MALVERN, Pa. and NEW YORK, Jan. 3, 2013 /PRNewswire/ -- Auxilium Pharmaceuticals, Inc. (NASDAQ: AUXL) ("Auxilium") and Xstelos Holdings, Inc. (OTCQB: XTLS) ("Xstelos") today announced that they have received a notice from Upsher-Smith Laboratories, Inc. ("USL") that advises them of USL's filing of a 505(b)(2) New Drug Application (NDA) containing a Paragraph IV certification under 21 U.S.C. Section 314.52(c) for testosterone gel. This Paragraph IV certification notice refers to the ten U.S. patents, covering Testim®, 1% testosterone gel, that are listed in the Approved Drug Products with Therapeutic Equivalence Evaluations (commonly known as the Orange Book), published by the U.S. Food and Drug Administration. These ten patents are owned by FCB I LLC, an indirect majority owned subsidiary of Xstelos. Xstelos holds the assets of CPEX Pharmaceuticals, Inc., the predecessor owner of the patents. The referenced Testim patents will expire between 2023 and 2025. (Logo: http://photos.prnewswire.com/prnh/20101202/MM10881LOGO ) Auxilium and Xstelos are currently reviewing the details of this notice from Upsher Smith. Auxilium and Xstelos intend to pursue all available legal and regulatory options in defense of Testim, including enforcement of their intellectual property rights and approved labeling. About Auxilium Auxilium Pharmaceuticals, Inc. is a specialty biopharmaceutical company with a focus on developing and marketing products to predominantly specialist audiences. Auxilium markets Testim® 1% (testosterone gel) for the topical treatment of hypogonadism and XIAFLEX® (collagenase clostridium histolyticum) for the treatment of adult DC patients with a palpable cord in the U.S. GSK co-promotes Testim with Auxilium in the U.S. Ferring International Center S.A. markets Testim in certain countries of the EU and Paladin Labs Inc. markets Testim in Canada. Pfizer has marketing rights for XIAPEX® (the EU tradename for collagenase clostridium histolyticum) in 46 countries in Eurasia through April 24, 2013; Asahi Kasei Pharma Corporation has development and commercial rights for XIAFLEX in Japan; and Actelion Pharmaceuticals Ltd has development and commercial rights for XIAFLEX in Canada, Australia, Brazil and Mexico. The sBLA for XIAFLEX for the treatment of PD was submitted to the FDA on November 6, 2012 and has been accepted for Standard review with a PDUFA date of September 6, 2013. Additionally, collagenase clostridium histolyticum (CCH) is in phase IIa of development for the treatment of Frozen Shoulder syndrome (adhesive capsulitis) and phase Ib of development for the treatment of cellulite (edematous fibrosclerotic panniculopathy). Auxilium also has rights to pursue additional indications for CCH. For additional information, visit http://www.auxilium.com. About Xstelos Xstelos is a holding company formed for the purpose of holding the assets of CPEX Pharmaceuticals, Inc., an indirect, majority owned subsidiary of Xstelos.