Exhibit 10.1

 

[Amylin Pharmaceuticals, Inc. letterhead]

 

December 21, 2005

 

Scott Macke

VIA FEDERAL EXPRESS

Senior Product Manager

(IN DUPLICATE)

Mallinckrodt, Inc.

 

675 McDonnell Boulevard

 

St. Louis, Missouri  63134

 

 

Re:                              First Amendment to Exenatide Manufacturing
Agreement dated
October 1, 2003 (the “Agreement”)

 

Dear Mr. Macke:

 

We understand that Amylin Pharmaceuticals, Inc. (“Amylin”) and
Mallinckrodt, Inc. (“Mallinckrodt”) desire to modify the Agreement between
Amylin and Mallinckrodt as stated below for the first time in this amendment
letter. Therefore, Amylin and Mallinckrodt agree as follows:

 

1.                                      The current Section 1.12 is hereby
replaced in its entirety with the following:

 

“Contract Year” variously (as the context requires) means (i) a twelve (12)
month period beginning on October 1, 2003 and ending on September 30, 2004 (i.e.
the “first Contract Year”), (ii) a fifteen (15) month period beginning on
October 1, 2004 and ending on December 31, 2005 (i.e., the “second Contract
Year”) and (iii) thereafter, each consecutive twelve (12) month period
coinciding with the calendar year, beginning with the calendar year 2006 (i.e.
the “third”, “fourth” and all subsequent Contract Years).

 

All provisions of the Agreement (in particular, but without limitation, Sections
2.3, 2.4 and 7.2) will be read and interpreted in a manner consistent with the
amended Section 1.12.

 

Except as expressly amended above, the terms and conditions of the Agreement
will continue in full force and effect in accordance with its terms. The terms
and conditions of this amendment letter will be incorporated into and made a
part of the Agreement effective as of January 1, 2006.

 

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If the terms and conditions of this amendment letter are acceptable, please have
an authorized representative of Mallinckrodt Inc. sign the enclosed duplicate
originals of this amendment letter, and return one fully signed amendment letter
to me for our records.

 

 

Sincerely,

 

 

 

AMYLIN PHARMACEUTICALS, INC.

 

 

 

/s/ Gregg Stetsko

 

 

 

Gregg Stetsko, Ph.D.

 

Vice President, Operations

 

 

Agreed and Accepted:

 

MALLINCKRODT INC.

 

 

By:

/s/ Pat E. Cunningham

 

 

 

 

Name:

 Pat E. Cunningham

 

 

 

 

Title:

V.P. & G.M. API’s Unit

 

 

 

 

Date:

January 6, 2006

 

 

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