Auxilium Pharmaceuticals Completes Sale of 3.45 Million Shares of Common Stock Resulting in $115.7 Million in Net Proceeds

MALVERN, PA--(Marketwire - October 01, 2009) - Auxilium Pharmaceuticals, Inc. (NASDAQ: AUXL) announced today that it has closed its previously announced public offering of 3,000,000 shares of its common stock at a price of $34.50 per share. On September 29, 2009, Jefferies & Company, acting as the sole book-running manager of the offering, exercised in full its over-allotment option to purchase an additional 450,000 shares of common stock. The exercise of the option increased the size of the offering to an aggregate of 3,450,000 shares of common stock.

Auxilium received proceeds, net of offering expenses and underwriting discounts and commissions, of approximately $115.7 million. Auxilium offered the shares of its common stock sold in the offering pursuant to a Registration Statement on Form S-3 (Reg. No. 333-133477) filed with the Securities and Exchange Commission on August 27, 2007 and declared effective on September 19, 2007.

Auxilium expects to use the net proceeds from the sale of the shares of its common stock sold in the offering for general corporate purposes, including working capital, product development and capital expenditures.

Copies of the final prospectus supplement and related prospectus may be obtained from Jefferies & Company, Inc., Attention: Syndicate Prospectus Department, 520 Madison Avenue, New York, NY 10022 or at (888) 449-2342.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of, these securities in any state or other jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such state or jurisdiction.

About Auxilium

Auxilium Pharmaceuticals, Inc. is a specialty biopharmaceutical company with a focus on developing and marketing to urologists, endocrinologists, orthopedists and select primary care physicians. Auxilium markets Testim® 1%, a topical testosterone gel, for the treatment of hypogonadism through its approximately 190-person sales and marketing team. Auxilium has five projects in clinical development. XIAFLEX™ (collagenase clostridium histolyticum), formerly referred to as AA4500, has completed phase III clinical trials for the treatment of Dupuytren’s contracture, and the biologics license application is under review at the FDA for the treatment of Dupuytren’s contracture. XIAFLEX is in phase IIb of development for the treatment of Peyronie’s disease and is in phase II of development for treatment of Frozen Shoulder syndrome (Adhesive Capsulitis). Auxilium’s transmucosal film product candidate for the treatment of overactive bladder (AA4010) and its fentanyl pain product using its transmucosal delivery system are in phase I of development. The Company is currently seeking a partner to further develop these product candidates. Auxilium has rights to additional pain products and products for hormone replacement and urologic disease using its transmucosal film delivery system. Auxilium also has options to all indications using XIAFLEX for non-topical formulations.

SAFE HARBOR STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995

This release contains “forward-looking-statements” within the meaning of The Private Securities Litigation Reform Act of 1995, including statements regarding the Company’s use of the net proceeds from the offering and the impact thereof on the Company’s growth; products in development for Peyronie’s disease, Frozen Shoulder syndrome, overactive bladder, pain, hormone replacement and urologic disease; and all other statements containing projections, statements of future performance or expectations, our beliefs or statements of plans or objectives for future operations (including statements of assumption underlying or relating to any of the foregoing). Forward-looking statements can generally be identified by words such as “believe,” “appears,” “may,” “could,” “will,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “expect,” and other words and terms of similar meaning in connection with any discussion of projections, future performance or expectations, beliefs, plans or objectives for future operations (including statements of assumption underlying or relating to any of the foregoing). Actual results may differ materially from those reflected in these forward-looking statements due to various factors, including further evaluation of clinical data, results of clinical trials, decisions by regulatory authorities as to whether and when to approve drug applications, and general financial, economic, regulatory and political conditions affecting the biotechnology and pharmaceutical industries and those discussed in Auxilium’s Annual Report on Form 10-K for the year ended December 31, 2008 and in Auxilium’s Quarterly Report on Form 10-Q for the period ended June 30, 2009 under the heading “Risk Factors,” which are on file with the Securities and Exchange Commission (the “SEC”) and may be accessed electronically by means of the SEC’s home page. There may be additional risks that Auxilium does not presently know or that Auxilium currently believes are immaterial which could also cause actual results to differ from those contained in the forward-looking statements. Given these risks and uncertainties, any or all of these forward-looking statements may prove to be incorrect. Therefore, you should not rely on any such factors or forward-looking statements.

In addition, forward-looking statements provide Auxilium’s expectations, plans or forecasts of future events and views as of the date of this release. Auxilium anticipates that subsequent events and developments will cause Auxilium’s assessments to change. However, while Auxilium may elect to update these forward-looking statements at some point in the future, Auxilium specifically disclaims any obligation to do so. These forward-looking statements should not be relied upon as representing Auxilium’s assessments as of any date subsequent to the date of this release.