<PAGE>
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
SCHEDULE 13G
(RULE 13d-102)
INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT
TO RULES 13d-1(b), (c) AND (d) AND AMENDMENTS THERETO FILED
PURSUANT TO 13d-2(h)
(AMENDMENT NO. )*
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OSI PHARMACEUTICALS, INC.
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(Name of Issuer)
COMMON STOCK
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(Title of Class of Securities)
671040 10 3
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(CUSIP Number)
JUNE 8, 1998
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
/ / Rule 13d-1(b)
/X/ Rule 13d-1(c)
/ / Rule 13d-1(d)
- -----------------------
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which
would alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that
section of the Act but shall be subject to all other provisions of the Act
(however, SEE the NOTES).
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CUSIP NO. 671040 10 3 13G Page 2 of 7 Pages
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(1) Name of Reporting Person:
BIOTECHNOLOGY VALUE FUND, L.P.
I.R.S. Identification No. of above person (entities only).
- -------------------------------------------------------------------------------
(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
- -------------------------------------------------------------------------------
(3) SEC Use Only
- -------------------------------------------------------------------------------
(4) Citizenship or Place of Organization
DELAWARE
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Number (5) Sole Voting Power
of 0
Shares --------------------------------------------------
Beneficially (6) Shared Voting Power
Owned by 662,153
Each --------------------------------------------------
Reporting (7) Sole Dispositive Power
Person 0
With: --------------------------------------------------
(8) Shared Dispositive Power
662,153
- -------------------------------------------------------------------------------
(9) Aggregate Amount Beneficially Owned by Each Reporting Person
662,153
- -------------------------------------------------------------------------------
(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
/ /
- -------------------------------------------------------------------------------
(11) Percent of Class Represented by Amount in Row (9)
3.0%
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(12) Type of Reporting Person (See Instructions)
PN
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 671040 10 3 13G Page 3 of 7 Pages
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(1) Name of Reporting Person:
BVF L.P.
I.R.S. Identification No. of above person (entities only).
- -------------------------------------------------------------------------------
(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
- -------------------------------------------------------------------------------
(3) SEC Use Only
- -------------------------------------------------------------------------------
(4) Citizenship or Place of Organization
DELAWARE
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Number (5) Sole Voting Power
of 0
Shares --------------------------------------------------
Beneficially (6) Shared Voting Power
Owned by 1,367,990
Each --------------------------------------------------
Reporting (7) Sole Dispositive Power
Person 0
With: --------------------------------------------------
(8) Shared Dispositive Power
1,367,990
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,367,990
- -------------------------------------------------------------------------------
(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
/ /
- -------------------------------------------------------------------------------
(11) Percent of Class Represented by Amount in Row (9)
6.1%
- -------------------------------------------------------------------------------
(12) Type of Reporting Person*
PN
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 671040 10 3 13G Page 4 of 7 Pages
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(1) Names of Reporting Person:
BVF INC.
I.R.S. Identification Nos. of above persons (entities only).
- -------------------------------------------------------------------------------
(2) Check the Appropriate Box if a Member (a) /X/
of a Group* (b) / /
- -------------------------------------------------------------------------------
(3) SEC Use Only
- -------------------------------------------------------------------------------
(4) Citizenship or Place of Organization
DELAWARE
- -------------------------------------------------------------------------------
Number (5) Sole Voting Power
of 0
Shares --------------------------------------------------
Beneficially (6) Shared Voting Power
Owned by 1,367,990
Each --------------------------------------------------
Reporting (7) Sole Dispositive Power
Person 0
With: --------------------------------------------------
(8) Shared Dispositive Power
1,367,990
- -------------------------------------------------------------------------------
(9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,367,990
- -------------------------------------------------------------------------------
(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
/ /
- -------------------------------------------------------------------------------
(11) Percent of Class Represented by Amount in Row (9)
6.1%
- -------------------------------------------------------------------------------
(12) Type of Reporting Person*
IA, CO
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* SEE INSTRUCTIONS BEFORE FILLING OUT!
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CUSIP NO. 671040 10 3 13G Page 5 of 7 Pages
ITEM 1. (a) Name of Issuer
OSI Pharmaceuticals, Inc. ("OSI")
ITEM 1. (b) Address of Issuer's Principal Executive Offices
106 Charles Lindbergh Boulevard
Uniondale, NY 11553
ITEM 2. (a) Name of Person Filing
This schedule is being filed on behalf of the following
persons*:
(i) Biotechnology Value Fund, L.P. ("BVF")
(ii) BVF Partners L.P. ("PARTNERS")
(iii) BVF Inc. ("BVF Inc.")
* Attached as Exhibit A is a copy of an agreement among
the persons filing (as specified hereinabove) that this
Schedule 13G is being filed on behalf of each of them.
ITEM 2. (b) Address of Principal Business Office:
The principal business office of the persons comprising the
group filing this Schedule 13G is located at 333 West Wacker Drive, Suite
1600, Chicago, Illinois 60606.
ITEM 2. (c) Citizenship:
BVF: a Delaware limited partnership
Partners: a Delaware limited partnership
BVF Inc.: a Delaware corporation
ITEM 2. (d) Title of Class of Securities:
Common Stock, par value $.01 per share.
ITEM 2. (e) CUSIP Number:
671040 10 3
ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO RULE 13d-1(C) CHECK
THIS BOX /X/
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CUSIP NO. 671040 10 3 13G Page 6 of 7 Pages
ITEM 4. OWNERSHIP:
The information in items 1 and 5 through 11 on the cover pages
(pp. 2-5) on Schedule 13G is hereby incorporated by reference.
ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS:
If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more than
five percent of the class of securities, check the following. / /
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
BVF shares voting and dispositive power over the shares of the
common stock it beneficially owns with Partners. Partners and BVF Inc. share
voting and dispositive power over the shares of the common stock they
beneficially own with, in addition to BVF, certain managed accounts on whose
behalf Partners, as investment manager, purchased such shares. None of the
managed accounts individually owns more than 5% of the common stock of OSI.
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY:
Not applicable.
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP:
Not applicable.
ITEM 9. NOTICE OF DISSOLUTION OF GROUP:
Not applicable.
ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired and are not held for
the purpose of or with the effect of changing or influencing the control of
the issuer of the securities and were not acquired and are not held in
connection with or as a participant in any transaction having that purpose or
effect.
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CUSIP NO. 671040 10 3 13G Page 7 of 7 Pages
After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this statement is true,
complete and correct.
Dated: June 19, 1998
BIOTECHNOLOGY VALUE FUND, L.P.
By: BVF Partners L.P., its general partner
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
BVF PARTNERS L.P.
By: BVF Inc., its general partner
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
BVF INC.
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
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EXHIBIT A
AGREEMENT REGARDING JOINT FILING
--------------------------------
The undersigned, Biotechnology Value Fund, L.P., a Delaware limited
partnership, and BVF Partners L.P., a Delaware limited partnership, and BVF
Inc., a Delaware corporation, hereby agree and acknowledge that the
information required by Schedule 13G, to which this Agreement is attached as
an exhibit, is filed on behalf of each of them. The undersigned further agree
that any amendments or supplements thereto shall also be filed on behalf of
each of them.
Dated: June 19, 1998
BIOTECHNOLOGY VALUE FUND, L.P.
By: BVF Partners L.P., its general partner
By: BVF Inc., its general partner
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
BVF PARTNERS L.P.
By: BVF Inc., its general partner
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
BVF INC.
By: /s/ MARK N. LAMPERT
--------------------------
Mark N. Lampert
President
