SECOND AMENDMENT TO THE COMMERCIAL SUPPLY AGREEMENT

EXHIBIT 10.45

***Text Omitted and Filed Separately

with the Securities and Exchange Commission.

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Under 17 C.F.R. Sections 200.80(b)(4)

and 240.24b-2.

SECOND AMENDMENT TO THE

COMMERCIAL SUPPLY AGREEMENT

This Second Amendment to the Commercial Supply Agreement dated February 14, 2005 (this “Second Amendment”), is effective as of January 1, 2012 (the “Second Amendment Effective Date”) by and between Baxter Pharmaceutical Solutions LLC (“BAXTER”), a Delaware limited liability company having a place of business at 927 S. Curry Pike, Bloomington, IN 47403 and Amylin Pharmaceuticals, Inc., (“AMYLIN”) a Delaware corporation having its principal place of business at 9360 Towne Centre Drive, San Diego, California 92121.

WITNESSETH:

WHEREAS, BAXTER and AMYLIN entered into a certain Commercial Supply Agreement dated February 14, 2005 (the “Original Agreement”), as amended by that certain Amendment, dated December 8, 2008 (the “First Amendment”), pursuant to which BAXTER agreed to provide certain services to AMYLIN. The Original Agreement and the First Amendment are hereby collectively referred to herein as the “Agreement”.

WHEREAS, AMYLIN and BAXTER desire to amend the Agreement as set forth below.

NOW THEREFORE, in consideration of the mutual covenants and agreements contained herein, the receipt and sufficiency of which hereby are acknowledged, AMYLIN and BAXTER agree as follows:

In the event AMYLIN submits a Purchase Order for commercial Product and (i) no Production will have occurred for […***…] immediately preceding the date BAXTER is scheduled to commence Production pursuant to such Purchase Order, (ii) such lack of Production is solely attributable to the timing of Purchase Order placement by AMYLIN and (iii) BAXTER was fully capable of Production during such […***…], BAXTER will schedule a non cGMP demo batch prior to Producing the commercial Product pursuant to such Purchase Order and

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AMYLIN will pay to BAXTER […***…] for such demo batch. For clarity, this demo batch will consist of approximately […***…] water-filled units in the same dose configuration as the commercial Batch to be Produced.

Annual Order Increases. In any calendar year during the Term of this Agreement, in no event shall BAXTER be obligated to Produce more than […***…] Units of Product.

“For greater clarity, all Product purchased with a Delivery Date in a certain calendar year, as set forth in the “Firm Purchase Order” for such Product, shall be counted toward Amylin’s Annual Obligation for that certain calendar year. For example, if a “Firm Purchase Order” states a Delivery Date of December 31 2011, the Units of such Product will count toward the 2011 Annual Obligation, regardless of Amylin’s actual release, delivery or shipment of the Product.”

“The Purchase Price will be [...***...] as specified in Exhibit B hereto. Notwithstanding the foregoing, in the event AMYLIN requests any changes to the Production process of a particular Presentation of Product, BAXTER may, as mutually agreed upon by the parties, (i) charge AMYLIN for the costs that are mutually agreed upon in writing by BAXTER and AMYLIN associated with making such Production process changes or (ii) adjust the Purchase Price for such Presentation of Product by revising Exhibit B hereto pursuant to an amendment to this Agreement in accordance with the terms of Article 28 hereto.”

“[RESERVED]”

Invoice Date + […***…] days

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Any payment due under this Agreement not received within the times noted above shall bear interest at the lesser of (a) the maximum rate permitted by law, or (b) […***…]% per month on the outstanding balance compounded […***…].

“This Agreement shall be effective on the Effective Date and shall continue through December 31, 2013 (the “Term”), unless earlier terminated in accordance with the terms of this Agreement.”

Purchase Price

During the Term of this Agreement, BAXTER shall charge AMYLIN the following [...***...] Purchase Price for Product pursuant to Article 5:

[…***…]/Unit

IN WITNESS WHEREOF, the parties hereto have executed this Second Amendment as of the Second Amendment Effective Date written above.

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Exhibit F-1 – Annual Obligation

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