Amylin Pharmaceuticals Inc. filed a preliminary prospectus supplement to its shelf registration statement to sell 8.5 million shares that would raise about $141.7 million, based on Friday's closing price.

The San Diego-based company filed the shelf registration in November, allowing it to sell up to $175 million in stock. The company will grant underwriters an overallotment option on up to 1.275 million shares. The company's stock (NASDAQ:AMLN) fell 43 cents Monday to close at $16.24.

In its prospectus supplement, Amylin said it expects to receive about $136.5 million in net proceeds, $157 million if underwriters exercise their overallotment in full, based on a $16.94 assumed offering price. The company would have about 90.4 million shares outstanding after the offering.

As of Sept. 30, Amylin had $180.4 million in cash, cash equivalents and short-term investments. It lost $31.1 million in the third quarter, or 39 cents per share. For the first nine months of the year, it reported a net loss of $80.6 million.

Amylin said it would use the proceeds for research and development, commercialization of Symlin - if approved - and general corporate purposes. Symlin is designed to treat people with diabetes who use insulin. In October 2001, the FDA said Symlin was approvable for marketing as an adjunctive therapy with insulin for the treatment of patients with Type I diabetes and insulin-using patients with Type II diabetes if the company conducted additional clinical trials with satisfactory results. Amylin initiated a seven-month Symlin study - now fully enrolled - focused on safety and involving about 300 patients with Type I diabetes, and it began four smaller studies. The 300-patient study is expected to be completed this quarter. The smaller studies are complete. The company plans to submit a new drug application amendment in this year's first half.

In May 2001, Amylin submitted a marketing approval application for Symlin to European regulatory authorities. In October, Amylin withdrew the application. It said in its prospectus it plans "to engage in further discussion with European regulatory authorities and other regulatory experts to clarify regulatory alternatives and requirements for Symlin." (See BioWorld Today, Oct. 25, 2002.)

Amylin also is developing AC2993, designed to improve glucose control in patients with Type II diabetes who are not achieving target blood glucose concentrations with diet and oral medications. The product entered Phase III trials in December 2001 and Amylin has a total of three trials under way, all of which are fully enrolled and scheduled for completion in the second half of 2003. Amylin signed on Eli Lilly and Co., of Indianapolis, in September to co-develop AC2993 in a deal valued at potentially more than $435 million. (See BioWorld Today, Sept. 23, 2002.)

A sustained-release formulation of AC2993, AC2993 LAR, also is being developed. In June, Amylin began a Phase II trial in the U.S.

Amylin also said in its prospectus it might use a portion of the proceeds to acquire or invest in complementary businesses, products and technologies. In late December, Amylin signed a definitive agreement with Restoragen Inc. to acquire rights to a Phase II program using continuous infusion of glucagon-like peptide 1, targeted for the treatment of congestive heart failure in patients ineligible for transplant. It also acquired rights to various GLP-1-related patents. Through that deal, Restoragen, which filed for Chapter 11 reorganization in December, received $4 million, plus potential milestone payments and royalties.

Goldman, Sachs & Co. is acting as book-running and joint lead manager for the offering. Other joint lead managers are Lehman Brothers, Morgan Stanley and Banc of America Securities LLC. Co-manager of the offering is Fortis Securities Inc.