Exhibit 99.1

Auxilium Pharmaceuticals, Inc. Announces

Third Quarter 2011 Financial Results and Recent Operational Highlights

-Total Net Revenues of $66.7 Million, up 24% versus Q3 of 2010

-Worldwide XIAFLEX^® Net Revenues of $13.1 Million; Worldwide Testim^® Net Revenues of $53.6 Million

MALVERN, PA, (October 31, 2011) — Auxilium Pharmaceuticals, Inc. (NASDAQ: AUXL), a specialty biopharmaceutical company, today announced financial results and operational highlights for the quarter ended September 30, 2011. For the third quarter of 2011, Auxilium reported net revenues of $66.7 million compared to net revenues of $53.6 million in the third quarter of 2010. The net loss for the third quarter of 2011 was $(4.1) million, or $(0.08) per share, compared to a net loss of $(12.8) million, or $(0.27) per share, reported for the third quarter of 2010.

“We believe that the progress we made in the third quarter of 2011 will drive long term shareholder value. XIAFLEX^® revenues showed sequential growth over the second quarter of 2011, despite a slight decrease in overall Dupuytren’s procedure volumes, and new XIAFLEX data were well received by physicians attending the American Society for Surgery of the Hand meeting. We remain encouraged by the physician and patient success stories and believe that XIAFLEX will become the standard of care for Dupuytren’s contracture,” said Armando Anido, Chief Executive Officer and President of Auxilium. “Testim^® continued to perform well, despite continuing competition in the testosterone replacement market, with prescriptions posting growth over the third quarter of 2010 and over the second quarter 2011.”

Third Quarter and Recent Operational Highlights:

XIAFLEX:

Testim:

Third Quarter 2011 Revenue Details

Auxilium reported the following unaudited net revenues (all amounts in millions of dollars):

Ex-U.S. & contract revenues represent the ongoing amortization of deferred up-front and milestone payment amounts, cumulative catch-up adjustments for milestone payments received during the period, in the case of Testim, sales of products to our partner and, in the case of XIAFLEX, royalties received on product sales by our licensees. For 2011, XIAFLEX revenue recognition methodology records sales of XIAFLEX when units are sold to XIAFLEX distributors. XIAFLEX 2010 revenue recognition methodology recorded sales of XIAFLEX when units are sold from XIAFLEX distributors to physician offices.

Third Quarter 2011 Financial Details

The net loss for the third quarter of 2011 was $(4.1) million, or $(0.08) per share, compared to a net loss of $(12.8) million, or $(0.27) per share, reported for the third quarter of 2010. Net loss for the third quarter of 2011 included total stock-based compensation expense of $3.8 million, compared to $3.5 million for the third quarter of 2010.

Gross margin on net revenues was 79.7% for the quarter ended September 30, 2011 compared to 78.4% for the year-ago quarter. Gross margin reflects the costs of products sold, royalty obligations due to the Company’s licensors, and the amortization of the deferred costs associated with the Pfizer contract. The increase in the gross margin rate is the result of the contribution of high margin XIAFLEX product sales.

Investment in research and development for the quarter ended September 30, 2011 was $14.2 million, compared to $14.4 million for the comparable period in 2010. The slight decrease in expense results from lower costs related to development of a larger scale production process and increased charges related to the phase III XIAFLEX clinical trials for Peyronie’s disease.

Selling, general and administrative expenses totaled $43.3 million for the quarter ended September 30, 2011 compared with $40.3 million for the year-ago quarter. The increase was primarily due to the promotional and training activity in support of the launch of XIAFLEX for Dupuytren’s in the U.S.

As of September 30, 2011, Auxilium had $149.6 million in cash and cash equivalents compared to $151.8 million on June 30, 2011.

Conference Call

Auxilium will hold a conference call today, October 31, 2011 at 10:00 a.m. ET, to discuss third quarter 2011 results and operational highlights. The presentation slides to be used during the call are now available on the “For Investors” section of the Company’s web site under the “Presentations” tab. A question and answer session will follow the presentation. The conference call and the presentation slides will be simultaneously web cast on the “For Investors” section of the Company’s web site under the “Events” tab. The conference call will be archived for future review until January 31, 2012.

About Auxilium

Auxilium Pharmaceuticals, Inc. is a specialty biopharmaceutical company with a focus on developing and marketing products to predominantly specialist audiences, such as urologists,

endocrinologists, certain targeted primary care physicians, hand surgeons, subsets of orthopedic, general, and plastic surgeons who focus on the hand, and rheumatologists. Auxilium markets XIAFLEX® (collagenase clostridium histolyticum) for the treatment of adult Dupuytren’s contracture patients with a palpable cord and Testim® 1%, a testosterone gel, for the topical treatment of hypogonadism in the U.S. Pfizer has marketing rights for XIAPEX® (the EU tradename for collagenase clostridium histolyticum) in Europe and Asahi Kasei Pharma Corporation has development and commercial rights for XIAFLEX in Japan. Ferring International Center S.A. markets Testim in the EU and Paladin Labs Inc. markets Testim in Canada. Auxilium has three projects in clinical development. XIAFLEX is in phase III of development for the treatment of Peyronie’s disease, in phase IIa of development for the treatment of Frozen Shoulder syndrome (Adhesive Capsulitis) and is in phase Ib of development for the treatment of cellulite (edematous fibrosclerotic panniculopathy). Auxilium also has rights to pursue additional indications for XIAFLEX. For additional information, visit http://www.auxilium.com.

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 ability to drive shareholder value; XIAFLEX becoming the standard of care for Dupuytren’s contracture; the phase I study of XIAFLEX for the treatment of cellulite; BioSpecific’s plans to initiate studies of XIAFLEX for the treatment of XIAFLEX for the treatment of canine and human lipomas; the phase IIb trials of XIAFLEX for the treatment of Frozen Shoulder syndrome; the timing of reporting top-line data regarding the phase III program for XIAFLEX for the treatment of Peyronie’s disease; the size of, and timing of top-line results from, the XIAFLEX phase IIIb Dupuytren’s contracture multicord study; the future occurrence or likelihood of additional launches of XIAPEX in other EU and Eurasian markets and our receipt of any applicable milestone payments from Pfizer; the Company’s expected financial performance in 2011; and products in development for Peyronie’s disease, Frozen Shoulder syndrome and cellulite.

Forward-looking statements often address Auxilium’s expected future financial position or business strategy and plans and objectives of management for future operations. Forward-looking statements provide Auxilium’s current expectations or forecasts of future events. Auxilium’s performance and financial results could differ materially from those reflected in these forward-looking statements due to various risks and uncertainties.

A more detailed list and description of the risks and uncertainties that Auxilium faces may be found under the heading “Risk Factors” in Auxilium’s Annual Report on Form 10-K for the year ended December 31, 2010 and Form 10-Q for the quarter ended June 30, 2011, which are on file with the Securities and Exchange Commission. Given these risks and uncertainties, any or all of the forward-looking statements contained in this release may prove to be incorrect. Therefore, you should not rely on any such factors or forward-looking statements. Auxilium undertakes no obligation to update publicly any forward-looking statement.

CONTACT:

James E. Fickenscher

Chief Financial Officer, Auxilium Pharmaceuticals, Inc.

+1-484-321-5900

jfickenscher@auxilium.com

or

William Q. Sargent Jr.

Vice-President, Investor Relations and Corporate Communications

+1-484-321-5900

wsargent@auxilium.com

-Tables to Follow-

AUXILIUM PHARMACEUTICALS, INC.

Condensed Consolidated Statement of Operations

(In thousands, except share and per share amounts)

(Unaudited)