UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

Current Report

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): May 15, 2012

AMYLIN PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

9360 Towne Centre Drive

San Diego, California 92121

(Address of principal executive offices and zip code)

Registrant’s telephone number, including area code: (858) 552-2200

Check the appropriate box below if the Form 8–K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

Item 5.02. Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

On May 15, 2012, the stockholders of Amylin Pharmaceuticals, Inc., or Amylin, voted to approve an amendment to Amylin’s 2009 Equity Incentive Plan, or 2009 EIP, to increase by 12,000,000 shares the aggregate number of shares of Amylin’s common stock authorized for issuance under the 2009 EIP. Amylin stockholders also voted to approve an amendment to Amylin’s 2001 Employee Stock Purchase Plan, or 2001 ESPP, to increase by 2,000,000 shares the aggregate number of shares of Amylin’s common stock authorized for issuance under the 2001 ESPP. The amended and restated 2009 EIP and 2001 ESPP are attached hereto as Exhibits 99.1 and 99.2, respectively, and are incorporated herein by reference.

Item 5.07 Submission of Matters to a Vote of Security Holders

Amylin held its 2012 Annual Meeting of Stockholders on May 15, 2012. At the Annual Meeting, Amylin stockholders voted upon and (i) elected Adrian Adams, Teresa Beck, M. Kathleen Behrens, Daniel M. Bradbury, Paulo F. Costa, Alexander J. Denner, Karin Eastham, James R. Gavin III, M.D., Ph.D., Jay S. Skyler, M.D., MACP and Joseph P. Sullivan to serve as a director of Amylin until the next annual meeting or until his/her successor is elected; (ii) approved an increase of 12,000,000 shares in the aggregate number of shares of Amylin common stock authorized for issuance under the 2009 EIP; (iii) approved an increase of 2,000,000 shares in the aggregate numbers of shares of Amylin common stock reserved for issuance under the 2001 ESPP; (iv) ratified the selection of Ernst & Young LLP as Amylin’s independent registered public accounting firm for the fiscal year ending December 31, 2012; and (v) approved on an advisory basis, the compensation of Amylin’s Named Executive Officers as disclosed in Amylin’s Proxy Statement for the 2012 Annual Meeting of Stockholders.

Amylin had 161,656,477 shares of common stock outstanding and entitled to vote as of March 27, 2012, the record date for the Annual Meeting. At the Annual Meeting, 126,934,085 shares of common stock were present in person or represented by proxy for the five proposals indicated above. The following sets forth detailed information regarding the results of the voting at the Annual Meeting:

Proposal 1: Election of Directors.

Proposal 2: Approval of an increase of 12,000,000 shares in the aggregate number of shares of Amylin common stock authorized for issuance under the 2009 EIP.

Proposal 3: Approval of an increase of 2,000,000 shares in the aggregate number of shares of Amylin common stock authorized for issuance under the 2001 ESPP.

Proposal 4: Ratification of selection of Ernst & Young LLP as Amylin’s independent registered public accounting firm.

Proposal 5: Approval on an advisory basis, of the compensation of Amylin’s Named Executive Officers as disclosed in Amylin’s Proxy Statement for the 2012 Annual Meeting of Stockholders.

Item 9.01. Financial Statements and Exhibits.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

EXHIBIT INDEX