESEARCH COMMITTEE"..........................................  6
              ------------------
    1.47.    "SUBLICENSEE..................................................  6
              -----------
    1.48.    "TARGET"......................................................  6
              ------
    1.49.    "WYETH-AYERST COMPOUND".......................................  6
              ---------------------
    1.50.    "WYETH-AYERST DERIVATIVE COMPOUND.............................  6
              --------------------------------
    1.51.    "WYETH-AYERST PATENT RIGHTS"..................................  6
              --------------------------

2.  MANAGEMENT OF RESEARCH PROGRAM.........................................  7
    ------------------------------
    2.1.     COMPOSITION OF RESEARCH COMMITTEE.............................  7
             ---------------------------------
    2.2.     DUTIES OF THE RESEARCH COMMITTEE..............................  7
             --------------------------------
    2.3.     MEETINGS OF THE RESEARCH COMMITTEE............................  8
             ----------------------------------
    2.4.     COOPERATION...................................................  8
             -----------
    2.5.     VISITS TO FACILITIES..........................................  8
             --------------------

3.  MAPPING ARRAY(TM) PROGRAM..............................................  8
    ------------------------
    3.1.     CONDUCT OF MAPPING ARRAY(TM) PROGRAM..........................  8
             ------------------------------------
    3.2.     MUTUAL DISCLOSURE.............................................  9
             -----------------
    3.3.     RESERVATION OF ACTIVE ARQULE COMPOUNDS........................  9
             --------------------------------------
    3.4.     MAPPING ARRAY(TM) PROGRAM PAYMENTS...........................  10
             ----------------------------------
    3.5.     TERM OF MAPPING ARRAY(TM) PROGRAM............................  10
             ---------------------------------
    3.6.     PERFORMANCE OF MAPPING ARRAY(TM) PROGRAM.....................  10
             ----------------------------------------

4.  DIRECTED ARRAY(TM) PROGRAM............................................  11
    --------------------------
    4.1.     DESCRIPTION OF DIRECTED ARRAY(TM) PROGRAM....................  11
             -----------------------------------------
    4.2.     COMPOUNDS EXCLUDED FROM THE DIRECTED ARRAY(TM) PROGRAM.......  12
             ------------------------------------------------------
    4.3.     CONDUCT OF DIRECTED ARRAY(TM) PROGRAM........................  12
             -------------------------------------
    4.4.     DIRECTED ARRAY(TM) PROGRAM PAYMENTS..........................  13
             -----------------------------------
                      4.4.1.  DELIVERY FEE................................  13
                              ------------
                      4.4.2.  EXPENSES....................................  13
                              --------
    4.5.     TERM OF DIRECTED ARRAY(TM) PROGRAMS..........................  14
             -----------------------------------
    4.6.     PERFORMANCE OF DIRECTED ARRAY(TM) PROGRAM....................  14
             -----------------------------------------

5.  LICENSE GRANTS; REVERSION OF RIGHTS...................................  14
    -----------------------------------
    5.1.     SCREENING LICENSES...........................................  14
             ------------------
    5.2.     COMMERCIALIZATION LICENSE....................................  14
             -------------------------
    5.3.     REVERSION OF RIGHTS; RETURN OF MATERIALS.....................  15
             ----------------------------------------
    5.4.     DIRECT LICENSES TO AFFILIATES................................  15
             -----------------------------

6.  OWNERSHIP OF COMPOUNDS................................................  16
    ----------------------
    6.1.     WYETH-AYERST COMPOUNDS; WYETH-AYERST DERIVATIVE COMPOUNDS....  16
             ---------------------------------------------------------
    6.2.     ARQULE COMPOUNDS; ARQULE DERIVATIVE COMPOUNDS................  16
             ---------------------------------------------



                                      (ii)

<PAGE>   4




7.  INTELLECTUAL PROPERTY RIGHTS..........................................  16
    ----------------------------
    7.1.     OWNERSHIP OF PATENT RIGHTS...................................  16
             --------------------------
    7.2.     MANAGEMENT OF JOINT PATENT RIGHTS............................  17
             ---------------------------------
    7.3.     COOPERATION OF THE PARTIES...................................  17
             --------------------------
    7.4.     INFRINGEMENT BY THIRD PARTIES................................  17
             -----------------------------
    7.5.     INFRINGEMENT OF THIRD PARTY RIGHTS...........................  18
             ----------------------------------
    7.6.     TRADEMARKS...................................................  19
             ----------

8.  PAYMENTS, REPORTS, AND RECORDS........................................  19
    ------------------------------
    8.1.     ACCESS FEE...................................................  19
             ----------
    8.2.     RESEARCH AND DEVELOPMENT PAYMENTS............................  19
             ---------------------------------
    8.3.     MARGINAL ROYALTIES...........................................  20
             ------------------
    8.4.     REPORTS AND PAYMENTS.........................................  21
             --------------------
    8.5.     INVOICES; PAYMENTS IN U.S. DOLLARS...........................  21
             ----------------------------------
    8.6.     PAYMENTS IN OTHER CURRENCIES.................................  21
             ----------------------------
    8.7.     RECORDS......................................................  22
             -------
    8.8.     TERM OF ROYALTY OBLIGATION...................................  22
             --------------------------
    8.9.     THIRD PARTY ROYALTIES........................................  22
             ---------------------


9.  CONFIDENTIAL INFORMATION..............................................  22
    ------------------------
    9.1.     DEFINITION OF CONFIDENTIAL INFORMATION.......................  22
             --------------------------------------
    9.2.     DESIGNATION OF CONFIDENTIAL INFORMATION......................  23
             ---------------------------------------
    9.3.     OBLIGATIONS..................................................  23
             -----------
    9.4.     EXCEPTIONS...................................................  23
             ----------
    9.5.     RETURN OF CONFIDENTIAL INFORMATION...........................  24
             ----------------------------------
    9.6.     PUBLICATIONS.................................................  24
             ------------
    9.7.     SURVIVAL OF OBLIGATIONS......................................  24
             -----------------------

10. REPRESENTATIONS AND WARRANTIES........................................  24
    ------------------------------
    10.1.    AUTHORIZATION................................................  24
             -------------
    10.2.    INTELLECTUAL PROPERTY........................................  24
             ---------------------

11. INDEMNIFICATION AND INSURANCE.........................................  25
    -----------------------------
    11.1.    WYETH-AYERST INDEMNITY OBLIGATIONS...........................  25
             ----------------------------------
    11.2.    CROSS-INDEMNITY OBLIGATIONS..................................  25
             ---------------------------
    11.3.    PROCEDURE....................................................  25
             ---------
    11.4.    INSURANCE....................................................  26
             ---------

12. TERM AND TERMINATION..................................................  26
    --------------------
    12.1.    TERM.........................................................  26
             ----
    12.2.    BREACH OF PAYMENT OBLIGATIONS................................  26
             -----------------------------
    12.3.    MATERIAL BREACH..............................................  26
             ---------------
    12.4.    INSOLVENCY...................................................  26
             ----------
    12.5.    CHANGE OF CONTROL............................................  27
             -----------------
    12.6.    EFFECT OF TERMINATION........................................  27
             ---------------------


                                    (iii)

<PAGE>   5



13. MISCELLANEOUS.........................................................  28
    -------------
    13.1.   RELATIONSHIP OF PARTIES.......................................  28
            -----------------------
    13.2.   PUBLICITY.....................................................  28
            ---------
    13.3.   GOVERNING LAW.................................................  28
            -------------
    13.4.   DISPUTE RESOLUTION PROCEDURES.................................  28
            -----------------------------
    13.5.   COUNTERPARTS..................................................  29
            ------------
    13.6.   HEADINGS......................................................  29
            --------
    13.7.   BINDING EFFECT................................................  29
            --------------
    13.8.   ASSIGNMENT....................................................  29
            ----------
    13.9.   NOTICES.......................................................  29
            -------
    13.10.  AMENDMENT AND WAIVER..........................................  30
            --------------------                            
    13.11.  SEVERABILITY..................................................  30
            ------------                                    
    13.12.  ENTIRE AGREEMENT..............................................  30
            ----------------                                
    13.13.  FORCE MAJEURE.................................................  30
            -------------                                   
    13.14.  HART-SCOTT-RODINO ACT.........................................  31
            ---------------------                           
                                                            
EXHIBIT A.................................................................  33
                                                            
EXHIBIT B.................................................................  34


                                      (iv)

<PAGE>   6





                         RESEARCH AND LICENSE AGREEMENT

     This Agreement, dated as of July 3, 1997, is between ArQule, Inc.
("ArQule"), a Delaware corporation, and American Home Products Corporation,
acting through its Wyeth-Ayerst Research division ("Wyeth-Ayerst"), a Delaware
corporation.


                                 R E C I T A L S
                                 - - - - - - - -

     WHEREAS, ArQule has developed certain technology that has applications in
the discovery and optimization of pharmaceutical compounds;

     WHEREAS, Wyeth-Ayerst desires that ArQule apply its technologies to the
research and optimization of pharmaceutical compounds for Wyeth-Ayerst; and

     WHEREAS, in exchange for payment by Wyeth-Ayerst of research funds and
royalties, ArQule is willing to perform certain research and compound
optimization activities for Wyeth-Ayerst, subject to the terms and conditions of
this Agreement;

     NOW, THEREFORE, in consideration of the mutual covenants set forth in this
Agreement, the Parties hereby agree as follows:


1. DEFINITIONS.

     1.1. "ACTIVE HOMOLOG" shall mean any ArQule Compound within the same
Chemical Theme as an Active ArQule Compound that exhibits substantial structural
homology with such Active ArQule Compound and exhibits minimal functional
activity. The criteria for determining "substantial structural homology" and
"minimal functional activity" for each Active ArQule Compound are established by
the Research Committee acting in accordance with Section 2.

     1.2. "ACTIVE ARQULE COMPOUND" shall mean any ArQule Compound or ArQule
Derivative Compound which exhibits confirmed significant functional activity
against a Target. The criteria for determining "significant functional activity"
for each Target is established by the Research Committee acting in accordance
with Section 2.

     1.3. "ACTIVE COMPOUND" shall mean any Active ArQule Compound or Active
Wyeth-Ayerst Compound.

     1.4. "ACTIVE WYETH-AYERST COMPOUND" shall mean any Wyeth-Ayerst Compound or
Wyeth-Ayerst Derivative Compound which exhibits confirmed significant functional
activity against a Target. The criteria for determining "significant functional
activity" for each Target is established by the Research Committee acting in
accordance with Section 2.

<PAGE>   7

     1.5. "AFFILIATE" shall mean a corporation or other legal entity that
controls, is controlled by, or is under common control with such party. For
purposes of this definition, "control" means the ownership, directly or
indirectly, of fifty percent (50%) or more of the outstanding equity securities
of a corporation which are entitled to vote in the election of directors or a
fifty percent (50%) or greater interest in the net assets or profits of an
entity which is not a corporation. For the purposes of this definition, Immunex
Corporation shall not be deemed a Wyeth-Ayerst Affiliate.

     1.6. "AGREEMENT" shall mean this Research and License Agreement, together
with EXHIBIT A and EXHIBIT B hereto.

     1.7. "ARQULE COMPOUND" shall mean any chemical that is synthesized by
ArQule using its proprietary technology and provided by ArQule to Wyeth-Ayerst
under the Mapping Array(TM) Program.

     1.8. "ARQULE DERIVATIVE COMPOUND" shall mean a Derivative Compound
synthesized by ArQule from an ArQule Compound under a Directed Array(TM) Program
described in Section 4.

     1.9. "ARQULE INTERNAL DEVELOPMENT PROGRAM" shall mean any testing or
screening activity fully funded and performed by ArQule itself with the primary
purpose of determining the functional activity in the Field of ArQule Compounds
or ArQule Derivative Compounds.

     1.10. "ARQULE PATENT RIGHTS" shall mean Patent Rights controlled or owned
by ArQule as of the Effective Date or during the term of this Agreement.

     1.11. "ARQULE TECHNOLOGY" shall mean all information and data which is
owned by ArQule or licensed by third parties to ArQule prior to or during the
Research Program and is necessary or useful to conduct the screening to discover
Active ArQule Compounds and Active Homologs thereto or to develop, make, use,
sell or seek regulatory approval in any country to market a product containing a
Licensed Compound; all to the extent and only to the extent that ArQule now has
or hereafter will have the right to grant licenses, immunities or other rights
thereunder.

     1.12. "ARRAY" shall mean a set of samples of structurally related chemical
compounds arranged in a format such as a microtiter screening plate.

     1.13. "CHEMICAL THEME" shall mean the chemical or structural
characteristics shared by a group of compounds as determined by the Research
Committee acting in accordance with Section 2.

     1.14. "CONFIDENTIAL INFORMATION" shall have the meaning set forth in
Section 9.1.

     1.15. "CONTRACT YEAR" shall mean each twelve (12) month calendar year of
the Research Period commencing on January 1 and ending on December 31 of each
such year. Notwithstanding the foregoing, the "Initial Contract Year" shall mean
the stub period beginning on the Effective Date and ending on December 31, 1997,
and, with respect to the

                                        2
<PAGE>   8

Directed Array(TM) Programs, the "Final Contract Year" shall mean the Contract
Year ending on December 31, 2000.

     1.16. "DERIVATIVE COMPOUND" shall mean a chemical compound structurally
derived in one or more steps from another by a process of modification or
partial substitution of at least one component wherein at least one structural
feature is retained at each process step. The number of intermediate steps or
compounds is not relevant to the classification of a compound as a Derivative
Compound. A compound need not have structural similarity to another compound in
order to be classified as a Derivative Compound.

     1.17. "DIRECTED ARRAY(TM)" shall mean an Array comprised of ArQule
Derivative Compounds or Wyeth-Ayerst Derivative Compounds, as the case may be,
synthesized by ArQule under a Directed Array(TM) Program described in Section 4.

     1.18. "DIRECTED ARRAY(TM) PROGRAM" shall mean a lead optimization program
based around a single Chemical Theme and conducted by ArQule as set forth in
Section 4.

     1.19. "DISCLOSING PARTY" shall mean that Party disclosing Confidential
Information to the other Party under Section 9.

     1.20. "EFFECTIVE DATE" shall mean the date first written above.

     1.21. "EXTRAORDINARY EXPENSES" shall mean those unusual expenses incurred
by ArQule required solely to further the Directed Array(TM) Program in
accordance with the Research Plan as approved by the Research Committee and
which are not contemplated by the Research Plan.

     1.22. "FDA" shall mean the United States Food and Drug Administration (or
its foreign equivalent in a Major Market Country).

     1.23. "FIELD" shall mean, with respect to a Target, all human therapeutic
and diagnostic pharmaceutical uses of a Licensed Compound.

     1.24. "IND-TRACK STATUS" shall mean the designation by the Wyeth-Ayerst
Discovery Council that a Licensed Compound meets the criteria set forth in
EXHIBIT B.

     1.25. "JOINT PATENT RIGHTS" shall mean any Patent Rights that are jointly
owned by the Parties, as set forth in Section 7.1(b).

     1.26. "LICENSED COMPOUND" shall mean any Active ArQule Compound or Active
Homologs thereto which the Research Committee has designated as such pursuant to
Section 3.2 or Section 4.3 hereof.

     1.27. "LICENSED COMPOUND SET" shall mean the set of Licensed Compounds
comprising at least one Active ArQule Compound and the Active Homologs thereto
which the Research Committee has designated as such pursuant to Section 3.2 or
Section 4.3 hereof. For the purposes of this Agreement, any reference made to a
Licensed Compound

                                        3
<PAGE>   9

applies to all compounds in the Licensed Compound Set to which the Licensed
Compound belongs.

     1.28. "MAJOR MARKET COUNTRY" shall mean the *****                  

     1.29. "MAPPING ARRAY(TM)" shall mean an Array of ArQule Compounds
synthesized by ArQule under the Mapping Array(TM) Program set forth in
Section 3.

     1.30. "MAPPING ARRAY(TM) PROGRAM" shall mean the Mapping Array(TM)
component of the Research Program as set forth in Section 3.

     1.31. "NET SALES" shall mean the aggregate Net Sales Price of
Royalty-Bearing Products in any Royalty Period.

     1.32. "NET SALES PRICE" shall mean with respect to a Royalty-Bearing
Product, the ****** invoiced by Wyeth-Ayerst, its Affiliates, Sublicensees
and/or Direct Licensees as appropriate, on sales or other dispositions of the
Royalty-Bearing Product to unrelated third parties, less the following items:

           *****

           *****                                                              
                                                                         
           *****
                                                                               
           *****
                                                                              
Such amounts shall be determined from the books and records of Wyeth-Ayerst, its
Affiliates and/or its Sublicensees, maintained in accordance with generally
accepted accounting principles, consistently applied.

     If a Royalty-Bearing Product is sold in bulk (as distinguished from
packaged pharmaceutical form) for resale in packaged or finished form, Net Sales
shall be calculated ***** . If a Royalty-Bearing Product is sold, or otherwise
commercially disposed of for value (including, without limitation, disposition
in connection with the delivery of other products or services), in a
transaction that is not an outright arm's length sale to an independent third
party, then the
        
        

* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                      4
<PAGE>   10

********** invoiced in such transaction shall be deemed to be the ***** that
would have been paid had there been such a sale at the *****  of such
Royalty-Bearing Product during the applicable royalty reporting period. Net
Sales Price shall not include any consideration received by Wyeth-Ayerst, its
Affiliates or its Sublicensees in respect of the sale, use or other disposition
of a Royalty-Bearing Product in a country as part of a clinical trial prior to
the receipt of all regulatory approvals required to commence full commercial
sales of such Royalty-Bearing Product in such country, except ***** pursuant to
which Wyeth-Ayerst, its Affiliates or Sublicensees is/are entitled, under
applicable regulatory policies, to recover costs incurred in providing such
products to the patients.    

     1.33. "PARTY" means ArQule or Wyeth-Ayerst or their respective Affiliates;
"PARTIES" means ArQule and Wyeth-Ayerst and their respective Affiliates.

     1.34. "PATENT RIGHTS" shall mean all Valid Claims of all issued patents and
reissues, reexaminations, extensions and supplementary protection certificates
thereof, and all patent applications and any divisions, continuations, or
continuations-in-part thereof or patents issuing thereon. For the purposes of
this Section, "Valid Claim" shall mean either (a) a claim of an issued patent
that has not been held unenforceable or invalid by an agency or a court of
competent jurisdiction in any unappealable or unappealed decision or (b) a claim
of a pending patent application that has not been abandoned or finally rejected
without the possibility of appeal or refiling and that has been pending for less
than ***** years from its priority date.

     1.35. "PHASE I CLINICAL TRIALS" shall mean clinical trials in a small
number of patients to determine the metabolism and pharmacologic actions of a
product in humans, the side effects associated with increasing doses and to
gather evidence on effectiveness and meeting the requirements established by the
FDA for Phase I clinical trials.

     1.36. "PHASE II CLINICAL TRIALS" shall mean clinical trials in a small
sample of the intended patient population to assess the efficacy for a specific
indication of a compound proposed to be used as a therapeutic or diagnostic
pharmaceutical product, to determine dose tolerance and the optimal dose range
as well as to gather additional information relating to safety and potential
adverse effects, and meeting the requirements established by the FDA for Phase
II clinical trials.

     1.37. "PHASE III CLINICAL TRIALS" shall mean clinical trials designed to
demonstrate safety and efficacy of a compound proposed to be used as a
therapeutic or diagnostic pharmaceutical product in an expanded patient
population at geographically dispersed study sites, meeting the requirements
established by the FDA for Phase III clinical trials.

     1.38. "PRECLINICAL COMPOUND" shall mean any Licensed Compound selected by
Wyeth-Ayerst or an Affiliate of Wyeth-Ayerst to enter into Preclinical
Development.

     1.39. "PRECLINICAL DEVELOPMENT" shall mean, with respect to any Preclinical
Compound, the commencement of IND-enabling toxicology studies.


* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                        5
<PAGE>   11



     1.40. "RECEIVING PARTY" shall mean that Party receiving Confidential
Information under Section 9.1.

     1.41. "RESEARCH PERIOD" shall mean the period during which the Research
Program, or any part thereof, remains in effect.

     1.42. "RESEARCH PLAN" shall mean a plan of research for each Directed
Array(TM) Program covering a minimum of a six-month period, which shall be
updated periodically as agreed to by the Parties pursuant to Section 2.2. The
initial Research Plan shall be developed by the Parties within thirty (30) days
of the Effective Date and be attached to this Agreement as EXHIBIT A.

     1.43. "RESEARCH PROGRAM" shall mean, collectively and individually, each of
the Directed Array(TM) Programs and the Mapping Array(TM) Program.

     1.44. "ROYALTY-BEARING PRODUCT" shall mean a product containing *****    

     1.45. "ROYALTY PERIOD" shall mean, with respect to each Royalty-Bearing
Product, every calendar quarter, or partial calendar quarter, commencing with
the first commercial sale of such Royalty-Bearing Product in any country and
ending on the later to occur of (i) the end of the quarter during which all
Patent Rights covering one or more active components per se of such
Royalty-Bearing Product expire in the applicable country, or (ii) ***** years
after such first commercial sale in the applicable country.

     1.46. "RESEARCH COMMITTEE" shall have the meaning set forth in Section 2.1.

     1.47. "SUBLICENSEE" shall mean any non-Affiliate third party licensed by
Wyeth- Ayerst to make, use (except where the right to use accompanies the sale
of any Royalty- Bearing Product by Wyeth-Ayerst or its Affiliates, Sublicensees
or Direct Licensees) or sell any Royalty-Bearing Product pursuant to any rights
granted hereunder.

     1.48. "TARGET" shall mean any biological target selected by Wyeth-Ayerst.

     1.49. "WYETH-AYERST COMPOUND" shall mean any chemical compound provided by
Wyeth-Ayerst or its Affiliates to ArQule under a Directed Array(TM) Program
described in Section 4.

     1.50. "WYETH-AYERST DERIVATIVE COMPOUND" shall mean a Derivative Compound
synthesized by ArQule from a Wyeth-Ayerst Compound under a Directed Array(TM)
Program described in Section 4.

     1.51. "WYETH-AYERST PATENT RIGHTS" shall mean Patent Rights controlled or
owned by Wyeth-Ayerst as of the Effective Date or during the Research Period.


* Confidential Treatment has been requested for the marked portions of this
  agreement.




                                       6
<PAGE>   12

     1.52. The above definitions are intended to encompass the defined terms in
both the singular and plural tenses.


2. MANAGEMENT OF RESEARCH PROGRAM.

     2.1. COMPOSITION OF RESEARCH COMMITTEE. The Parties hereby establish a
Research Committee comprised of six (6) members, with three (3) representatives
appointed by each Party. The members of the Research Committee shall be as
follows:

       ArQule Representatives                   Wyeth-Ayerst Representatives
       ----------------------                   ----------------------------

          *****                                   *****                    

          *****                                   *****                   

          *****                                   *****                         


A Party may change one or more of its representatives to the Research Committee
at any time upon notice to the other Party. Each Party will designate one of its
representatives as its team leader.

     2.2. DUTIES OF THE RESEARCH COMMITTEE. The Research Committee shall direct
and administer the Research Program. With respect to each Directed Array(TM)
Program, the Research Committee shall specifically determine the following: (i)
the appropriate number and type of Chemical Themes, to be submitted to the
Directed Array(TM) Program, subject to ArQule's right to exclude certain
compounds as set forth in Section 4.2 below; (ii) the appropriate number of
compounds that ArQule should generate in a Directed Array(TM) for a particular
Chemical Theme; and (iii) the appropriate amount of each compound in a Directed
Array(TM) that ArQule should deliver to Wyeth-Ayerst for further research and
development. The scope of each Chemical Theme will be determined on the basis of
the following criteria: (i) the specific reaction or reaction sequence used to
combine members of two or more discrete chemical units in which each chemical
unit bears the functional group(s) required for the specific reaction(s) that
result in the combination of the chemical units; and (ii) the extent to which a
class of compounds is related by a recurring structural motif associated with a
particular biological activity. In addition, the Research Committee shall (i)
determine the criteria of substantial structural homology and minimal functional
activity necessary to identify Active Homologs of an Active Compound, (ii)
determine the criteria of significant functional activity necessary to identify
an Active Compound, (iii) determine whether any Active ArQule Compound and any
Active Homolog thereto should be designated as a Licensed Compound and included
in a Licensed Compound Set pursuant to Section 3.2 or Section 4.3 hereof; (iv)
determine and update the list of Licensed Compounds; (v) revise and extend the
Research Plan periodically as agreed to by the Parties; (vi) allocate personnel
resources to be utilized by the parties under the Agreement; and (vii) resolve
all matters involving scientific questions.


* Confidential Treatment has been requested for the marked portions of this
  agreement.




                                        7
<PAGE>   13

     2.3. MEETINGS OF THE RESEARCH COMMITTEE. The Research Committee shall
conduct monthly telephone conferences and shall prepare and deliver a brief
written report describing the significant issues and discussions that take place
during such telephone conferences. A representative of the Research Committee
jointly appointed by its members shall provide each member with ***** *****
days notice of the time of any such telephone conferences and the proposed
agenda with respect thereto, unless waived by all members. The Research
Committee shall meet at least once each quarter alternately at the Parties'
locations, or at such other times and locations as the Research Committee
determines. A representative of the Research Committee jointly appointed by its
members shall provide each member with ***** days notice of the time
and location of meetings, unless such notice is waived by all members. If a
designated representative of a Party cannot attend a meeting of the Research
Committee, such Party may designate a different representative for that meeting
without notice to the other Party, and the substitute member will have full
power to vote on behalf of the permanent member. Except as otherwise provided
in this Section 2, all actions and decisions of the Research Committee will
require the unanimous consent of all of its members. If the Research Committee
fails to reach agreement upon any matter, the dispute will be resolved in
accordance with the procedures set forth in Section 13.4 below. Within *****
days following each quarterly meeting of the Research Committee, the Research
Committee shall prepare and deliver, to both Parties, a written report
describing the decisions made, conclusions and actions agreed upon.
        
     2.4. COOPERATION. Each Party agrees to provide the Research Committee with
information and documentation as reasonably required for the Research Committee
to fulfill its duties under this Agreement. In addition, each Party agrees to
make available its employees and consultants as reasonably requested by the
Research Committee. The Parties anticipate that members of the Research
Committee will communicate informally with each other and with employees and
consultants of the Parties on matters relating to the Directed Array(TM)
Program.

     2.5. VISITS TO FACILITIES. Members of the Research Committee shall have
reasonable access to the facilities of each Party where activities under this
Agreement are in progress, but only during normal business hours and with
reasonable prior notice. Each Party shall bear its own expenses in connection
with such site visits.


3. MAPPING ARRAY(TM) PROGRAM.

     3.1. CONDUCT OF MAPPING ARRAY(TM) PROGRAM. ArQule will supply Wyeth-Ayerst
with its Mapping Array(TM) Program containing approximately ***** each of  not
less than ***** different ArQule Compounds during the Initial Contract Year of
1997, ***** and approximately ***** different ArQule Compounds during the 
subsequent Contract Years for the term of the Mapping Array(TM) Program
provided for in Section 3.5. Each Mapping Array(TM) Program shall be based on 
approximately ***** Chemical Themes. *****, ArQule shall confirm that the 
ArQule Compounds within the Mapping Arrays(TM) are, on average, at least *****
pure.

* Confidential treatment has been requested for the marked portions of this
  agreement.

        
                                        8
<PAGE>   14

Promptly upon its receipt of any such Mapping Arrays(TM), Wyeth-Ayerst shall
commence testing of such Mapping Arrays(TM) for activity against Targets within
the Field. Upon the completion by Wyeth-Ayerst of its testing of any such
Mapping Arrays(TM), Wyeth-Ayerst shall promptly provide the ArQule team leader
with a telefax communication detailing the discovery of Active Compounds, which
telefax shall be followed by a confirmatory letter, PROVIDED, HOWEVER, that
Wyeth-Ayerst may withhold any Confidential Information it deems appropriate to
prevent disclosure of the Targets. At Wyeth-Ayerst's request, and subject to the
availability of such Active Compound(s) as Licensed Compound(s) in accordance
with the provisions of Section 3.2 hereof, ArQule shall resynthesize any Active
Compound(s) and will promptly supply Wyeth-Ayerst with an appropriate amount of
such Active Compound(s) for a second evaluation as determined by the Research
Committee.

     3.2. MUTUAL DISCLOSURE. Initially, ArQule will identify the Chemical Theme
of each Mapping Array(TM) but not the structures of the individual ArQule
Compounds in the Mapping Arrays(TM). Wyeth-Ayerst may screen the Mapping
Arrays(TM) against any Targets within the Field during the term of this
Agreement and thereafter. Initially, Wyeth-Ayerst will not disclose the Targets
screened. When Wyeth-Ayerst detects any Active ArQule Compound in a Mapping
Array(TM), ArQule will initially disclose whether such Active Compound or Active
Homolog thereto (i) is included within a Directed Array(TM) Program for a third
party for development in the Field, (ii) is being optimized by a third party
from a Mapping Array(TM) Program for development in the Field, (iii) is licensed
by a third party for development in the Field, or (iv) is included in an
existing ArQule Internal Discovery Program, in which case such Active ArQule
Compound and such Active Homologs thereto may not be reserved as per Section 3.3
or designated as Licensed Compounds. If such Active ArQule Compound and Active
Homologs may be reserved or designated as Licensed Compounds, ArQule will
disclose (a) the structure of each Active ArQule Compound and (b) the
structures, but not the locations in the Mapping Array(TM), of all Active
Homologs thereto, and Wyeth-Ayerst will disclose (a) the identity of the Target
and (b) the level of activity. All such disclosed information shall be treated
as Confidential Information by both Parties. The Parties agree that all Active
ArQule Compounds and Active Homologs thereto which exhibit significant
functional activity against Targets shall, subject to the approval of the
Research Committee, be submitted to the Directed Array(TM) Program under Section
4. Wyeth- Ayerst, at its discretion, may request that the Research Committee
designate any such Active ArQule Compound and Active Homologs thereto as
Licensed Compounds comprising a Licensed Compound Set if such Active ArQule
Compound and Active Homologs are still available as Licensed Compounds. Subject
to the foregoing, (a) ArQule shall notify the Research Committee that such
Active ArQule Compound and Active Homologs thereto are properly designated as
Licensed Compounds, and (b) provide Wyeth-Ayerst with the confirmed chemical
composition, structure, purity information and location of all Active ArQule
Compounds and Active Homologs thereto so designated as Licensed Compounds
belonging to such Licensed Compound Set.

     3.3. RESERVATION OF ACTIVE ARQULE COMPOUNDS. Prior to designating any
Active ArQule Compounds and Active Homologs thereto as Licensed Compounds
pursuant to Section 3.2 hereof, Wyeth-Ayerst, at its discretion, may notify
ArQule of its intent to license such Active ArQule Compounds and Active
Homologs, and request a reservation of such Active ArQule Compounds and Active
Homologs thereto (collectively the "Reserved

                                        9
<PAGE>   15

Compounds"). Upon ArQule receiving from Wyeth-Ayerst (i) a written request to
reserve such Reserved Compounds, and (ii) disclosure of the Target and activity
information pursuant to Section 3.2 hereof, ArQule shall reserve such Reserved
Compounds for subsequent designation by Wyeth-Ayerst as Licensed Compounds for a
period ending upon the earlier to occur of (i) *****, or (ii) ***** days.

     3.4. MAPPING ARRAY(TM) PROGRAM PAYMENTS. In consideration of the
performance by ArQule of the Mapping Array(TM) Program during the term provided
for in Section 3.5, Wyeth- Ayerst shall pay ArQule an annual subscription fee of
*****. Each subsequent annual subscription fee after the 1998 Contract Year
shall be as follows:

         1999 Contract Year Annual Subscription Fee = *****

         2000 Contract Year Annual Subscription Fee = *****

         2001 Contract Year Annual Subscription Fee = *****

Beginning in 1998, any such annual subscription fee is payable *****. The
payment schedule for annual subscription fees shall be as follows:

         In 1997 Contract Year:             ******

         In 1998 Contract Year:             ******

         In 1999 Contract Year:             ******

         In 2000 Contract Year:             ******

         In 2001 Contract Year:             ******

     3.5. TERM OF MAPPING ARRAY(TM) PROGRAM. The Mapping Array(TM) Program shall
commence on the Effective Date and continue until December 31, 2001, unless
earlier terminated as provided in Article 12 below. Wyeth-Ayerst may renew the
term of the Mapping Array(TM) Program at its option for additional periods of
***** on terms and conditions to be mutually agreed upon by the Parties.
Termination of the Mapping Array(TM) Program shall have no effect on the
continuation of any Directed Array(TM) Program.

     3.6. PERFORMANCE OF MAPPING ARRAY(TM) PROGRAM. During the term of the
Mapping Array(TM) Program, any Active ArQule Compound selected by Wyeth-Ayerst
from the Mapping Array(TM) Program for re-synthesis pursuant to this Agreement
shall be reproducible by ArQule in quantities of at least ***** or such other
reasonable quantity as determined by the Research Committee. The Parties agree
that the failure of ArQule to meet these performance criteria



* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       10
<PAGE>   16

of this section shall not constitute a material breach of the Agreement
sufficient for termination pursuant to Section 12.3 hereof. *****

4. DIRECTED ARRAY(TM) PROGRAM.

     4.1. DESCRIPTION OF DIRECTED ARRAY(TM) PROGRAMS. Subject to the approval of
the Research Committee and the provisions of Section 4.2, ArQule will
synthesize, under the direction of the Research Committee and in accordance with
the Research Plan, multiple Directed Arrays(TM) of compounds derived from (i)
each Wyeth-Ayerst Compound provided to ArQule by Wyeth-Ayerst for inclusion in a
Directed Array(TM) Program, and/or (ii) each Active ArQule Compound or Active
Homolog thereto provided by ArQule to Wyeth-Ayerst under the Mapping Array(TM)
Program for inclusion in a Directed Array(TM) Program. The Parties agree that,
during the period provided for in Section 4.5, ArQule will produce such Directed
Arrays(TM) in no less than ***** separate Directed Array(TM) Programs as
follows:

          (i) ***** Directed Array(TM) Programs during the Initial Contract
          Year of 1997,

          (ii) ***** Directed Array(TM) Programs during each of the Contract
          Years of 1998 and 1999, and

          (iii) ***** Directed Array(TM) Programs commenced during the Final
          Contract Year.

The Research Committee will determine which Active ArQule Compounds or Active
Homologs thereto, and which Wyeth-Ayerst Compounds are actually submitted to
the Directed Array(TM) Programs. Subject to Research Committee approval and
oversight, it is expected that each Directed Array(TM) Program should take
***** to complete, with an average of ***** for the Directed Array(TM) Programs
commenced in any Contract Year. In the event that such average exceeds ***** in
any Contract Year, the matter will be referred to the Research Committee to
develop a plan to accelerate the Directed Array(TM) Programs. Failure to
average ***** or less to complete the Directed Array(TM) Programs for any
Contract Year shall not be a material breach sufficient to terminate this
Agreement pursuant to Section 12.3. Each Directed Array(TM) program shall
result in the production of approximately ***** compounds per Chemical Theme
per Directed Array(TM) Program resulting in approximately  ***** compounds
generated for the ***** Directed Array(TM) Programs, PROVIDED, HOWEVER, that
the number of Chemical Themes actually submitted to the Directed Array(TM)
Program and the number of ArQule Derivative Compounds or Wyeth-Ayerst
Derivative Compounds actually produced per Chemical Theme will be determined by
the Research Committee. ArQule shall devote the resources necessary to produce
such Directed Array(TM) Program commensurate with the payments received by


* Confidential Treatment has been requested for the marked portions of this
  agreement.
 
        
                                       11
<PAGE>   17

ArQule for such Directed Array(TM) Program and ArQule agrees that the
determination of the actual numbers of compounds developed per Directed
Array(TM) Program shall be determined on a strict scientific basis to accomplish
the goals of such Directed Array(TM) Program rather than on the basis of
allocation of resources among ArQule's corporate collaborators. The Parties
intend that ArQule will produce approximately ***** of each such Derivative
Compound in the Directed Arrays(TM), and in the case of Wyeth-Ayerst Derivative
Compounds, subject to the availability of the original Wyeth-Ayerst Compounds;
PROVIDED, HOWEVER, that the amount of each Derivative Compound that ArQule
actually produces will ultimately be determined by the Research Committee.

     4.2. COMPOUNDS EXCLUDED FROM THE DIRECTED ARRAY(TM) PROGRAM. ArQule shall
have the right, at the time Wyeth-Ayerst seeks to include any (i) Active ArQule
Compound or Active Homolog thereto, or (ii) Wyeth-Ayerst Compound, in any
Directed Array(TM) Program, to exclude from such Directed Array(TM) Program any
such Active ArQule Compound, Active Homolog thereto, or Wyeth-Ayerst Compound
that is at that time (i) included within a Directed Array(TM) Program for a
third party for development in the Field, (ii) being optimized by a third party
from a Mapping Array(TM) Program for development in the Field, (iii) previously
licensed by a third party for development in the Field, or (iv) is included in
an existing ArQule Internal Discovery Program. In the event that ArQule excludes
a compound from a Directed Array(TM) Program pursuant to Subsection (iv) of this
Section, and to the extent ArQule may be permitted to do so in respect of
agreements with third parties, ***** .

     4.3. CONDUCT OF DIRECTED ARRAY(TM) PROGRAM. Each Directed Array(TM) Program
shall be conducted in a good scientific manner and in compliance with all
applicable legal requirements. The conduct of the Directed Array(TM) Program
shall be the primary responsibility of ArQule with participation by
Wyeth-Ayerst. Directed Arrays(TM) may be produced by ArQule in one or more
iterations as directed by the Research Committee. Wyeth-Ayerst shall propose
Chemical Themes to the Research Committee for inclusion in a Directed Array(TM)
Program. If the Research Committee approves the inclusion of the proposed
Chemical Theme, Wyeth-Ayerst shall provide ArQule with the requisite amount and
purity of Wyeth-Ayerst Compounds for that Chemical Theme, as directed by the
Research Committee. ArQule shall thereupon diligently synthesize Directed
Arrays(TM) of ArQule Derivative Compounds or Wyeth-Ayerst Derivative Compounds,
as the case may be, in accordance with the Research Plan. Wyeth-Ayerst shall, in
its discretion, be responsible for conducting screening for binding affinity
and/or functional activity of all compounds in the Directed Arrays(TM). The
Parties shall continue the procedure described in this Section 4.3 for each
Active Compound until the earliest to occur of (i) the determination by the
Research Committee, in accordance with Section 2.2, to designate any such Active
ArQule Compound and any Active Homolog thereto as Licensed Compounds belonging
to a Licensed Compound

* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                      12
<PAGE>   18

Set, (ii) the determination by the Research Committee to cease further testing
of such Active Compound, (iii) the termination of such Directed Array(TM)
Program pursuant to Section 4.5, or (iv) termination of this Agreement in
accordance with Section 12. In the event that the Research Committee cannot
agree on a determination to be made by the Research Committee hereunder, then
such determination shall be resolved pursuant to Section 13.4. Notwithstanding
the foregoing, all Active ArQule Compounds and Active Homologs thereto arising
from the Directed Array(TM) Program and designated as Licensed Compounds, shall
remain exclusive to Wyeth-Ayerst, and ArQule or any of its licensees or its
pharmaceutical partners shall have no rights thereto except as otherwise
provided for in this Agreement.

     4.4. DIRECTED ARRAY(TM) PROGRAM PAYMENTS.

          4.4.1. DELIVERY FEE. In consideration of the performance by ArQule of
the Directed Array(TM) Program, Wyeth-Ayerst shall pay ArQule a delivery fee
equal to ***** for each Directed Array(TM) Program commenced during the 1997
and 1998 Contract Years. Wyeth-Ayerst shall make the following delivery fee
payment to ArQule for the Directed Array(TM) Programs commenced during  
subsequent Contract Years:
        
         1999 Contract Year Delivery Fee =*****

         2000 Contract Year Delivery Fee = *****

All such delivery fees are payable *****. The annual payment schedule for such 
fees is expected to be as follows: 

<TABLE> 
<CAPTION>

    <S>                            <C>
    In 1997 Contract Year:        ***** / commence * Directed Array(TM)Programs.

    In 1998 Contract Year:        ***** / commence * and complete * Directed
                                  Array(TM) Programs.

    In 1999 Contract Year:        ***** / commence and complete * Directed Array(TM)
                                  Programs.

    In 2000 Contract Year:        ***** / commence and complete * Directed Array(TM)
                                  Programs.
</TABLE>

The parties agree that due to the uncertain scientific nature of any Directed
Array(TM) Program, the completion of the expected number of Directed Array(TM)
Programs in any one year may not occur in the same year that they are initiated,
and in such case, Wyeth-Ayerst will not be obligated to make the payments
scheduled in that year, but only to make the remaining payments when the
Directed Array(TM) Programs are actually completed.

          4.4.2. EXPENSES. In addition to the amounts payable pursuant to
Section 4.4.1 above, Wyeth-Ayerst shall pay any and all Extraordinary Expenses
of ArQule, as required and approved by the Research Committee which shall
approve such Extraordinary Expenses before they are incurred.


* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                      13

<PAGE>   19

     4.5. TERM OF DIRECTED ARRAY(TM) PROGRAMS. The term of each Directed
Array(TM) Program shall begin upon the commencement of such Directed Array(TM)
Program and, unless earlier terminated as provided in Article 12 below,
terminate on the first anniversary of such commencement date unless extended by
the Research Committee because of extraordinary circumstances. The period for
completing all Directed Array(TM) Programs commenced pursuant to Section 4.1
hereof shall terminate at the end of the Final Contract Year, PROVIDED, HOWEVER,
that such period may be extended for additional periods of ***** years at
***** on terms and conditions to be mutually agreed upon by the Parties.

     4.6. PERFORMANCE OF DIRECTED ARRAY(TM) PROGRAM. During the term of the
Directed Array(TM) Program, any ArQule Derivative Compound and any Wyeth-Ayerst
Derivative Compound selected for resynthesis pursuant to this Agreement shall be
reproducible by ArQule in quantities of at least ***** or such other reasonable
quantity as determined by the Research Committee. In the event that ArQule is
unable to reproduce such compound in accordance with the performance criteria
set forth in this section, the Parties agree to submit the matter to the
Research Committee for development of a plan to achieve such performance
criteria and to ultimately resolve the matter in accordance with this Agreement.
The Parties agree that the failure of ArQule to meet the performance criteria of
this section shall not constitute a material breach of the Agreement sufficient
for termination pursuant to Section 12.3 hereof.


5. LICENSE GRANTS; REVERSION OF RIGHTS.

     5.1. SCREENING LICENSES. ArQule hereby grants to Wyeth-Ayerst, under ArQule
Patent Rights and ArQule Technology (a) a nonexclusive, royalty-free license
***** to test each Mapping Array(TM) for significant functional activity
against Targets; and (b) an exclusive, royalty-free license to test each
Directed Array(TM) for significant functional activity against Targets.
        
     5.2. COMMERCIALIZATION LICENSE. Upon the designation of Wyeth-Ayerst and
upon the designation by the Research Committee of any Active ArQule Compound or
any Active Homolog thereto as a Licensed Compound, ArQule shall grant to
Wyeth-Ayerst, under any intellectual property rights owned solely by ArQule or
jointly with Wyeth-Ayerst or controlled by ArQule, including ArQule Patent
Rights, Joint Patent Rights and ArQule Technology, covering the composition,
manufacture or use of any such Licensed Compound selected by Wyeth-Ayerst for
Preclinical Development, an exclusive, worldwide royalty-bearing license 
***** subject to Section 5.3 (i) to develop or have developed Royalty-Bearing
Products incorporating Licensed Compounds for use in the Field (ii) to make or
have made Royalty- Bearing Products incorporating Licensed Compounds for use,
distribution and sale in the Field, and (iii) to distribute for sale and sell
in the Field    Royalty-Bearing Products incorporating Licensed Compounds,
PROVIDED, HOWEVER, *****.

* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                      14
<PAGE>   20

     5.3. REVERSION OF RIGHTS; RETURN OF MATERIALS. With respect to an Active
ArQule Compound and Active Homologs thereof composing a Licensed Compound Set
identified by Wyeth-Ayerst from a Mapping Array(TM) Program, in the event that
***** In such event, ArQule shall thereafter be free to
offer such Active ArQule Compounds and Active Homologs thereto belonging to such
Licensed Compound Set to third parties pursuant to a Mapping Array Program,
including the right to grant licenses covering such reverted Active ArQule
Compounds and Active Homologs to third parties for development and
commercialization resulting from independent discoveries arising from such
Mapping Array(TM) Program. Upon termination of such license by ArQule,
Wyeth-Ayerst shall (i) grant to ArQule an exclusive license, with the right to
grant sublicenses, to manufacture, use or sell such Active ArQule Compounds and
Active Homologs thereto under any Joint Patent Rights covering the composition
or use of such Active ArQule Compounds and Active Homologs and (ii) return to
ArQule all Proprietary Materials and Confidential Information supplied by ArQule
which relate to such Active ArQule Compounds and Active Homologs. ArQule agrees
not to disclose any Wyeth-Ayerst Confidential Information to any third party
regarding such reverted Active ArQule Compounds and Active Homologs in
accordance with Article 9 hereof. ***** . Notwithstanding the foregoing, 
pursuant to Section 4.3 hereof, all Active ArQule Compounds and Active Homologs
thereto arising from the Directed Array(TM) Program and designated as Licensed
Compounds, shall remain exclusive to Wyeth-Ayerst, and ArQule or any of its
licensees or its pharmaceutical partners shall have no rights thereto except as
otherwise provided for in this Agreement.
        
        5.4. DIRECT LICENSES TO AFFILIATES. Wyeth-Ayerst may, at any time,
request from ArQule, and ArQule agrees to grant directly to Wyeth-Ayerst
Affiliates in any country other than the United States equivalent rights as
granted to Wyeth-Ayerst on equivalent terms and conditions as agreed to by
Wyeth-Ayerst under this Agreement. Accordingly, upon receipt of Wyeth-Ayerst's
request, ArQule shall enter into and sign a direct license agreement or
agreements with such Wyeth-Ayerst Affiliates designated by Wyeth-Ayerst in the
request. All direct license agreements coming into force under this section
shall contain terms and conditions which are equivalent with those in this
Agreement, subject only to such modifications, as may be required by the laws
or regulations of the country to be demonstrated by Wyeth-Ayerst in which such
direct license may still be exercised, but only to the extent such
modifications are outside Wyeth-Ayerst's or its Affiliates' direct or indirect

* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                       15
<PAGE>   21

control, including, but not limited to, restrictions against the remittance of
royalties and limitations upon the term or duration of said direct license
agreement. In those countries in which the validity of such a direct license
agreement requires prior government approval or registration, such direct
license agreement shall not be binding or have force or effect until the
required governmental approval or registration has been granted.


6. OWNERSHIP OF COMPOUNDS.

     6.1. WYETH-AYERST COMPOUNDS; WYETH-AYERST DERIVATIVE COMPOUNDS. All Wyeth-
Ayerst Compounds and Wyeth-Ayerst Derivative Compounds shall be owned by Wyeth-
Ayerst or its Affiliates, except, and only to the extent that any such compound
(i) was under development by ArQule (including programs with academic
collaborators or corporate partners) before such compound was proposed to be
included in the Directed Array(TM) Program; (ii) was independently developed by
ArQule employees who had no access to Wyeth-Ayerst Confidential Information
regarding the particular compound as evidenced by sufficient written
documentation, or (iii) was already within a screening array before such
compound was proposed to be included in the Directed Array(TM) Program.

     6.2. ARQULE COMPOUNDS; ARQULE DERIVATIVE COMPOUNDS. All ArQule Compounds
and ArQule Derivative Compounds shall be owned by ArQule except, and only to the
extent that, any such compound (i) was under development by Wyeth-Ayerst before
such compound was proposed to be included in the Directed Array(TM) Program;
(ii) was independently developed by Wyeth-Ayerst employees who had no access to
ArQule Confidential Information regarding the particular compound as evidenced
by sufficient written documentation, or (iii) was already in the possession of
Wyeth-Ayerst before it was provided by ArQule to Wyeth-Ayerst or its Affiliates.


7. INTELLECTUAL PROPERTY RIGHTS.

     7.1. OWNERSHIP OF PATENT RIGHTS.

          (a) ARQULE PATENT RIGHTS. Any Patent Rights covering Active ArQule
     Compounds only will be owned solely by ArQule except as provided in Section
     7.1(b).

          (b) JOINT PATENT RIGHTS. Any Patent Rights filed by either Party (i)
     covering both Active ArQule Compounds and Active Wyeth-Ayerst Compounds,
     (ii) claiming an Active ArQule Compound and uses thereof discovered by
     Wyeth-Ayerst; and/or (iii) claiming an Active Wyeth-Ayerst Compound and
     uses thereof discovered by ArQule, shall be owned jointly by ArQule and
     Wyeth-Ayerst.

          (c) WYETH-AYERST PATENT RIGHTS. Any Patent Rights covering Active
     Wyeth-Ayerst Compounds only will be owned solely by Wyeth-Ayerst except as
     provided in Section 7.1(b).


                                       16
<PAGE>   22

          (d) PATENT RIGHTS GENERALLY. Any Patent Rights arising out of or
     related to this Agreement, the ownership of which cannot be determined from
     Subsections (a), (b) or (c) of this Section 7.1, will be owned by the
     Party(ies) having inventorship under the patent laws of the United States.

     7.2. MANAGEMENT OF JOINT PATENT RIGHTS. The Parties shall agree upon a
mutually acceptable independent patent attorney who will be responsible, at
Wyeth-Ayerst's expense, for the preparation, filing, prosecution, and
maintenance of any Joint Patent Rights claiming such inventions. In the event of
any disagreement concerning any Joint Patent Rights, the matter shall be
resolved in accordance with Section 13.4. Wyeth-Ayerst shall consult with ArQule
as to the preparation, filing, prosecution, and maintenance of such Joint Patent
Rights reasonably prior to any deadline or action with the U.S. Patent &
Trademark Office or its foreign equivalent in a Major Market Country, and shall
furnish to ArQule copies of all relevant documents reasonably in advance of such
consultation. In the event that Wyeth- Ayerst desires to abandon such Joint
Patent Rights or later declines responsibility for such Joint Patent Rights,
Wyeth-Ayerst shall provide reasonable prior written notice to ArQule of such
intention to abandon or decline responsibility, and ArQule shall have the right,
at its expense, to prepare, file, prosecute, and maintain such Joint Patent
Rights.

     7.3. COOPERATION OF THE PARTIES. Each Party agrees to cooperate fully in
the preparation, filing, and prosecution of any Patent Rights under this
Agreement. Such cooperation includes, but is not limited to:

                    (a) executing all papers and instruments, or requiring its
          employees or agents, to execute such papers and instruments, so as to
          effectuate the ownership of Patent Rights set forth in Section 7.1
          above and to enable the other Party to apply for and to prosecute
          patent applications in any country;

                    (b) promptly informing the other Party of any matters coming
          to such Party's attention that may affect the preparation, filing, or
          prosecution of any such patent applications; and

                    (c) undertaking no actions that are potentially deleterious
          to the preparation, filing, or prosecution of such patent
          applications.

     7.4. INFRINGEMENT BY THIRD PARTIES. ArQule and Wyeth-Ayerst shall each
promptly notify the other in writing of any alleged or threatened infringement
by a third party of any ArQule Patent Right, Wyeth-Ayerst Patent Right or Joint
Patent Right of which they become aware. ArQule may elect, but is under no
obligation, to initiate legal action with respect to an ArQule Patent Right
against such third party in its sole discretion, and Wyeth-Ayerst shall
cooperate fully with ArQule in any such action at its own out-of-pocket
expenses, further provided that Wyeth-Ayerst shall have the right to join as a
party. Wyeth-Ayerst shall have the right to be represented by legal counsel of
its own choosing at its sole expense. If ArQule, within ***** months of receipt
of such notice or such lesser period of time if a further delay would result
in material harm, or the loss of a material right, has not commenced legal
action against an infringer whose infringing product has a market share larger
than ***** of the sales of a product competing with a Royalty-Bearing


* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                       17
<PAGE>   23

Product and embraced by a Valid Claim of such ArQule Patent Rights licensed to
Wyeth-Ayerst hereunder, upon written notice from Wyeth-Ayerst, ArQule, in its
sole discretion, shall either (i) initiate such action, or (ii) authorize
Wyeth-Ayerst to commence such action. Wyeth-Ayerst may elect, but is under no
obligation, to initiate legal action with respect to a Wyeth-Ayerst Patent
Rights or Joint Patent Rights against such third party in its sole discretion,
and ArQule shall cooperate fully with Wyeth-Ayerst in any such action at its own
out-of-pocket expenses, further provided that ArQule shall have the right to
join as a party. ArQule shall have the right to be represented by legal counsel
of its own choosing at its sole expense. If Wyeth-Ayerst, within ***** months
of receipt of such notice or such lesser period of time if a further delay would
result in material harm, or the loss of a material right, has not commenced
legal action against an infringer whose infringing product has a market share
larger than ***** of the sales of a product competing with a Royalty-Bearing
Product and embraced by a Valid Claim in that country of such Wyeth-Ayerst
Patent Rights or Joint Patent Rights, upon written notice from ArQule,
Wyeth-Ayerst, in its sole discretion, shall either (i) initiate such action, or
(ii) authorize ArQule to commence such action. Notwithstanding anything to the
contrary, any settlement of such legal action by the initiating Party shall
require the consent of the non-initiating Party, which consent shall not be
unreasonably withheld. The Party whose Patent Rights allegedly are being
infringed, if they initiate such action, shall not be required to bring or
maintain more than one such suit at any time with respect to claims directed to
any one method of manufacture or composition of matter. All monies recovered
upon the final judgment or settlement of any such suit shall be shared, after
reimbursement of expenses, by ArQule and Wyeth-Ayerst pro rata according to the
respective percentages of costs borne by each Party in the suit pursuant to the
Section 7.4. Notwithstanding the foregoing, ArQule and Wyeth-Ayerst shall fully
cooperate with each other in the planning and execution of any action to
enforce the Patent Rights, and shall join suit if required by law to do so in
order to bring such action.
        
     7.5. INFRINGEMENT OF THIRD PARTY RIGHTS.

               (a) If Wyeth-Ayerst should be of the reasonable opinion that it
cannot make, import, use, market and/or sell a Royalty-Bearing Product without
infringing a third party's patent, and where such infringement arises solely and
directly from the use or sale of an ArQule Compound or ArQule Derivative
Compound (but not a Wyeth-Ayerst Derivative Compound), it shall notify ArQule.
Both Parties then shall seek an opinion of patent counsel acceptable to both
Parties and shall share the costs thereof. If such patent counsel concurs with
Wyeth-Ayerst's opinion, the Parties shall jointly or independently endeavor to
secure a license from the third party on terms that are acceptable to both
Parties.

               (b) If, in the opinion of patent counsel selected under
Subsection (a) hereof, the third party patent, if litigated, would be found to
be invalid or not infringed by the manufacture or sale of Royalty-Bearing
Products, or if the Parties otherwise mutually agree to obtain a license to such
third party patent, the Parties shall proceed in accordance with the terms of
this Agreement, unless an action for infringement is brought against one or both
Parties.

               (c) If either Party is sued for patent infringement of any third
party patents arising out of the manufacture, use, sale or importation of
Royalty-Bearing Products, and


* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       18
<PAGE>   24

where such infringement arises solely and directly from the use or sale of an
ArQule Compound or ArQule Derivative Compound (but not a Wyeth-Ayerst Derivative
Compound), the Parties shall promptly meet to discuss the course of action to be
taken to resolve or defend any such infringement litigation. In such event,
Wyeth-Ayerst shall determine the course of action with regard to such
infringement litigation in its sole discretion, and ArQule shall provide
Wyeth-Ayerst with such assistance as is reasonably necessary and shall cooperate
in the defense of any such action.

               (d) Subject to Section 8.9, Wyeth-Ayerst shall bear all the costs
and expenses arising in connection with any of the activities described in
Sections 7.5(b) and 7.5(c).

     7.6. TRADEMARKS. Royalty-Bearing Products shall be marketed and sold under
the trademark of Wyeth-Ayerst. Upon the termination of this Agreement,
Wyeth-Ayerst shall continue to use its trademarks with respect to
Royalty-Bearing Products.


8. PAYMENTS, REPORTS, AND RECORDS.

     8.1. ACCESS FEE. In partial consideration for Wyeth-Ayerst obtaining access
to ArQule's Mapping Array(TM) Program and Directed Array(TM) Program as provided
herein, Wyeth-Ayerst shall pay to ArQule a technology access fee equal to
***** (the "Access Fee") payable ***** , and for which Wyeth-Ayerst shall
receive from ArQule a number of shares of ArQule Common Stock, determined in
accordance with and subject to the terms and conditions of a certain Common
Stock Purchase Agreement entered into by the Parties of even date hereof.
        
     8.2. RESEARCH AND DEVELOPMENT PAYMENTS. In partial consideration of the
rights granted Wyeth-Ayerst under this Agreement, Wyeth-Ayerst shall pay ArQule
the following amounts within ***** days after each occurrence of the following
milestones:


Payment for Royalty-
Bearing Products                             Events
- ----------------                             ------

   *****                                     *****
        

   *****                                     *****


   *****                                     *****


   *****                                     *****



* Confidential Treatment has been requested for the marked portions of this
  agreement.



                                       19
<PAGE>   25

         *****                     *****
              
              

         *****                     *****
              
              
              

         *****                     *****
              
              
              

         *****                     *****
              
              
As used in this Section 8.2, ***** .              



Such Research and Development payments shall be non-refundable and shall not be
credited against royalties payable to ArQule under this Agreement. Research and
Development payments shall be paid for the first occurrence of each Event listed
above with respect to each Royalty-Bearing Product. Wyeth-Ayerst shall promptly
notify ArQule of each occurrence of any of the foregoing Events.

     8.3. MARGINAL ROYALTIES. In consideration of the licenses granted to
Wyeth-Ayerst hereunder, for each Royalty Period, Wyeth-Ayerst shall pay to
ArQule a royalty for each Royalty-Bearing Product of:

        Annual Net Sales                        Marginal Royalty Rate
        ----------------                       (Percentage Of Net Sales)
                                               -------------------------

      *****                                            *****

      *****                                            *****



* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       20
<PAGE>   26



     8.4. REPORTS AND PAYMENTS. Within ***** days after the conclusion of each
Royalty Period, Wyeth-Ayerst shall deliver to ArQule a report containing the
following information:

                    (a) A report of the gross sales of Royalty-Bearing Products
          by Wyeth-Ayerst, its Affiliates, Sublicensees and Direct Licensees
          during the applicable Royalty Period in each country of sale in
          sufficient detail to permit confirmation of the accuracy of the
          royalty payment made;

                    (b) adjustments and calculation of Net Sales for the
          applicable Royalty Period in each country of sale; and

                    (c) total Net Sales in U.S. dollars, together with the
          exchange rates used for conversion.

All such reports shall be maintained in confidence by ArQule. If no royalties
are due to ArQule for any reporting period, the report shall so state.
Concurrent with this report, Wyeth-Ayerst shall remit to ArQule any payment due
for the applicable Royalty Period. The method of payment shall be mutually
agreed to. All amounts payable to ArQule under this Section will first be
calculated in the currency of sale and then converted into U.S. dollars in
accordance with Section 8.5, and such amounts shall be paid without deduction of
any withholding taxes, value-added taxes, or other charges applicable to such
payments.

     8.5. INVOICES; PAYMENTS IN U.S. DOLLARS. With the exception of Access Fee,
Research and Development and royalty payments due under Sections 8.1, 8.2 and
8.3, respectively, ArQule shall submit invoices to Wyeth-Ayerst for each payment
due ArQule hereunder (including without limitation all payments due pursuant to
Section 3.4), and Wyeth-Ayerst shall pay such invoices within ***** days of
receipt thereof. All payments due under this Agreement shall, except as provided
in Section 8.6 below, be payable in United States dollars. Conversion of foreign
currency to U.S. dollars shall be made at the conversion rate existing in the
United States (as reported in the WALL STREET JOURNAL) on the last working day
of the calendar quarter preceding the applicable calendar quarter. Such payments
shall be without deduction of exchange, collection, or other charges.

     8.6. PAYMENTS IN OTHER CURRENCIES. If by law, regulation, or fiscal policy
of a particular country, conversion into United States dollars or transfer of
funds of a convertible currency to the United States is restricted or forbidden,
Wyeth-Ayerst shall give ArQule prompt written notice of such restriction, which
notice shall satisfy the ***** day payment deadline described in Section 8.5.
Wyeth-Ayerst shall pay any amounts due ArQule through whatever lawful methods
ArQule reasonably designates; provided, however, that if ArQule fails to
designate such payment method within ***** days after ArQule is notified of the
restriction, then Wyeth-Ayerst may deposit such payment in local currency to 
the credit of ArQule in a recognized banking institution selected by
Wyeth-Ayerst and identified by written notice to ArQule, and such deposit shall
fulfill all obligations of Wyeth-Ayerst to ArQule with respect to such payment.


* Confidential Treatment has been requested for the marked portions of this
  agreement. 

                                       21
<PAGE>   27

     8.7. RECORDS. Wyeth-Ayerst and its Affiliates shall maintain complete and
accurate records of Royalty-Bearing Products made, used or sold by them or their
Sublicensees or Direct Licensees under this Agreement, and any amounts payable
to ArQule in relation to such Royalty-Bearing Products, which records shall
contain sufficient information to permit ArQule to confirm the accuracy of any
reports delivered to ArQule in accordance with Section 8.4. Wyeth-Ayerst shall
retain such records relating to a given Royalty Period for at least ***** years
after the conclusion of that Royalty Period. ArQule shall have the right, at
its own expense, to cause an independent certified public accountant reasonably
acceptable to Wyeth-Ayerst at a date and time mutually agreed upon by both
Parties and after giving Wyeth-Ayerst at least ***** days written notice to
inspect such records during normal business hours for the sole purpose of
verifying any reports and payments delivered under this Agreement. Such
accountant shall not disclose to ArQule any information other than information
relating to accuracy of reports and payments delivered under this Agreement and
shall provide the Wyeth-Ayerst with a copy of any report given to ArQule. The
Parties shall reconcile any underpayment or overpayment within ***** days after
the accountant delivers the results of the audit. In the event that any audit
performed under this Section reveals an underpayment in excess of ***** in any
Royalty Period, Wyeth-Ayerst shall bear the full cost of such audit. ArQule may
exercise its rights under this Section only once every  year and only with
reasonable prior notice to the other Party.

        8.8. TERM OF ROYALTY OBLIGATION. Wyeth-Ayerst shall be obligated to pay
royalties on each Royalty-Bearing Product on a country-by-country basis for the
Royalty Period. Thereafter, Wyeth-Ayerst shall have a fully paid up license
from ArQule with respect to such Royalty-Bearing Product.

     8.9. THIRD PARTY ROYALTIES. If Wyeth-Ayerst is required to pay royalties to
a non-Affiliate third party in order to make, use or sell a Royalty-Bearing
Product for which Wyeth-Ayerst is then paying royalties to ArQule, to avoid
infringing such third party's patent rights, or where such royalties are payable
to such third party as a result of adjudication of an infringement action or
settlement thereof, and where such infringement arises solely and directly from
the use or sale of an ArQule Compound or ArQule Derivative Compound (but not a
Wyeth-Ayerst Derivative Compound), Wyeth-Ayerst may deduct up to ***** of such
third party royalty payments from royalties thereafter payable to ArQule;
PROVIDED, HOWEVER, that *****
        

9. CONFIDENTIAL INFORMATION.

     9.1. DEFINITION OF CONFIDENTIAL INFORMATION. Confidential Information shall
mean any technical or business information furnished by the Disclosing Party to
the Receiving


* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       22
<PAGE>   28



Party in connection with this Agreement and specifically designated as
confidential. Such Confidential Information may include, without limitation, the
identity of a chemical compound, the use of a chemical compound, trade secrets,
know-how, inventions, technical data or specifications, testing methods,
business or financial information, research and development activities, product
and marketing plans, and customer and supplier information.

     9.2. DESIGNATION OF CONFIDENTIAL INFORMATION. Confidential Information that
is disclosed in writing shall be marked with a legend indicating its
confidential status. Confidential Information that is disclosed orally or
visually shall be documented in a written notice prepared by the Disclosing
Party and delivered to the Receiving Party within thirty (30) days of the date
of disclosure; such notice shall summarize the Confidential Information
disclosed to the Receiving Party and reference the time and place of disclosure.

     9.3. OBLIGATIONS. The Receiving Party agrees that it shall:

                    (a) maintain all Confidential Information in strict
          confidence, except that the Receiving Party may disclose or permit the
          disclosure of any Confidential Information to its, and its Affiliates,
          directors, officers, employees, consultants, and advisors who are
          obligated to maintain the confidential nature of such Confidential
          Information and who need to know such Confidential Information for the
          purposes set forth in this Agreement;

                    (b) use all Confidential Information solely for the purposes
          set forth in, or as permitted by, this Agreement; and

                    (c) allow its directors, officers, employees, consultants,
          and advisors to reproduce the Confidential Information only to the
          extent necessary to effect the purposes set forth in this Agreement,
          with all such reproductions being considered Confidential Information.

     9.4. EXCEPTIONS. The obligations of the Receiving Party under Section 9.3
above shall not apply to the extent that the Receiving Party can demonstrate
that certain Confidential Information:

                    (a) was in the public domain prior to the time of its
          disclosure under this Agreement;

                    (b) entered the public domain after the time of its
          disclosure under this Agreement through means other than an
          unauthorized disclosure resulting from an act or omission by the
          Receiving Party;

                    (c) was independently developed or discovered by the
          Receiving Party without use of the Confidential Information;

                    (d) is or was disclosed to the Receiving Party at any time,
          whether prior to or after the time of its disclosure under this
          Agreement, by a third party having no fiduciary relationship with the
          Disclosing Party and having no obligation of

                                       23
<PAGE>   29

          confidentiality to the Disclosing Party with respect to such
          Confidential Information; or

                    (e) is required to be disclosed to comply with applicable
          laws or regulations (such as disclosure to the FDA or the United
          States Patent and Trademark Office or to their foreign equivalents),
          or to comply with a court or administrative order, provided that the
          Disclosing Party receives prior written notice of such disclosure and
          that the Receiving Party takes all reasonable and lawful actions to
          obtain confidential treatment for such disclosure and, if possible, to
          minimize the extent of such disclosure.

     9.5. RETURN OF CONFIDENTIAL INFORMATION. Upon the termination of this
Agreement, at the request of the Disclosing Party, the Receiving Party shall
destroy or return to the Disclosing Party all originals, copies, and summaries
of documents, materials, and other tangible manifestations of Confidential
Information in the possession or control of the Receiving Party, except that the
Receiving Party may retain one copy of the Confidential Information in the
possession of its legal counsel (for ArQule) and its Legal Department (for
Wyeth-Ayerst) solely for the purpose of monitoring its obligations under this
Agreement.

     9.6. PUBLICATIONS. ArQule shall not publish any scientific publications
with respect to Active ArQule Compounds, Active Homologs, ArQule Derivative
Compounds, Wyeth- Ayerst Compounds or Wyeth-Ayerst Derivative Compounds without
the prior written permission of Wyeth-Ayerst, which may be withheld in its sole
discretion.

     9.7. SURVIVAL OF OBLIGATIONS. The obligations set forth in this Article
shall remain in effect for a period of ***** years after termination of this
Agreement, except that the obligations of the Receiving Party to destroy or
return Confidential Information to the Disclosing Party shall survive until
fulfilled.


10. REPRESENTATIONS AND WARRANTIES.

     10.1. AUTHORIZATION. Each Party represents and warrants to the other that
it has the legal right and power to enter into this Agreement, to extend the
rights and licenses granted to the other in this Agreement, and to fully perform
its obligations hereunder, and that the performance of such obligations will not
conflict with its charter documents or any agreements, contracts, or other
arrangements to which it is a Party.

     10.2. INTELLECTUAL PROPERTY. Each Party further represents that it (a) owns
or is the licensee in good standing of all Patent Rights, trade secrets and
other intellectual property to be used by it in connection with the Research
Program, except to the extent that such use is to be based upon patents,
trademarks and other intellectual property furnished by the other Party; (b) has
received no notice of infringement or misappropriation of any alleged rights
asserted by any third party in relation to any technology to be used by it in
connection with the Research Program; (c) is not in default with respect to any
license agreement related to the Research Program; and (d) its directors,
officers and employees responsible for intellectual property matters are not
aware of any patent, trade secret or other right of any


* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       24
<PAGE>   30

third party which could materially adversely affect its ability to carry out its
responsibilities under the Research Program or the other Party's ability to
exercise or exploit any license granted to it under this Agreement. Such Party
agrees to immediately notify the other Party in writing in the event such Party
hereafter receives a notice of the type referred to in (b) above, becomes in
default under any license agreement referred to in (c) above, or becomes aware
of any patent, trade secret or other right of the nature referred to in (d)
above.


11. INDEMNIFICATION AND INSURANCE.

     11.1. WYETH-AYERST INDEMNITY OBLIGATIONS. Wyeth-Ayerst (the "Indemnitor")
agrees to defend, indemnify and hold ArQule, its Affiliates and their respective
directors, officers, employees and agents (the "Indemnitee") harmless from all
costs, judgments, liabilities and damages assessed by a court of competent
jurisdiction arising from claims asserted by a third party against ArQule, its
Affiliates or their respective directors, employees or agents as a result of:
(a) actual or asserted violations of any applicable law or regulation by Wyeth-
Ayerst, its Affiliates, sublicensees or third party manufacturers by virtue of
which the Royalty-Bearing Products manufactured, distributed or sold shall be
alleged or determined to be adulterated, misbranded, mislabeled or otherwise not
in compliance with such applicable law or regulation; (b) claims for bodily
injury, death or property damage attributable to the manufacture, distribution,
sale or use of the Royalty-Bearing Products by Wyeth-Ayerst, its Affiliates,
sublicensees or third party manufacturers; or (c) a recall ordered by a
governmental agency, or required by a confirmed failure, of Royalty-Bearing
Products manufactured, distributed, or sold by Wyeth-Ayerst, its Affiliates,
sublicensees or third party manufacturers as reasonably determined by the
Parties hereto.

     11.2. CROSS-INDEMNITY OBLIGATIONS. Each Party (the "Indemnitor") agrees to
defend, indemnify and hold the other Party, its Affiliates and their respective
directors, officers, employees and agents (the "Indemnitee") harmless from all
costs, judgments, liabilities and damages assessed by a court of competent
jurisdiction arising from claims asserted by a third party against the
Indemnitee as a result of a breach by the Indemnitor of any of its respective
representations and warranties made pursuant to Section 10.1 or 10.2 hereof.

     11.3. PROCEDURE. In the event that an Indemnitee or any of its Affiliates
or their respective employees or agents intends to claim indemnification under
this Article 11, such Party shall promptly notify the Indemnitor of any loss,
claim, damage, liability or action in respect of which the Indemnitee intends to
claim such indemnification, and the Indemnitor shall assume the defense thereof
with counsel mutually satisfactory to the Parties; provided, however, that an
Indemnitee shall have the right to retain its own counsel, with the fees and
expenses to be paid by Indemnitor, if representation of such Indemnitee by the
counsel retained by the Indemnitor would be inappropriate due to actual or
potential differing interests between such Indemnitee and any other Party
represented by such counsel in such proceedings. The indemnity agreement in this
Article 11 shall not apply to amounts paid in settlement of any loss, claim,
damage, liability or action if such settlement is effected without the consent
of the Indemnitor, which consent shall not be withheld unreasonably. The failure
to deliver notice to the Indemnitor within a reasonable time after the
commencement of any such action, if prejudicial to its ability to defend such
action, shall relieve the Indemnitor of

                                       25
<PAGE>   31

any liability to the Indemnitee under this Article 11, but the omission so to
deliver notice to the Indemnitor will not relieve it of any liability that it
may have to any Indemnitee otherwise than under this Article 11. The Indemnitee
under this Article 11, its employees and agents, shall cooperate fully with the
Indemnitor and its legal representatives in the investigation of any action,
claim or liability covered by this indemnification.

     11.4. INSURANCE. Wyeth-Ayerst shall maintain appropriate product liability
insurance or self-insurance with respect to development, manufacture and sales
of the Royalty-Bearing Products by Wyeth-Ayerst in such amount as Wyeth-Ayerst
customarily maintains with respect to sales of its other products. Wyeth-Ayerst
shall each maintain such insurance for so long as it continues to manufacture or
sell the Royalty-Bearing Products, and thereafter for so long as Wyeth-Ayerst
maintains insurance for itself covering such manufacture or sales.


12. TERM AND TERMINATION.

     12.1. TERM. This Agreement shall commence on the Effective Date and shall
remain in effect until the expiration of the last Royalty Period covering any
Royalty-Bearing Product, unless earlier terminated as provided in this Article
12.

     12.2. BREACH OF PAYMENT OBLIGATIONS. In the event that Wyeth-Ayerst fails
to make timely payment of any amounts due to ArQule under this Agreement, ArQule
may terminate this Agreement upon ***** days written notice to Wyeth-Ayerst,
unless Wyeth-Ayerst pays all past-due amounts within such ***** notice period.

     12.3. MATERIAL BREACH. In the event that either Party commits a material
breach of any of its obligations under this Agreement (other than as provided in
Section 12.2) and such Party fails (i) to remedy that breach within ***** days
after receiving written notice thereof from the other Party or (ii) to commence
dispute resolution pursuant to Section 13.4, within ***** after receiving
written notice of that breach from the other Party, the other Party may
immediately terminate this Agreement upon written notice to the breaching Party.
In the event that a satisfactory resolution of a clear pattern of false positive
screening results attributable to the quality of Mapping Array(TM) Compounds,
and/or consistent inability to reproduce Active ArQule Compounds in accordance
with the Mapping Array(TM) resynthesis performance criteria as set forth in
Section 3.6, cannot be achieved, then Wyeth-Ayerst shall have the right to
terminate the Mapping Array(TM) Program in accordance with this Section 12.3. In
the event that ArQule fails to complete, except under circumstances not
reasonably within ArQule's control, by the end of the 1998 Contract Year at
least ***** Directed Array(TM) Programs out of the sum of (a) the ***** Directed
Array(TM) Programs commenced during the 1997 Contract Year, and (b) the *****
Directed Array(TM) Programs commenced during the 1998 Contract Year, all *****
of which had been timely approved by the Research Committee, then Wyeth-Ayerst
shall have the right to terminate the Directed Array(TM) Program in accordance
with this Section 12.3.
        
     12.4. INSOLVENCY. Either Party may terminate this Agreement immediately
upon notice to the other Party in the event of (i) the filing by the other Party
of a petition in

* Confidential Treatment has been requested for the marked portions of this
  agreement.

                                       26
<PAGE>   32

bankruptcy or for liquidation; (ii) the request for or appointment of a receiver
for the other Party; (iii) execution upon any portion of the other Party's
business or assets; (iv) the other Party's arrangement with or assignment for
the benefit of creditors; or (v) the other Party becoming unable to meet its
obligations as they become due.

     12.5. CHANGE OF CONTROL. In the event that ArQule is acquired by a
competitor of Wyeth-Ayerst, Wyeth-Ayerst may (i) terminate the Mapping Array(TM)
Program upon ***** months written notice to ArQule, and/or (ii) terminate any
Directed Array Program upon ***** months written notice to ArQule, subject to
the payment of all accrued and unpaid payments, including, without limitation,
Mapping Array(TM) Program (as provided for in this Section 12.5), Directed(TM)
Array Program, Research, and royalty payments accrued or accruing in the future.
In the event Wyeth-Ayerst terminates the Mapping Array(TM) Program pursuant to
this Section 12.5, then Wyeth-Ayerst shall pay ArQule a pro-rated Mapping
Array(TM) subscription fee equal to the sum of ***** . In the event that
Wyeth-Ayerst terminates the Directed Array(TM) Program pursuant to this Section
12.5, Wyeth-Ayerst shall be under no obligation to begin any new Directed
Array(TM) Programs after giving notice of such termination. In the event of
such acquisition, ArQule will keep confidential Wyeth-Ayerst Confidential
Information, including, without limitation, the identity and number of the
Directed Array Targets and Licensed Compounds, from its parent company, and any
employee or consultant thereof (except former ArQule employees and consultants)
for a period of ***** years.
        
     12.6. EFFECT OF TERMINATION. Termination of this Agreement shall not
relieve the Parties of any obligation accruing prior to such termination. The
provisions of Article 6, Sections 7.1, 7.3, 7.6, Article 8 (with respect only to
the payment of milestone payments and royalties accrued at the time of or after
termination), Article 9, Article 11 and Article 13 shall survive the expiration
or termination of this Agreement. Wyeth-Ayerst shall have the right to reserve
or license pursuant to Article 3 or 4, any Active Compound disclosed to ArQule
pursuant to Section 3.1 prior to termination of this Agreement, subject to all
applicable terms and conditions of this Agreement, which shall also survive
termination of this Agreement with respect to such compound. All licenses
granted pursuant to Section 5.2 with respect any Licensed Compound shall survive
termination of this Agreement subject to all applicable terms and conditions of
this Agreement, which shall also survive termination of this Agreement with
respect to such Licensed Compound. Upon termination of this Agreement, the
Parties shall be obliged to take, maintain, and update an inventory of all
payments due ArQule under Articles 3, 4 and 8 of this Agreement.


* Confidential treatment has been requested for the marked portions of this
agreement 


                                       27
<PAGE>   33

13. MISCELLANEOUS.

     13.1. RELATIONSHIP OF PARTIES. Nothing in this Agreement is intended or
shall be deemed to constitute a partnership, agency, employer-employee or joint
venture relationship between the Parties. No Party shall incur any debts or make
any commitments for the other, except to the extent, if at all, specifically
provided therein.

     13.2. PUBLICITY. Neither Party shall use the name of the other Party or
reveal the terms of this Agreement in any publicity or advertising without the
prior written approval of the other Party, except that (i) either Party may use
the text of a written statement approved in advance by both Parties without
further approval, (ii) either Party shall have the right to identify the other
Party and to disclose the terms of this Agreement as required by applicable
securities laws or other applicable law or regulation, and (iii) either Party
may use the name of the other Party and reveal the existence of this Agreement
as long as such statements do not disclose the terms of this Agreement. In any
disclosure of this Agreement to a government agency under the preceding
sentence, the disclosing party shall request confidential treatment of the
sensitive terms and conditions hereof, such as the financial terms of this
Agreement, and shall provide such confidential treatment request to the other
party for review and comment prior to filing.

     13.3. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the Commonwealth of Massachusetts without regard to
its conflict of laws provisions.

     13.4. DISPUTE RESOLUTION PROCEDURES.

               (a) The Parties hereby agree that they will attempt in good faith
     to resolve any controversy, claim or dispute ("Dispute") arising out of or
     relating to this Agreement promptly by negotiations between the  ***** .
     Any such Dispute which is not settled by the Parties within fifteen (15)
     days after notice of such Dispute is given by one Party to the other in
     writing shall be referred to the ***** *** *** *****  who are authorized
     to settle such Disputes on behalf of their respective companies ("*****").
     The ***** will meet for negotiations within fifteen (15) days of the end
     of the 15 day negotiation period referred to above, at a time and place
     mutually acceptable to both ***** . If the Dispute has not been resolved
     within thirty (30) days after the end of the 15 day negotiation period
     referred to above (which period may be extended by mutual agreement),
     subject to any rights to injunctive relief and unless otherwise
     specifically provided for herein, any Dispute will be settled first by
     non-binding mediation as described in subsection (b) below.  

               (b) Any Dispute which is not resolved by the Parties within the
     time period described in subsection (a) shall be submitted to an
     alternative dispute resolution process ("ADR"). Within five (5) business
     days after the expiration of the

* Confidential Treatment has been requested for the marked portions of this
  agreement.


                                       28
<PAGE>   34

     thirty (30) day period set forth in subsection (a), each Party shall select
     for itself a representative with the authority to bind such Party and shall
     notify the other Party in writing of the name and title of such
     representative. Within ten (10) business days after the date of delivery of
     such notice, the representatives shall schedule a date for engaging in
     non-binding ADR with a neutral mediator or dispute resolution firm mutually
     acceptable to both representatives. Any such mediation shall be held in
     Boston, Massachusetts. Thereafter, the representatives of the Parties shall
     engage in good faith in an ADR process under the auspices of such
     individual or firm. If the representatives of the Parties have not been
     able to resolve the Dispute within thirty (30) business days after the
     conclusion of the ADR process, the Parties shall be free to bring an action
     in any court of competent jurisdiction to settle the Dispute. If the
     representatives of the Parties resolve the dispute within the thirty (30)
     day period set forth above, then such resolution shall be binding upon the
     Parties.

               (c) Nothing contained in this Section or any other provisions of
     this Agreement shall be construed to limit or preclude a Party from
     bringing any action in any court of competent jurisdiction for injunctive
     or other provisional relief to compel the other Party to comply with its
     obligations hereunder. The Parties hereby irrevocably consent to submit to
     the jurisdiction of the courts of the Commonwealth of Massachusetts and/or
     any other court having jurisdiction for this purpose.

     13.5. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, and all of which
together shall be deemed to be one and the same instrument.

     13.6. HEADINGS. All headings in this Agreement are for convenience only and
shall not affect the meaning of any provision hereof.

     13.7. BINDING EFFECT. This Agreement shall inure to the benefit of and be
binding upon the Parties, their Affiliates, and their respective lawful
successors and assigns.

     13.8. ASSIGNMENT. This Agreement may not be assigned by either Party
without the prior written consent of the other Party, except that either Party
may assign this Agreement to a successor in connection with the merger,
consolidation, or sale of all or substantially all of its assets or that portion
of its business pertaining to the subject matter of this Agreement.

     13.9. NOTICES. All notices, requests, demands and other communications
required or permitted to be given pursuant to this Agreement shall be in writing
and shall be deemed to have been duly given upon the date of receipt if
delivered by hand, recognized international overnight courier, confirmed
facsimile transmission, or registered or certified mail, return receipt
requested, postage prepaid to the following addresses or facsimile numbers:

                                       29
<PAGE>   35


If to Wyeth-Ayerst:                                If to ArQule:

Wyeth-Ayerst Laboratories                          ArQule, Inc.
555 E. Lancaster Pike                              200 Boston Avenue, Suite 3600
St. Davids, PA  19087                              Medford, MA  02155
Attention: Sr. V.P. Global Business                Attention:  Eric B. Gordon
                  Development                      Tel: (617) 395-4100
Tel: (610) 971-5809                                Fax: (617) 395-1225
Fax: (610) 688-9498
                                                   with a copy to:
with a copy to:
American Home Products Corp.                       Palmer & Dodge
5 Giralda Farms                                    One Beacon Street
Madison, NJ  07940                                 Boston, MA  02108
Attention: Associate                               Attention:  Michael Lytton,
General Counsel                                    Esquire
Tel:  (973) 660-6150                               Tel: (617) 573-0327
Fax:  (973) 660-7155                               Fax: (617) 227-4420


     Either Party may change its designated address and facsimile number by
notice to the other Party in the manner provided in this Section.

     13.10. AMENDMENT AND WAIVER. This Agreement may be amended, supplemented,
or otherwise modified only by means of a written instrument signed by both
Parties. Any waiver of any rights or failure to act in a specific instance shall
relate only to such instance and shall not be construed as an agreement to waive
any rights or fail to act in any other instance, whether or not similar.

     13.11. SEVERABILITY. In the event that any provision of this Agreement
shall, for any reason, be held to be invalid or unenforceable in any respect,
such invalidity or unenforceability shall not affect any other provision hereof,
and the Parties shall negotiate in good faith to modify the Agreement to
preserve (to the extent possible) their original intent.

     13.12. ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
between the Parties with respect to the subject matter hereof and supersedes all
prior agreements or understandings between the Parties relating to the subject
matter hereof.

     13.13. FORCE MAJEURE. Neither Party shall be held liable or responsible to
the other Party, nor be deemed to be in breach of this Agreement, for failure or
delay in fulfilling or performing any provisions of this Agreement when such
failure or delay is caused by or results from any cause whatsoever outside the
reasonable control of the Party concerned including, but not limited to, fire,
explosion, breakdown of plant, strike, lock-out, labor disputes, casualty or
accident, lack or failure of transportation facilities, flood, lack or failure
of sources of supply or of labor, raw materials or energy, civil commotion,
embargo, any law, regulation, decision, demand or requirement of any national or
local government or authority. The Party claiming relief shall, without delay,
notify the other Party by registered

                                       30
<PAGE>   36

airmail or by telefax of the interruption and cessation thereof and shall use
its best efforts to remedy the effects of such hindrance with all reasonable
dispatch. The onus of proving that any such Force Majeure event exists shall
rest upon the Party so asserting. During the period that one Party is prevented
from performing its obligations under this Agreement due to a Force Majeure
event, the other Party may, in its sole discretion, suspend any obligations that
relate thereto. Upon cessation of such Force Majeure event the Parties hereto
shall use their best efforts to make up for any suspended obligations. If such
Force Majeure event is anticipated to continue, or has existed for nine (9)
consecutive months or more, this Agreement may be forthwith terminated by either
Party by registered airmail or by telefax. In case of such termination the
terminating Party will not be required to pay to the other Party any indemnity
whatsoever.

     13.14. HART-SCOTT-RODINO ACT. If required by law, the parties will, at
their own expense, prepare and make appropriate filings under Title II of the
Hart-Scott-Rodino Antitrust Improvement Act of 1976, as amended, and the rules
and regulations promulgated thereunder (16 C.F.R. 801.1 et. seq.) (the "Act") as
soon as reasonably practicable. The parties shall co-operate in the antitrust
clearance process and agree to furnish promptly to the FTC and the Antitrust
Division of the Department of Justice any additional information reasonably
requested by them in connection with such filings.


              [THE REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

                                       31
<PAGE>   37


     IN WITNESS WHEREOF, the undersigned have duly executed and delivered this
Agreement as a sealed instrument effective as of the date first above written.



AMERICAN HOME PRODUCTS CORPORATION                ARQULE, INC.



By: /s/ Gerald A. Jibilian                        By: /s/ Eric B. Gordon
    ------------------------------                    --------------------------
Name:  Gerald A. Jibilian                         Name:  Eric B. Gordon
Title: Vice President                             Title: President and
                                                         Chief Executive Officer

                                       32
<PAGE>   38

                                    EXHIBIT A

                                  Research Plan
                                  -------------

Pursuant to Section 1.42 hereof, the initial Research Plan shall be developed by
the Parties within ***** days of the Effective Date and be attached to this
Agreement as EXHIBIT A.

* Confidential Treatment has been requested for the marked portions of this
  agreement.



<PAGE>   39



                                    EXHIBIT B

  Process for Progressing Lead Compounds from Discovery Research to an Approved
  -----------------------------------------------------------------------------
                               IND-Track Compound
                               ------------------


Biological Compounds
- --------------------

*****



* Confidential Treatment has been requested for the marked portions of this
  agreement.


<PAGE>   40




*****




Chemical Criteria
- -----------------



******



* Confidential Treatment has been requested for the marked portions of this
  agreement.




<PAGE>   41

Other Criteria
- --------------

*****



* Confidential Treatment has been requested for the marked portions of this
  agreement.




<PAGE>   42

                           IND-TRACK PROPOSAL DOCUMENT
                           ---------------------------


*****



* Confidential Treatment has been requested for the marked portions of this
  agreement.









<PAGE>   43



                         IND-TRACK COMPOUND PROCESS FLOW
                         -------------------------------




*****




* Confidential Treatment has been requested for the marked portions of this
  agreement.






<PAGE>   44



*****



* Confidential Treatment has been requested for the marked portions of this
  agreement.








<PAGE>   1
                         COMMON STOCK PURCHASE AGREEMENT

                                     between

                                  ARQULE, INC.

                                       and

                       AMERICAN HOME PRODUCTS CORPORATION


                            dated as of July 3, 1997





<PAGE>   2


<TABLE>
<CAPTION>

                                TABLE OF CONTENTS

        <S>                      <C>                                                                              <C>
          SECTION 1.       AUTHORIZATION OF SALE OF THE SHARES..................................................  1
                           -----------------------------------

          SECTION 2.       SALE OF THE SHARES...................................................................  1
                           ------------------

          SECTION 3.       DELIVERY OF THE SHARES AT THE CLOSING................................................  2
                           -------------------------------------

          SECTION 4.       REPRESENTATIONS, WARRANTIES AND COVENANTS OF ARQULE..................................  2
                           ---------------------------------------------------
                  4.1      ORGANIZATION AND QUALIFICATION.......................................................  2
                           ------------------------------
                  4.2      AUTHORIZED CAPITAL STOCK.............................................................  2
                           ------------------------
                  4.3      CONSENTS; DUE EXECUTION; DELIVERY AND PERFORMANCE OF THE AGREEMENT...................  2
                           ------------------------------------------------------------------
                  4.4      ISSUANCE, SALE AND DELIVERY OF THE SHARES............................................  3
                           -----------------------------------------
                  4.5      EXEMPT TRANSACTION...................................................................  3
                           ------------------
                  4.6      COMPLIANCE WITH RULE 144.............................................................  3
                           ------------------------
                  4.7      DISCLOSURE...........................................................................  3
                           ----------
                  4.8      ADDITIONAL INFORMATION...............................................................  4
                           ----------------------
                  4.9      NO MATERIAL CHANGES..................................................................  4
                           -------------------
                  4.10     LITIGATION...........................................................................  4
                           ----------
                  4.11     VOTING ARRANGEMENTS..................................................................  4
                           -------------------
                  4.12     NASDAQ NATIONAL MARKET DESIGNATION...................................................  4
                           ----------------------------------

          SECTION 5.       REPRESENTATIONS, WARRANTIES AND COVENANTS OF AHPC....................................  4
                           -------------------------------------------------
                  5.1      INVESTMENT CONSIDERATIONS............................................................  4
                           -------------------------
                  5.2      DUE EXECUTION, DELIVERY AND PERFORMANCE OF THE AGREEMENT.............................  5
                           --------------------------------------------------------

          SECTION 6.       CONDITIONS TO THE OBLIGATIONS OF THE PURCHASERS......................................  6
                           -----------------------------------------------
                  6.1      ACCURACY OF REPRESENTATIONS AND WARRANTIES...........................................  6
                           ------------------------------------------
                  6.2      PERFORMANCE..........................................................................  6
                           -----------
                  6.3      OPINION OF COUNSEL...................................................................  6
                           ------------------
                  6.4      CERTIFICATES AND DOCUMENTS...........................................................  6
                           --------------------------
                  6.5      OTHER MATTERS........................................................................  7
                           -------------

          SECTION 7.       CONDITIONS TO THE OBLIGATIONS OF ARQULE..............................................  7
                           ---------------------------------------
                  7.1      ACCURACY OF REPRESENTATIONS AND WARRANTIES...........................................  7
                           ------------------------------------------
                  7.2      CERTIFICATES AND DOCUMENTS...........................................................  7
                           --------------------------
                  7.3      PERFORMANCE..........................................................................  7
                           -----------
                  7.4      OTHER MATTERS........................................................................  7
                           -------------

          SECTION 8.       SURVIVAL OF REPRESENTATIONS, WARRANTIES AND AGREEMENTS; ASSIGNABILITY
                             OF RIGHTS...........................................................................  8

</TABLE>
                                       (i)

<PAGE>   3

<TABLE>
<CAPTION>

         <S>                <C>                                                                                   <C>
          SECTION 9.       INCIDENTAL REGISTRATION..............................................................  8
                           -----------------------
                  9.1      REGISTRATION OF SHARES...............................................................  8
                           ----------------------
                  9.2      ALLOCATION OF EXPENSES...............................................................  9
                           ----------------------
                  9.3      INDEMNIFICATION......................................................................  9
                           ---------------
                  9.4      TERMINATION.......................................................................... 11
                           -----------

          SECTION 10.      MISCELLANEOUS........................................................................ 11
                           -------------                
                  10.1     NOTICES.............................................................................. 11
                           -------
                  10.2     ENTIRE AGREEMENT..................................................................... 12
                           ----------------
                  10.3     ASSIGNMENT........................................................................... 12
                           ----------
                  10.4     AMENDMENTS AND WAIVERS............................................................... 12
                           ----------------------
                  10.5     HEADINGS............................................................................. 12
                           --------
                  10.6     SEVERABILITY......................................................................... 12
                           ------------
                  10.7     GOVERNING LAW........................................................................ 12
                           -------------
                  10.8     COUNTERPARTS......................................................................... 12
                           ------------
                  10.9     EXPENSES............................................................................. 13
                           --------
                  10.10    PUBLICITY............................................................................ 13
                           ---------

         EXHIBIT A.............................................................................................. 15
         ---------
</TABLE>


                                      (ii)

<PAGE>   4



                         COMMON STOCK PURCHASE AGREEMENT


     THIS COMMON STOCK PURCHASE AGREEMENT dated as of July 3, 1997 (the
"Agreement") is made between ARQULE, INC., a corporation organized under the
laws of the State of Delaware ("ArQule" or the "Company"), and American Home
Products Corporation ("AHPC"), a corporation organized under the laws of the
State of Delaware.

                                  R E C I T A L

     ArQule desires to sell to AHPC, and AHPC desires to purchase from ArQule,
shares of ArQule's common stock on the terms and conditions described herein and
in reliance upon the representations, warranties and agreements contained
herein.

     NOW THEREFORE, in consideration of the premises and of the covenants herein
contained, the parties hereto mutually agree as follows:

     SECTION 1. AUTHORIZATION OF SALE OF THE SHARES. Subject to the terms and
conditions of this Agreement, ArQule has authorized the sale to AHPC of that
number of shares of the common stock, par value $0.01 per share (the "Common
Stock"), of ArQule equal to the quotient obtained by dividing $2,000,000 by the
Per Share Price of the shares of Common Stock as defined in Section 2 hereof.
Collectively, the shares of Common Stock which shall be purchased pursuant to
this Section 1 are referred to herein as the "Shares."

     SECTION 2. SALE OF THE SHARES. ArQule shall sell to AHPC, and AHPC shall
purchase from ArQule, upon the terms and conditions hereinafter set forth, the
Shares, at a price per share equal to 1.2 multiplied by the average of the
closing price of the Common Stock (the "Closing Price") on the NASDAQ National
Market (or on a principal national securities exchange on which the Common Stock
is listed or admitted to trading) for the twenty (20) trading days measured up
to three (3) trading days prior to the date of purchase as reported in the WALL
STREET JOURNAL subject to any equitable adjustments for recapitalizations, stock
dividends, distributions, or combinations affecting the Common Stock during such
20 day period (as so determined, the "Per Share Price"). The aggregate purchase
price for the Shares (the "Aggregate Purchase Price") shall be $2,000,000. In
the event that the Common Stock is not listed or traded on any such exchange or
the NASDAQ National Market, then the Closing Price shall be the bid price per
share on NASDAQ Small-Cap Market, or in the sole good faith discretion of the
Board of Directors of the Company, any other over-the-counter market, including
the OTC Bulletin Board, which reports bid, asked and last sale prices and volume
of sales. If at any time such quotations are not available, the current fair
market value of a share of Common Stock shall be the highest price per share
which the Company could obtain from a willing buyer (not a current employee or
director) for shares of Common Stock sold by the Company, from authorized but
unissued shares, as determined in good faith by the Board of Directors of the
Company, unless the Company shall become subject to a merger, acquisition or
other consolidation pursuant to which the Company is not the surviving party, in
which case the current fair market value of a share of Common Stock shall be
deemed to be the value received by the


<PAGE>   5



holders of the Company's Common Stock for each share of Common Stock pursuant to
the Company's acquisition.

     SECTION 3. DELIVERY OF THE SHARES AT THE CLOSING. The closing of the
purchase and sale of the Shares (the "Closing") shall occur during the first
half of 1998 on a date chosen by AHPC (i.e., no later than June 30, 1998) or at
such other time and date and at a place to be agreed upon by ArQule and AHPC
(the "Closing Date"). AHPC shall deliver notice of Closing no less than 30 days
prior to the Closing Date. ArQule shall not repurchase any of its Common Stock
between the date notice of Closing is delivered and the Closing Date other than
as a result of pre-existing obligations or agreements for the repurchase of
non-material amounts of its Common Stock. Subject to the terms and conditions of
this Agreement, at the Closing, AHPC shall pay to ArQule an amount in cash or by
wire transfer equal to the Aggregate Purchase Price and ArQule shall deliver to
AHPC one or more stock certificates in such denomination and registered in the
name of AHPC, or in such nominee name(s) as designated by AHPC, representing the
number of Shares being purchased.


     SECTION 4. REPRESENTATIONS, WARRANTIES AND COVENANTS OF ARQULE. ArQule
hereby represents and warrants to, and covenants with, AHPC as follows:

          4.1 ORGANIZATION AND QUALIFICATION. ArQule is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware and has all requisite corporate power and authority to conduct its
business as currently conducted and proposed to be conducted. ArQule is duly
qualified to transact business and is in good standing in each jurisdiction in
which the failure to so qualify would reasonably be expected to have a material
adverse effect on the business, operations, properties, assets, prospects or
conditions (financial or otherwise) of ArQule (a "Material Adverse Effect").
Except as otherwise disclosed to AHPC prior to the Closing, ArQule has no
subsidiaries.

          4.2 AUTHORIZED CAPITAL STOCK. ArQule is authorized to issue 30,000,000
shares of Common Stock, and 1,000,000 shares of undesignated preferred stock,
$0.01 par value per share (the "Preferred Stock"). As of April 14, 1997, there
were 11,790,862 shares of Common Stock and no shares of Preferred Stock
outstanding. No shares of capital stock, or securities convertible into or
exercisable for capital stock or other rights affecting the capital stock, have
been issued since such date except for issuances pursuant to ArQule's equity
compensation plans or pursuant to outstanding options, warrants or rights, in
each case as described in the SEC filings. All outstanding shares of Common
Stock have been duly authorized and validly issued and are fully paid and
non-assessable; and none of the outstanding shares of Common Stock were issued
in violation of the preemptive rights, if any, of any stockholders of ArQule.

          4.3 CONSENTS; DUE EXECUTION; DELIVERY AND PERFORMANCE OF THE
AGREEMENT. ArQule has all corporate power and authority to execute, deliver and
perform its obligations

                                        2
<PAGE>   6

under this agreement and to issue the Shares. ArQule's execution, delivery and
performance of this Agreement (a) has been duly authorized under Delaware law by
all requisite corporate action by ArQule, (b) will not violate any law or the
Amended and Restated Certificate of Incorporation or Amended and Restated
By-laws of ArQule or any other corporation of which ArQule owns at least 50% of
the outstanding voting stock (an "ArQule Subsidiary") or any provision of any
material indenture, mortgage, agreement, contract or other material instrument
to which ArQule or any ArQule Subsidiary is a party or by which any of their
respective properties or assets is bound as of the date hereof, and (c) will not
require any consent by any person under, constitute or result (upon notice or
lapse of time or both) in a breach of any term, condition or provision of, or
constitute a default or give rise to any right of termination or acceleration
under any such indenture, mortgage, agreement, contract or other material
instrument or result in the creation or imposition of any material lien,
security interest, mortgage, pledge, charge or other encumbrance upon any
properties or assets of ArQule or any ArQule Subsidiary. Upon its execution and
delivery, and assuming the valid execution thereof by AHPC, the Agreement will
constitute a valid and binding obligation of ArQule, enforceable against ArQule
in accordance with its terms, except as enforceability may be limited by
applicable bankruptcy, insolvency, reorganization, moratorium or similar laws
affecting creditors' and contracting parties' rights generally and except as
enforceability may be subject to general principles of equity (regardless of
whether such enforceability is considered in a proceeding in equity or at law).

          4.4 ISSUANCE, SALE AND DELIVERY OF THE SHARES. When issued and paid
for, the Shares to be sold hereunder by ArQule will be validly issued and
outstanding, fully paid and non-assessable.

          4.5 EXEMPT TRANSACTION. Subject to the accuracy of AHPC's
representations in Section 5.1 of this Agreement, the issuance of the Shares
will constitute a transaction exempt from the registration requirements of
Section 5 of the Securities Act of 1933, as amended (the "Securities Act") in
reliance upon Section 4(2) of the Securities Act and the regulations promulgated
pursuant thereto.

          4.6 COMPLIANCE WITH RULE 144. At the written request of AHPC at any
time and from time to time, ArQule shall furnish to AHPC, within three days
after receipt of such request, a written statement confirming ArQule's
compliance with the filing requirements of the Securities and Exchange
Commission (the "SEC") set forth in SEC Rule 144 as amended from time to time.

          4.7 DISCLOSURE. Neither this Agreement, nor any other items prepared
or supplied to AHPC by or on behalf of ArQule with respect to the transactions
contemplated hereby contain any untrue statement of a material fact or omit a
material fact necessary to make each statement contained herein or therein not
misleading. There is no fact which ArQule has not disclosed to AHPC in writing
and of which any of its directors or executive officers is aware (other than
general economic conditions) which has had or would reasonably be expected to
have a Material Adverse Effect upon the business prospects of ArQule. ArQule
further warrants that the quarterly report for the quarter ending March 31, 1997
on Form 10-Q dated May 9, 1997 does not contain any untrue statement of a
material

                                        3
<PAGE>   7

fact and does not omit to state any material fact necessary to make the
statements therein not misleading as of the date hereof.

          4.8 ADDITIONAL INFORMATION. All reports filed by ArQule with the SEC
pursuant to the reporting requirements of the Securities Exchange Act of 1934,
as amended (the "Exchange Act"), when filed, did not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading. ArQule has made all
filings with the SEC which it is required to make, and ArQule has not received
any request from the SEC to file any amendment or supplement to any such
reports. ArQule agrees that, as long as the License Agreement between ArQule and
AHPC (acting through its Wyeth-Ayerst Research division), dated as of the date
hereof, is in effect, it will furnish to AHPC all annual and quarterly reports
generally furnished to ArQule's stockholders in the normal course, and SEC
filings upon request.

          4.9 NO MATERIAL CHANGES. As of the date hereof, there has been no
material adverse change in the business, operations, properties, assets,
prospects or condition (financial or otherwise) of ArQule since the filing date
of ArQule's last report with the Securities and Exchange Commission pursuant to
the reporting requirements of the Exchange Act.

          4.10 LITIGATION. There is no action, suit or proceeding pending, or,
to ArQule's knowledge, threatened, against ArQule (a) which questions the
validity of this Agreement or the ability of the Company to consummate the
transactions contemplated hereby or (b) which, singly or in the aggregate, if
the subject of unfavorable decision, ruling or finding, would have a Material
Adverse Effect on the business, properties, prospects, operations, or financial
condition of ArQule, in each case as described in the SEC filings.

          4.11 VOTING ARRANGEMENTS. To the best of ArQule's knowledge, there are
no outstanding stockholder agreements, voting trusts, proxies or other
arrangements or understandings among the stockholders of ArQule relating to the
voting of their respective shares.

          4.12 NASDAQ NATIONAL MARKET DESIGNATION. The Common Stock of ArQule is
listed on the Nasdaq National Market and ArQule knows of no reason or set of
facts which is likely to result in the delisting of the Common Stock by the
Nasdaq National Market or the inability of such stock to continue to be included
in the Nasdaq National Market.


     SECTION 5. REPRESENTATIONS, WARRANTIES AND COVENANTS OF AHPC.

          5.1 INVESTMENT CONSIDERATIONS. AHPC represents and warrants to, and
covenants with, ArQule that:

                    (a) AHPC is knowledgeable, sophisticated and experienced in
          making, and is qualified to make, decisions with respect to
          investments in shares presenting an investment decision like that
          involved in the purchase of

                                        4
<PAGE>   8

          the Shares, including investments in securities issued by companies
          comparable to ArQule, and has requested, received, reviewed and
          considered all information it deems relevant in making an informed
          decision to purchase the Shares;

                    (b) AHPC is acquiring the Shares in the ordinary course of
          its business and for its own account for investment only and with no
          present intention of distributing any of such Shares or any
          arrangement or understanding with any other persons regarding the
          distribution of such Shares;

                    (c) AHPC understands that the Shares are "restricted
          securities" under the federal securities laws inasmuch as they are
          being acquired from ArQule in a transaction not involving a public
          offering and that under such laws and applicable regulations such
          securities may be resold without registration under the Securities Act
          only in certain limited circumstances. In this connection AHPC
          represents that it is familiar with SEC Rule 144, as presently in
          effect, and understands the resale limitations imposed thereby and by
          the Securities Act;

                    (d) AHPC will not, directly or indirectly, offer, sell,
          pledge, transfer or otherwise dispose of (or solicit any offers to
          buy, purchase or otherwise acquire or take a pledge of) any of the
          Shares except in compliance with the Securities Act, and the rules and
          regulations promulgated thereunder;

                    (e) AHPC qualifies as an "accredited investor" within the
          meaning of Rule 501(a)(3) of Regulation D promulgated under the
          Securities Act and is not a resident of any of the United States of
          America; and

                    (f) It is understood that the certificates evidencing the
          Shares shall bear the following legend unless and until the resale of
          the Shares pursuant to an effective Registration Statement or until
          the Shares may be sold under Rule 144 without restrictions:

     THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933.
     THEY MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED OR HYPOTHECATED IN THE
     ABSENCE OF A REGISTRATION STATEMENT IN EFFECT WITH RESPECT TO THE
     SECURITIES UNDER SUCH ACT OR, IF REQUESTED BY ARQULE, AN OPINION OF COUNSEL
     REASONABLY SATISFACTORY TO ARQULE AND ITS COUNSEL, THAT SUCH REGISTRATION
     IS NOT REQUIRED UNDER SUCH ACT.

          5.2 DUE EXECUTION, DELIVERY AND PERFORMANCE OF THE AGREEMENT. AHPC
further represents and warrants to, and covenants with, ArQule that (a) AHPC is
a corporation duly organized, validly existing and in good standing under the
laws of the State of Delaware and has full right, power, authority and capacity
to enter into this Agreement and to consummate the transactions contemplated
hereby and has taken all necessary action to

                                        5
<PAGE>   9

authorize the execution, delivery and performance of this Agreement, (b) the
execution, delivery and performance of this Agreement will not violate any law
or the charter documents of AHPC or any other corporation of which AHPC owns at
least 50% of the outstanding voting stock (a "AHPC Subsidiary") or any provision
of any material indenture, mortgage, agreement, contract or other material
instrument to which AHPC or any AHPC Subsidiary is a party or by which AHPC, any
AHPC Subsidiary, or any of their respective properties or assets is bound as of
the date hereof, or result in a breach of or constitute (upon notice or lapse of
time or both) a default under any such indenture, mortgage, agreement, contract
or other material instrument or result in the creation or imposition of any
material lien, security interest, mortgage, pledge, charge or encumbrance upon
any assets of AHPC or any AHPC Subsidiary, and (c) upon the execution and
delivery of this Agreement, and assuming the valid execution thereof by ArQule,
this Agreement shall constitute a valid and binding obligation of AHPC
enforceable in accordance with its terms, except as enforceability may be
limited by applicable bankruptcy, insolvency, reorganization, moratorium or
similar laws affecting creditors' and contracting parties' rights generally and
except as enforceability may be subject to general principles of equity
(regardless of whether such enforceability is considered in a proceeding in
equity or at law).


     SECTION 6. CONDITIONS TO THE OBLIGATIONS OF THE PURCHASERS.

          The obligations of AHPC under this Agreement are subject to the
fulfillment, or the waiver by AHPC, of the conditions set forth in this Section
6 on or before the Closing Date.

          6.1 ACCURACY OF REPRESENTATIONS AND WARRANTIES. Each representation
and warranty of ArQule contained in this Agreement shall be true on and as of
the Closing Date with the same effect as though such representation and warranty
had been made on and as of that date.

          6.2 PERFORMANCE. ArQule shall have performed and complied with all
agreements and conditions contained in this Agreement required to be performed
or complied with by ArQule prior to or at the Closing.

          6.3 OPINION OF COUNSEL. AHPC shall have received an opinion from
Palmer & Dodge LLP (or other outside counsel chosen by ArQule and reasonably
acceptable to AHPC), counsel to ArQule dated as of the Closing Date, addressed
to AHPC, and substantially in the form attached hereto as EXHIBIT A.

     6.4 CERTIFICATES AND DOCUMENTS. ArQule shall have delivered to counsel 
to AHPC:

               (a) a certificate of the Secretary or Assistant Secretary of
ArQule dated as of the Closing Date, certifying as to (i) the incumbency of
officers of ArQule executing this Agreement and all other documents executed and
delivered in connection herewith, (ii) a copy of the By-Laws of ArQule, as in
effect on and as of the Closing Date, and (iii) a copy of the resolutions of the
Board of Directors of ArQule authorizing and

                                        6
<PAGE>   10

approving ArQule's execution, delivery and performance of this Agreement, all
matters in connection with this Agreement, and the transactions contemplated
thereby.

               (b) a certificate, executed by the President of ArQule as of the
Closing Date, certifying to the fulfillment of all of the conditions to AHPC's
obligations under this Agreement, as set forth in this Section 6.

          6.5 OTHER MATTERS. All corporate and other proceedings in connection
with the transactions contemplated at the Closing by this Agreement, and all
documents and instruments incident to such transactions, shall be reasonably
satisfactory in substance and form to AHPC and its counsel, and AHPC and its
counsel shall have received all such counterpart originals or certified or other
copies of such documents as they may reasonably request.


         SECTION 7.  CONDITIONS TO THE OBLIGATIONS OF ARQULE.

          The obligations of ArQule under this Agreement are subject to the
fulfillment, or the waiver by ArQule, of the conditions set forth in this
Section 7 on or before the Closing Date.

          7.1 ACCURACY OF REPRESENTATIONS AND WARRANTIES. Each representation
and warranty of AHPC contained in this Agreement shall be true on and as of the
Closing Date with the same effect as though such representations and warranties
had been made on and as of that date.

          7.2 CERTIFICATES AND DOCUMENTS. AHPC shall have delivered to counsel
to ArQule:

               (a) a certificate of the Secretary or Assistant Secretary of AHPC
dated as of the Closing Date, certifying as to the incumbency of officers of
AHPC executing this Agreement and all other documents executed and delivered in
connection herewith.

               (b) a certificate, executed by a duly authorized officer of AHPC
as of the Closing Date, certifying to the fulfillment of all of the conditions
to ArQule's obligations under this Agreement, as set forth in this Section 7.

          7.3 PERFORMANCE. AHPC shall have performed and complied with all
agreements and conditions contained in this Agreement required to be performed
or complied with by AHPC prior to or at the Closing.

          7.4 OTHER MATTERS. All corporate and other proceedings in connection
with the transactions contemplated at the Closing by this Agreement, and all
documents and instruments incident to such transactions, shall be reasonably
satisfactory in substance and form to ArQule and its counsel, and ArQule and its
counsel shall have received all such counterpart originals or certified or other
copies of such documents as they may reasonably request.

                                        7
<PAGE>   11

     SECTION 8. SURVIVAL OF REPRESENTATIONS, WARRANTIES AND AGREEMENTS;
ASSIGNABILITY OF RIGHTS. Notwithstanding any investigation made by any party to
this Agreement, all covenants, agreements, representations and warranties made
by ArQule and AHPC herein, except as otherwise provided herein, shall survive
the execution of this Agreement, the delivery to AHPC of the Shares being
purchased and the payment therefor. Except as otherwise provided herein, (i) the
covenants, agreements, representations and warranties of ArQule made herein
shall bind ArQule's successors and assigns and shall insure to the benefit of
AHPC's successors and assigns and (ii) the covenants, agreements,
representations and warranties of AHPC made herein shall bind AHPC's successors
and assigns and shall insure to the benefit of ArQule's successors and assigns.


     SECTION 9. INCIDENTAL REGISTRATION.

     For the purpose of this Section 9, the term "Registrable Shares" shall mean
all Shares and Common Stock issued pursuant to stock splits, stock dividends and
similar distributions with respect to such Shares.

          9.1 REGISTRATION OF SHARES. ArQule covenants and agrees that it will:

          (a)  Whenever ArQule proposes to file a Registration Statement in
               connection with a public offering of its Common Stock, prior to
               such filing it shall give reasonable advance written notice to
               AHPC of its intention to do so, and upon the written request of
               AHPC which shall be given no later than 30 days after ArQule
               provides such notice (which request shall state the intended
               method of disposition of such Registrable Shares), ArQule shall
               use its best efforts to cause all Registrable Shares which ArQule
               has been requested to register to be registered under the
               Securities Act to the extent necessary to permit their sale or
               other disposition in accordance with the intended methods of
               distribution specified in the request of AHPC; PROVIDED that,
               ArQule shall have the right to postpone or withdraw any
               registration effected pursuant to this Section 9 without
               obligation to AHPC if, in the reasonable opinion of the Board of
               Directors of ArQule, such registration statement would be
               materially detrimental to ArQule.

          (b)  In connection with any offering under this Section 9 involving an
               underwriter, and subject to the next sentence hereof, ArQule
               shall not be required to include any Registrable Shares in such
               underwritten public offer in such quantity as will, in the
               reasonable opinion of the managing underwriter, jeopardize the
               success of the offering by ArQule or materially adversely affect
               the price receivable by ArQule in such offering. If in the
               opinion of the managing underwriter the registration of all, or
               part of, the Registrable Shares which AHPC has requested to be
               included would materially and adversely affect the success or the
               price receivable in such public offering, then ArQule shall be
               required to include in the underwriting only that number of
               Registrable Shares, if any, which the managing underwriter
               believes may be sold without causing such adverse effect,
               PROVIDED, HOWEVER, that Shares

                                        8

<PAGE>   12

               which AHPC has requested to be included in any underwriting
               aggregated with all other third party "piggyback" shares shall be
               no less than 25% of any such offering.

          9.2 ALLOCATION OF EXPENSES. ArQule shall pay the Registration Expenses
for all registrations requested by AHPC pursuant to this Agreement. For purposes
of this Section, the term "Registration Expenses" shall mean all expenses
incurred by ArQule in complying with this Agreement, including, without
limitation, all registration and filing fees, exchange listing fees, printing
expenses, fees and disbursements of counsel for ArQule and one counsel for all
the selling holders of Common Stock pursuant to such registration, out-of-pocket
expenses of ArQule and the underwriters, state Blue Sky fees and expenses, and
the expense of any special audits incident to or required by any such
registration, but excluding underwriting discount and selling commissions and
fees of more than one counsel for such selling holders. Such underwriting
discounts and selling commissions shall be borne pro rata by the selling holders
in accordance with the number of shares of their Common Stock included in such
registration.

          9.3 INDEMNIFICATION.

          (a)  In the event of any registration of any of the Registrable Shares
               under the Securities Act pursuant to this Agreement, then to the
               extent permitted by law ArQule shall indemnify and hold harmless
               the seller of such Registrable Shares and each of its officers,
               directors and employees of such seller, if any, each underwriter
               of such Registrable Shares and each other persons, if any, who
               controls such seller or underwriter within the meaning of the
               Securities Act or the Exchange Act against any losses, claims,
               damages or liabilities, joint or several, to which such seller,
               underwriter or controlling person may become subject under the
               Securities Act, the Exchange Act, state securities laws or
               otherwise, insofar as such losses, claims, damages or liabilities
               (or actions in respect thereof) arise out of or are based upon
               any untrue statement or alleged untrue statement of any material
               fact contained in any Registration Statement under which such
               Registrable Shares were registered under the Securities Act, or
               any preliminary prospectus or final prospectus contained in the
               Registration Statement, or any amendment or supplement to such
               Registration Statement, or arise out of or are based upon the
               omission or alleged omission to state a material fact required to
               be stated therein or necessary to make the statements therein not
               misleading; and ArQule shall reimburse such seller, underwriter
               and each such controlling person for any legal or any other
               expenses reasonably incurred by such seller, underwriter or
               controlling person in connection with investigating or defending
               any such loss, claim, damage, liability or action; PROVIDED,
               HOWEVER, that ArQule shall not be liable in any such cases to the
               extent that such loss, claim, damage or liability arises out of
               or is based upon any untrue statement or omission made in such
               Registration Statement, preliminary prospectus or prospectus, or
               any such amendment or supplement, in reliance upon and in
               conformity with information furnished to ArQule, in writing, by
               or on behalf of such seller, underwriter or controlling person
               specifically for use in the preparation thereof.

                                        9
<PAGE>   13




          (b)  In the event of any registration of any of the Registrable Shares
               under the Securities Act pursuant to this Agreement, then to the
               extent permitted by law, each seller of Registrable Shares
               severally and not jointly, shall indemnify and hold harmless
               ArQule, each of its directors and officers and each underwriter
               (if any) and each person, if any, who controls ArQule or any such
               underwriter within the meaning of the Securities Act or the
               Exchange Act, against any losses, claims, damages or liabilities
               joint or several, to which ArQule, such directors and officers,
               underwriter or controlling person may become subject under the
               Securities Act, Exchange Act, state securities laws or otherwise,
               insofar as such losses, claims, damages or liabilities (or
               actions in respect hereof) arise out of or are based upon any
               untrue statement or alleged untrue statement of a material fact
               contained in any Registration Statement under which Registrable
               Shares were registered under the Securities Act, any preliminary
               prospectus or final prospectus contained in the Registration
               Statement, or any amendment or supplement to the Registration
               Statement, or arise out of or are based upon any omission or
               alleged omission to state a material fact required to be stated
               therein or necessary to make the statements therein not
               misleading, if the statement or omission was made in reliance
               upon and in conformity with information furnished in writing to
               ArQule by or on behalf of such seller specifically for use in
               connection with the preparation of such Registration Statement,
               prospectus, amendment or supplement; PROVIDED, HOWEVER, that the
               obligations of such seller hereunder shall be limited to an
               amount equal to the proceeds to such seller of Registrable Shares
               sold as contemplated herein.

          (c)  Indemnifications of an underwriter pursuant to this Section 9.3
               shall not be interpreted as providing relief of such underwriter
               from any or all of its due diligence obligations. Further, an
               underwriter shall not be entitled to indemnification pursuant to
               this section in the event that it fails to deliver to any seller
               of Registerable Shares any preliminary or final or revised
               prospectus, as required by the Rules and Regulations of the
               Commission. Finally, no indemnification shall be provided
               pursuant to this Section in the event that any error in a
               preliminary prospectus of ArQule is subsequently corrected in the
               final prospectus of ArQule for a particular offering, and such
               final prospectus is delivered to the person seeking indemnity, in
               the case of a claim made under Section 9.3(a), or to all
               purchasers in the offering by ArQule in the case of a claim under
               Section 9.3(b) prior to the date of purchase of the securities.

          (d)  Each party entitled to indemnification under this Section 9.3
               (the Indemnified Party) shall give notice to the party required
               to provide indemnification (the Indemnifying Party) promptly
               after such Indemnified Party has been given notice of a claim as
               to which indemnity may be sought, and shall permit the
               Indemnifying Party to assume the defense of any such claim or any
               litigation resulting therefrom, PROVIDED that counsel for the
               Indemnifying Party, who shall conduct the defense of such claim
               or litigation, shall be approved by the Indemnified Party (whose
               approval shall not be unreasonably withheld or

                                       10
<PAGE>   14

               delayed); and, PROVIDED, FURTHER, that the failure of any
               Indemnified Party to give notice as provided therein shall not
               relieve the Indemnifying Party of its obligations under this
               Agreement except to the extent actually prejudiced. The
               Indemnified Party may participate in such defense at such
               Indemnified Party's expense, PROVIDED, HOWEVER, that the
               Indemnifying Party shall pay such expense if representation of
               such Indemnified Party by the counsel retained by the
               Indemnifying Party would be inappropriate due to actual or
               potential differing interest between the Indemnified Party and
               any other party represented by such counsel in such proceeding.
               No Indemnifying Party, in the defense of any such claim or
               litigation shall, except with the consent of each Indemnified
               Party, consent to entry of any judgment or enter into any
               settlement that does not include as an unconditional term thereof
               the giving of the claimant or plaintiff to such Indemnified Party
               of a release from all liability in respect of such claim or
               litigation, and except in the event that the Indemnifying Party
               has been given notice of a claim but has not assumed the defense
               of the Indemnified Party in which case the Indemnified Party may
               settle such case in its reasonable discretion, no Indemnified
               Party shall consent to entry of any judgment or settle such claim
               or litigation without the prior written consent of the
               Indemnifying Party.

         9.4 TERMINATION. AHPC's incidental registration rights hereunder shall
terminate as to any Shares upon the earlier of (i) seven (7) years after the
Closing Date or (ii) such time as no such Shares are held by AHPC.


     SECTION 10. MISCELLANEOUS.

          10.1 NOTICES. Any consent, notice or report required or permitted to
be given or made under this Agreement by one of the parties hereto to the other
shall be in writing, delivered personally or by facsimile (and promptly
confirmed by telephone, personal delivery or courier) or courier, postage
prepaid (where applicable), addressed to such other party at its address
indicated below, or to such other address as the addressee shall have last
furnished in writing to the addressor and shall be effective upon receipt by the
addressee.

         If to ArQule:                      ArQule, Inc.
                                    200 Boston Avenue, Suite 3600
                                    Medford, MA  02155
                                    Attention:  Eric B. Gordon
                                    Tel:    (617) 395-4100
                                    Fax:    (617) 395-1225


         with a copy to:            Palmer & Dodge LLP
                                    One Beacon Street
                                    Boston, Massachusetts 02108
                                    Attention:  Michael Lytton, Esq.
                                    Tel:    (617) 573-0100
                                    Fax:    (617) 227-4420

                                       11
<PAGE>   15


         If to AHPC:                American Home Products Corporation
                                    Five Giralda Farms
                                    Madison, New Jersey 07940
                                    Attention:  Senior Vice President 
                                    and General Counsel
                                    Tel:    (201) 660-5000
                                    Fax:    (210) 660-7155

          10.2 ENTIRE AGREEMENT. This Agreement contains the entire
understanding of the parties with respect to the subject matter hereof. All
express or implied agreements and understandings, either oral or written,
heretofore made are expressly merged in and made a part of this Agreement.

          10.3 ASSIGNMENT. Neither this Agreement nor any of the rights and
obligations contained herein may be assigned or otherwise transferred by either
party without the consent of the other party; PROVIDED, HOWEVER, that either
ArQule or AHPC may, without such consent, assign its rights and obligations
under this Agreement (i) to any Affiliate, all or substantially all of the
equity interest of which is owned and controlled by such party or its direct or
indirect parent corporation, or (ii) in connection with a merger, consolidation
or sale of substantially all of such party's assets to an unrelated third party;
PROVIDED, HOWEVER, that such party's rights and obligations under this Agreement
shall be assumed by its successor in interest in any such transaction and shall
not be transferred separate from all or substantially all of its other business
assets, including those business assets. Any purported assignment in violation
of the preceding sentence shall be void. Any permitted assignee shall assume all
obligations of its assignor under this Agreement.

          10.4 AMENDMENTS AND WAIVERS. This Agreement may not be modified or
amended except pursuant to an instrument in writing signed by ArQule and AHPC.
The waiver by either party hereto of any right hereunder or the failure to
perform or of a breach by the other party shall not be deemed a waiver of any
other right hereunder or of any other breach or failure by said other party
whether of a similar nature or otherwise.

          10.5 HEADINGS. The headings of the various sections of this Agreement
have been inserted for convenience of reference only and shall not be deemed to
be part of this Agreement.

          10.6 SEVERABILITY. In case any provision contained in this Agreement
should be invalid, illegal or unenforceable in any respect, the validity,
legality and enforceability of the remaining provisions contained herein shall
not in any way be affected or impaired thereby.

          10.7 GOVERNING LAW. This Agreement shall be governed by and construed
in accordance with the laws of the State of Delaware (without giving effect to
the choice of law provisions thereof) and the federal law of the United States
of America.

          10.8 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, each of which shall constitute an original, but all of which, when
taken

                                       12
<PAGE>   16

together, shall constitute but one instrument, and shall become effective when
one or more counterparts have been signed by each party hereto and delivered to
the other parties.

          10.9 EXPENSES. Except as otherwise specifically provided herein, each
party shall bear its own expenses in connection with this Agreement.

          10.10 PUBLICITY. Neither party hereto shall issue any press releases
or otherwise make any public statement with respect to the transactions
contemplated by this Agreement without the prior consent of the other party
which shall not be unreasonably withheld, except as may be required by
applicable law or regulation.

            [The remainder of this page is intentionally left blank]

                                       13

<PAGE>   17




     IN WITNESS WHEREOF, the parties hereto have caused this Common Stock
Purchase Agreement to be executed by their duly authorized representatives as of
the day and year first above written.


ARQULE, INC.



By:  /s/ Eric B. Gordon
     -----------------------------------------
     Eric B. Gordon
     President and Chief Executive Officer


AMERICAN HOME PRODUCTS CORPORATION



By: /s/ Gerald A. Jibilian
   -------------------------------------------

Title: Vice President
      ----------------------------------------


                                       14
<PAGE>   18


                                    EXHIBIT A
                                    ---------
                      Form of Opinion of Palmer & Dodge LLP
                      -------------------------------------

                                      DRAFT

                SUBJECT TO OPINION COMMITTEE REVIEW AND APPROVAL







Telephone: (617) 573-0100                              Facsimile: (617) 227-4420

                               _____________, 1998


Sr. Vice President and General Counsel
American Home Products Corporation
5 Girlada Farms
Madison, NJ  07940

Gentlemen:

     This opinion is furnished to American Home Products Corporation (the
"Purchaser") pursuant to Section 6.3 of the Common Stock Purchase Agreement
dated as of July 3, 1997 (the "Agreement") by and between ArQule, Inc., a
Delaware corporation (the "Company"), and the Purchaser. Capitalized terms used
but not otherwise defined in this opinion shall have the meanings ascribed to
them in the Agreement.

     We have acted as counsel for the Company in connection with the
preparation, execution and delivery of the Transaction Documents (as hereinafter
defined). In so acting, we have examined and relied upon originals or copies of
the following documents:

     (i)   the Agreement;

     (ii)  the Amended and Restated Certificate of Incorporation of the Company
           (the "Amended Certificate");

     (iii) the Amended and Restated By-laws of ArQule (the "By-laws"); and

     (iv)  the Research and License Agreement dated July 3, 1997 between the
           Company and American Home Products Corporation acting through its
           Wyeth-Ayerst Research division (the "Research Agreement").

                                       15
<PAGE>   19

     The Agreement and the Research Agreement are collectively referred to
herein as the "Transaction Documents."

     For purposes of the opinions expressed below, we have examined the
originals or copies of such records, agreements and instruments of the Company,
certificates of public officials and of officers of the Company and such other
documents and records, and such matters of law, as we have deemed appropriate as
a basis for the opinions hereinafter expressed. In making such examination, we
have assumed the genuineness of all signatures, the legal capacity of natural
persons, the authenticity of all documents submitted to us as originals and the
conformity to the originals of all documents submitted to us as copies. As to
various facts material to the opinions set forth herein, we have relied without
independent verification upon factual representations made by the Company in the
Agreement, upon certificates of public officials and upon facts certified to us
by officers of the Company. Our opinion in paragraph 1 below, insofar as it
relates to the legal existence and good standing of the Company, is based solely
upon a certificate of legal existence issued by the Secretary of the State of
Delaware on ______________, 19___. In rendering the opinion in paragraph 7
hereof as to pending actions or proceedings, we have made no independent review
of any court's dockets.

     The opinions expressed herein with respect to the enforceability of the
Agreement are subject to (i) general principles of equity (regardless of whether
such enforcement is considered in a proceeding at law or in equity), including,
without limitation, the discretion of any court of competent jurisdiction in
granting specific performance, injunctive or other equitable relief, and (ii)
bankruptcy, insolvency, reorganization, moratorium or similar laws of general
application affecting the rights and remedies of creditors heretofore or
hereafter enacted to the extent that the same may be constitutionally applied.
Other than as set forth in paragraph 6 below, we express no opinion as to the
effect of or the compliance by the Company with any federal or state securities
laws, or as to the application of any of the foregoing laws to the matters set
forth herein.

     Statements herein qualified by the phrase "to our knowledge" or similar
phrase refer to the actual knowledge of the individual lawyers in our firm who
participated in the negotiation and drafting of the Transaction Documents, based
upon inquiries of the Company's officers and employees with regard to the
Transaction Documents and the transactions contemplated therein as we deemed
appropriate.

     For purposes of the opinions expressed herein, we have assumed that at all
relevant times the Purchaser had all requisite power and authority and had taken
all necessary action to enter into and perform all of their respective
obligations under the Transaction Documents and such other documents, agreements
and instruments to which they are a party, and that each of the Transaction
Documents and such other document, agreement and instrument was and will
continue to be the valid, binding and enforceable obligation of each other party
thereto, other than the Company. You have not asked us to express, and we do not
express, any opinion upon the application of any federal, state or local
statute, law, rule or regulation

                                       16
<PAGE>   20

to the authority of the Purchaser or any party other than the Company to enter
into and to carry out its respective obligations, and exercise its rights, under
the Transaction Documents or such other documents, agreements and instruments.

     This opinion is limited to the laws of the State of Delaware, the
Commonwealth of Massachusetts and the federal laws of the United States of
America and we express no opinions with respect to the law of any other
jurisdiction.

     Based upon and subject to the foregoing we hereby advise you that, in our
opinion, as of the date hereof:

          1. The Company is a corporation duly organized, validly existing and
in good standing under the laws of the State of Delaware, and has the requisite
corporate power and authority to own its properties and to conduct its business
as presently conducted. The Company is qualified to do business and is in good
standing as a foreign corporation in the Commonwealth of Massachusetts and is
not required to be qualified as a foreign corporation to do business in any
other jurisdiction in the United States in which the ownership of its property
or the conduct of its business requires such qualification and where any
statutory fines and penalties or any corporate disability imposed for the
failure to qualify would have a Material Adverse Effect.

          2. The Company has the requisite corporate power and authority to
execute, deliver and perform its obligations under each of the Transaction
Documents. The execution and delivery of each of the Transaction Documents by
the Company and the performance by the Company of its obligations thereunder
have been duly authorized by all corporate action on the part of the Company.
Each of the Transaction Documents has been duly executed and delivered by the
Company and constitutes a valid and binding obligation of the Company,
enforceable against the Company in accordance with its terms.

          3. The authorized capital stock of the Company is as described in
Section 4.2 of the Agreement and, to our knowledge, the other representations
and warranties of the Company contained in Section 4.2 of the Agreement are true
and correct. The rights, and privileges of, and restrictions on, the Common
Stock are as stated in the Amended Certificate.

          4. The issuance, sale and delivery of the shares of Common Stock by
the Company in accordance with the Agreement have been duly authorized by all
necessary corporate action on the part of the Company, and the shares of Common
Stock when so issued, sold and delivered against payment therefor in accordance
with the provisions of the Agreement will be duly and validly issued, fully paid
and non-assessable.

          5. The execution, delivery and performance of each of the Transaction
Documents by the Company, and the issuance of the shares of Common Stock will
not violate the Amended and Restated Certificate of Incorporation or Amended and
Restated By-

                                       17
<PAGE>   21

laws of ArQule [or any ArQule Subsidiary, if any], as the same exist on the date
hereof, or to our knowledge, any provision of any material indenture, mortgage,
agreement, contract or other material instrument to which ArQule [or any ArQule
Subsidiary, if any] is a party or by which any of its properties or assets is
bound as of the date hereof, and to our knowledge, will not require any consent
by any person under, constitute or result (upon notice or lapse of time or both)
in a breach of any term, condition or provision of, or constitute a default or
give rise to any right of termination or acceleration under any such indenture,
mortgage, agreement, contract or other material instrument or result in the
creation or imposition of any material lien, security interest, mortgage,
pledge, charge or other encumbrance upon any properties or assets of ArQule [or
any ArQule Subsidiary, if any]. Upon its execution and delivery, and assuming
the valid execution thereof by AHPC, the Agreement will constitute a valid and
binding obligation of ArQule, enforceable against ArQule in accordance with its
terms, except as enforceability may be limited by applicable bankruptcy,
insolvency, reorganization, moratorium or similar laws affecting creditors' and
contracting parties' rights generally and except as enforceability may be
subject to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law).

          6. Assuming the accuracy of the representations of the Purchaser
expressly contained in the Agreement, the offer, issuance and sale of the shares
of Common Stock pursuant to the terms of the Agreement are exempt from the
registration requirements of Section 5 of the Securities Act of 1933, as
amended, by virtue of Section 4(2) thereof.

          7. Except as otherwise disclosed in writing to the Purchaser, to our
knowledge, there are no actions, proceedings or investigations pending or
threatened against the Company or affecting its properties or assets, which,
either in any case or in the aggregate, could have a Material Adverse Effect.

          8. No consent, approval, order or authorization of, or qualification,
registration, designation, declaration or filing with, any federal or state
governmental authority is required on the part of the Company in connection with
the consummation of the transactions contemplated by the Transaction Documents,
except such filings as may be required under applicable federal and state
securities laws.

     This opinion is furnished to you solely for your benefit in connection with
the Transaction Documents and may not be relied upon by any other person or
entity or for any other purpose without our express, prior written consent.

                                                              Very truly yours,



                                                              PALMER & DODGE LLP

                                       18


<PAGE>   1
                                                                      EXHIBIT 11

                                  ARQULE, INC.



         STATEMENT REGARDING COMPUTATION OF UNAUDITED NET LOSS PER SHARE
                      (IN THOUSANDS, EXCEPT PER SHARE DATA)

<TABLE>
<CAPTION>
                                                      THREE MONTHS             SIX MONTHS
                                                          ENDED                  ENDED
                                                         JUNE 30,               JUNE 30,
                                                      1997      1996         1997      1996
                                                            (Pro Forma)            (Pro Forma)
                                                   --------------------   -------------------- 
<S>                                                <C>         <C>        <C>         <C>     
Net loss (unaudited)                               $   (435)   $  (588)   $   (730)   $  (754)

Weighted average shares outstanding (unaudited):
       Common Stock                                  11,591        523      10,724        528
       Assumed conversion of preferred stock             --      6,209          --      6,209
       Shares issuable pursuant to SAB 83 using
           the treasury stock method                     --        706          --        706
                                                   --------    -------    --------    -------

              Total shares                           11,591      7,438      10,724      7,443

Net loss per share (unaudited)                     $  (0.04)   $ (0.08)   $  (0.07)   $ (0.10)
                                                   ========    =======    ========    =======
</TABLE>


                                      -15-

<TABLE> <S> <C>

<ARTICLE> 5
<MULTIPLIER> 1,000
<CURRENCY> U.S. DOLLARS
       
<S>                             <C>
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-START>                             JAN-01-1997
<PERIOD-END>                               JUN-30-1997
<EXCHANGE-RATE>                                      1
<CASH>                                          12,488
<SECURITIES>                                    40,593
<RECEIVABLES>                                    1,146
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                                54,816
<PP&E>                                          10,193
<DEPRECIATION>                                   2,875
<TOTAL-ASSETS>                                  62,499
<CURRENT-LIABILITIES>                            4,262
<BONDS>                                              0
                                0
                                          0
<COMMON>                                           118
<OTHER-SE>                                      55,624
<TOTAL-LIABILITY-AND-EQUITY>                    62,499
<SALES>                                          6,518
<TOTAL-REVENUES>                                 6,518
<CGS>                                            4,326
<TOTAL-COSTS>                                    8,251
<OTHER-EXPENSES>                                     0
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                                 143
<INCOME-PRETAX>                                  (730)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                              (730)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     (730)
<EPS-PRIMARY>                                   (0.07)
<EPS-DILUTED>                                   (0.07)
        

</TABLE>


© 2022 IncJournal is not affiliated with or endorsed by the U.S. Securities and Exchange Commission