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EXHIBIT 10.15.1
FIRST AMENDMENT TO COLLABORATION AGREEMENT
This First
Amendment to Collaboration Agreement (this "First Amendment")
dated as of December 31, 2004, is by and
between Regeneron Pharmaceuticals,
Inc., a corporation organized and existing
under the laws of the State of New
York and having its principal office at 777
Old Saw Mill River Road, Tarrytown,
New York 10591 ("Regeneron ") and Aventis
Pharmaceuticals Inc., a corporation
organized and existing under the laws of
the State of Delaware and having a
principal place of business at 200 Crossing
Blvd., Bridgewater, New Jersey 08807
("Aventis").
INTRODUCTION
WHEREAS, Regeneron and
Aventis are Parties to a Collaboration Agreement,
having an Effective Date of September 5,
2003 (the "Collaboration Agreement");
and
WHEREAS,
Regeneron and Aventis have determined that it is desirable to
amend and restate certain provisions of the
Collaboration Agreement and document
further agreements between them as set
forth herein.
NOW,
THEREFORE, in consideration of the following mutual promises
and
obligations and for good and valuable
consideration, the receipt and sufficiency
of which are hereby acknowledged, the
Parties, intending to be legally bound,
hereby agree as follows:
Capitalized terms used in this First
Amendment and not defined herein shall have
the meanings ascribed to them in the
Collaboration Agreement.
1. MILESTONE 1. Milestone
1 of Schedule 2 of the Collaboration Agreement is
hereby
amended and restated to read in its entirety as follows:
1 US $25,000,000
[******************************].
2. ENTIRE AGREEMENT;
SUCCESSORS AND ASSIGNS. The Collaboration Agreement,
this First
Amendment, and any written agreements executed by both Parties
pertaining
to the subject matter therein, constitute the entire agreement
between
t
