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| Form 3 | U.S. SECURITIES AND EXCHANGE COMMISSION
+--------+ WASHINGTON, D.C. 20549
INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES
Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934,
Section 17(a) of the Public Utility Holding Company Act of 1935 or
Section 30(f) of the Investment Company Act of 1940
(Print or Type Responses)
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1. Name and Address of Reporting Person*
Millennium Pharmaceuticals, Inc.
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(Last) (First) (Middle)
75 Sidney Street
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(Street)
Cambridge, Massachusetts 02139
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(City) (State) (Zip)
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2. Date of Event Requiring Statement (Month/Day/Year) 10/14/99
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3. IRS or Social Security Number of Reporting Person
(Voluntary)
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4. Issuer Name and Ticker or Trading Symbol
LeukoSite, Inc. (LKST)
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5. Relationship of Reporting Person to Issuer (Check all applicable)
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/ / Director / / Officer /X/ 10% Owner / / Other
(give title below) (Specify below)
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6. If Amendment, Date of Original (Month/Day/Year)
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7. Individual or Joint Group Filing (Check Applicable Line)
__X__Form Filed by One Reporting Person
_____Form filed by More than One Reporting Person
TABLE I--NON-DERIVATIVE SECURITIES BENEFICIALLY OWNED
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1. Title 2. Amount of 3. Ownership Form: 4. Nature of
of Securities Bene- Direct (D) or Indirect Bene-
Security ficially Owned Indirect (I) ficial Ownership
(Instr. 4) (Inst. 4) (Instr. 5) (Instr. 5)
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Common Stock, No Securities
$.01 Par Value beneficially owned.
See Attachment.
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Reminder: Report on a separate line for each class of securities beneficially
owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction
5(b)(v)
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FORM 3 (continued)
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TABLE II--DERIVATIVE SECURITIES BENEFICIALLY OWNED
(e.g., puts, calls, warrants, options, convertible securities)
<S> <C> <C> <C> <C> <C>
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1. Title of Derivative 2. Date Exer- 3. Title and Amount of Securities 4.Conversion 5. Ownership 6. Nature of in-
Security (Instr. 4) cisable and Underlying Derivative Security or Form of direct Bene-
Expiration (Instr. 4) Exercise Derivative ficial
Date of Security: Ownership
(Month/Day/ Derivative Direct (D) (Instr. 5)
Year) Security or In-
---------------------------- ------------------ direct (I)
Date Expira- Amount or (Instr. 5)
Exer- tion Title Number of
cisable Date Shares
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</TABLE>
Explanation of Responses:
See Attachment.
**Intentional misstatements or omissions of facts constitute Federal Criminal
Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed.
If space is insufficient, See Instruction 6 for procedure.
Potential persons who are to respond to the collection of information
contained in this form are not required to respond unless the form displays a
currently valid OMB Number.
/s/ Kevin Starr 10/20/99
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Name: Kevin Starr Date
Title: Chief Financial Officer
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Attachment to Form 3
Pursuant to the terms of an Agreement and Plan of Merger (the "Merger
Agreement"), dated October 14, 1999, by and among the Reporting Person, ANM,
Inc., a Delaware corporation ("Sub") and a wholly owned subsidiary of the
Reporting Person, and LeukoSite, Inc., a Delaware corporation ("LeukoSite"),
providing, among other things, for the merger of Sub with and into LeukoSite,
with LeukoSite as the surviving corporation and becoming a wholly owned
subsidiary of the Reporting Person in the merger (the "Merger"), each of
Healthcare Ventures III, L.P., Healthcare Ventures V, L.P., Timothy A.
Springer, Ph.D., Christopher K. Mirabelli, Schroder Ventures International
Life Sciences Fund L.P. 1, Schroder Ventures International Life Sciences Fund
L.P. 2, Schroder Ventures International Life Sciences Trust, Martin Peretz,
M.D., Christopher T. Walsh, Ph.D. and Walter Newman (collectively, the
"Stockholders") has, on October 14, 1999, entered into a voting agreement
with the Reporting Person (collectively, the "Voting Agreements").
Pursuant to the Voting Agreements, each Stockholder has agreed that,
provided that the Merger Agreement has not been previously terminated, it
will vote its shares in favor of approval of the Merger Agreement, the Merger
and every matter that could reasonably be expected to facilitate the Merger
at every meeting of the stockholders of LeukoSite called with respect
thereto, and at every adjournment thereof, and on every action or approval by
written consent of the stockholders of LeukoSite. As required by each of the
Voting Agreements, each Stockholder has executed the Irrevocable Proxy,
attached as Exhibit A to the Voting Agreements, designating Kevin Starr and
John Maraganore, each an executive officer of the Reporting Person, to vote
its shares as to the matters referred to in the Voting Agreements.
Pursuant to the Voting Agreements, each Stockholder has also agreed not
to transfer, sell, exchange, pledge or otherwise dispose of or encumber any
of its shares, or to make any offer or agreement relating thereto, prior to
the earlier of (i) such date and time as the Merger becomes effective and
(ii) such date as the Merger Agreement is terminated.
The consummation of the Merger is subject to approval by LeukoSite's
stockholders and the receipt of certain regulatory approvals, including
expiration of the applicable waiting period under the Hart-Scott-Rodino
Antitrust Improvements Act of 1976, and other customary closing conditions.
On October 14, 1999, the Stockholders beneficially owned 3,269,674
shares of the Common Stock of LeukoSite, which amounted to 22.04% of the
total outstanding shares of Common Stock of LeukoSite.
The Reporting Person may be deemed to be, for purpose of Section 16 of
the Securities and Exchange Act of 1934, as amended, a beneficial owner of
all shares beneficially owned by the Stockholders, provided, however, that
the Reporting Person expressly disclaims any pecuniary interest in such
shares.
Attachment to Form 3
