Exhibit 1.1
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JOINT FILING AGREEMENT
The undersigned hereby agree that the Statement on Schedule 13G/A, dated
February 10, 2003 (the "Schedule 13G/A"), with respect to the Common Stock,
$.001 par value, of Enzon Inc. is, and any amendments thereto executed by each
of us shall be, filed on behalf of each of us pursuant to and in accordance with
the provisions of Rule 13d-1(k) under the Securities and Exchange Act of 1934,
as amended, and that this Agreement shall be included as an Exhibit to the
Schedule 13G/A and each such amendment. Each of the undersigned agrees to be
responsible for the timely filing of the Schedule 13G/A and any amendments
thereto, and for the completeness and accuracy of the information concerning
itself contained therein. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument.
IN WITNESS WHEREOF, the undersigned have executed this Agreement as of
the 10th day of February, 2003.
OrbiMed Advisors Inc.
By: /s/ Xxxxxx X. Xxxxx
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Name: Xxxxxx X. Xxxxx
Title: President
OrbiMed Advisors LLC
By: /s/ Xxxxxx X. Xxxxx
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Name: Xxxxxx X. Xxxxx
Title: Managing Member
By: /s/ Xxxxxx X. Xxxxx
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Name: Xxxxxx X. Xxxxx
