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As filed with the Securities and Exchange Commission on August 30, 2005

Registration No. 333-            

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

AMYLIN PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of incorporation or organization) 33-0266089
(I.R.S. Employer Identification No.)

9360 Towne Centre Drive, Suite 110
San Diego, California 92121
Tel: (858) 552-2200
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Ginger L. Graham
President and Chief Executive Officer
Amylin Pharmaceuticals, Inc.
9360 Towne Centre Drive, Suite 110
San Diego, California 92121
Tel: (858) 552-2200
Fax: (858) 552-2212
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Lloyd A. Rowland
Vice President and General Counsel
Amylin Pharmaceuticals, Inc.
9360 Towne Centre Drive, Suite 110
San Diego, California 92121
Tel: (858) 552-2200
Fax: (858) 552-1936 Thomas A. Coll, Esq.
Cooley Godward LLP
4401 Eastgate Mall
San Diego, California 92121-9109
Tel: (858) 550-6000
Fax: (858) 550-6420

Approximate date of commencement of proposed sale to the public:
As soon as practicable after the effective date of this Registration Statement.

        If the only securities being registered on this form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

        If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

        If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ý 333-111086

        If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

        If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. o

CALCULATION OF REGISTRATION FEE

Title of Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price(1)	Amount of Registration Fee(2)
Common Stock, par value $.001 per share, including related rights to purchase Series A Junior Participating Preferred Stock(3)	—	—
Preferred Stock, par value $.001 per share(3)	—	—
Depositary Shares(4)	—	—
Warrants(5)	—	—
Debt Securities(6)	—	—
Stock Purchase Contracts(7)	—	—
Stock Purchase Units(7)	—	—
Total	$19,520,000(8)	$2,297.51

(1)

The proposed maximum aggregate offering price per class of security will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered hereunder and is not specified as to each class of security pursuant to General Instruction II.D. of Form S-3 under the Securities Act.

(2)

Calculated pursuant to rule 457(o) under the Securities Act.

(3)

Subject to note 8 below, there is being registered hereunder an indeterminate number of shares of common stock and preferred stock of the registrant as may be sold from time to time by the registrant. Pursuant to Rule 416 under the Securities Act, the shares being registered hereunder include such indeterminate number of shares of common stock and preferred stock as may be issuable with respect to the shares being registered hereunder as a result of stock splits, stock dividends or similar transactions. Pursuant to Rule 457(i) under the Securities Act, the shares being registered hereunder include such indeterminate number of shares of common stock and preferred stock as may be issuable upon conversion or exchange of any preferred stock, depositary shares, warrants or debt securities issued under this registration statement. The shares being registered hereunder also include such indeterminate number of shares of common stock and preferred stock as may be issuable upon settlement of stock purchase contracts or stock purchase units.

(4)

Subject to note 8 below, there is being registered hereunder an indeterminate number of depositary shares of the registrant as may be sold from time to time by the registrant. Such depositary shares will be evidenced by depositary receipts issued pursuant to a deposit agreement. Pursuant to Rule 457(i) under the Securities Act, the depositary shares being registered hereunder include such indeterminate number of depositary shares as may be issuable upon conversion or exchange of any preferred stock, depositary shares, warrants or debt securities issued under this registration statement. The depositary shares being registered hereunder also include such indeterminate number of depositary shares as may be issuable upon settlement of stock purchase contracts or stock purchase units.

(5)

Subject to note 8 below, there is being registered hereunder an indeterminate number of warrants to purchase common stock, preferred stock, depositary shares or debt securities of one or more series. Pursuant to Rule 457(i) under the Securities Act, the warrants being registered hereunder include such indeterminate number of warrants as may be issuable upon conversion or exchange of any preferred stock, depositary shares or debt securities issued under this registration statement.

(6)

Subject to note 8 below, there is being registered hereunder an indeterminate principal amount of debt securities of the registrant as may be sold from time to time by the registrant. If any debt securities are issued at an original issue discount, then the offering price shall be in such greater principal amount at maturity as shall result in aggregate gross proceeds to the registrant not to exceed $19,520,000, less the gross proceeds attributable to any securities previously issued pursuant to this registration statement. Pursuant to Rule 457(i) under the Securities Act, the debt securities being registered hereunder include such indeterminate principal amount of debt securities as may be issuable upon conversion or exchange of warrants issued under this registration statement.

(7)

Each stock purchase unit consists of (i) a stock purchase contract, under which the holder, upon settlement, shall purchase from us or sell to us an indeterminate number of shares of common stock or preferred stock or an indeterminate number of depositary shares and (ii) any combination of debt securities, common stock, other stock purchase contracts and debt obligations of third parties, including U.S. Treasury securities.

(8)

In no event will the aggregate offering price of all securities issued from time to time pursuant to this registration statement exceed $19,520,000, excluding accrued interest, if any, on any debt securities issued under this registration statement. The securities registered hereunder may be sold separately or as units with other securities registered hereunder.

EXPLANATORY NOTE

        This registration statement is being filed to register an additional $19,520,000 worth of shares of our common stock and preferred stock, depositary shares, various series of debt securities, warrants to purchase any of such securities, stock purchase contracts and stock purchase units, pursuant to Rule 462(b) of the Securities Act of 1933, as amended. In accordance with Rule 462(b), this registration statement incorporates by reference the contents of our registration statement on Form S-3 (File No. 333-111086) which was declared effective on February 12, 2004, including all amendments, supplements and exhibits thereto and all information incorporated by reference therein, other than the exhibits included herein.

        The required opinions and consents are listed on the Exhibit Index attached to and filed with this registration statement.

SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the Registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San Diego, State of California, on August 29, 2005.

AMYLIN PHARMACEUTICALS, INC.
By:	/s/  MARK G. FOLETTA Mark G. Foletta Vice President, Finance and Chief Financial Officer

        Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

Signature		Date
By:	/s/                * Ginger L. Graham, President, Chief Executive Officer and Director (principal executive officer)	August 29, 2005
By:	/s/ Mark G. Foletta Mark G. Foletta, Vice President, Finance and Chief Financial Officer (principal financial and accounting officer)	August 29, 2005
By:	/s/                * Joseph C. Cook, Chairman of the Board	August 29, 2005
By:	/s/                * Vaughn D. Bryson, Director	August 29, 2005
By:	/s/                * Howard E. Greene, Jr., Director	August 29, 2005
By:	/s/                * Terrance H. Gregg, Ph.D., Director	August 29, 2005
By:	/s/                * Jay S. Skyler, M.D., Director	August 29, 2005
By:	/s/                * Joseph P. Sullivan, Director	August 29, 2005
By:	/s/                * Thomas R. Testman, Director	August 29, 2005
By:	/s/                * James N. Wilson, Director	August 29, 2005
*By:	/s/ Mark G. Foletta Mark G. Foletta Attorney-in-fact

INDEX TO EXHIBITS

Exhibit Number	Description of Document
5.1	Opinion of Cooley Godward LLP.
23.1	Consent of Cooley Godward LLP (included as Exhibit 5.1 to this filing).
23.2	Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm
24.1	Power of Attorney(1)

(1)

Previously filed on the signature page to Registrant's registration statement on Form S-3 (No. 333-111086), filed with the SEC on December 11, 2003.

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EXPLANATORY NOTE
SIGNATURES
INDEX TO EXHIBITS