GTx Announces Phase III Clinical Development of Toremifene 20 mg on Course Following Planned Safety Review

GTx, Inc. (Nasdaq: GTXI), today announced that following a planned safety review, an independent Data Safety Monitoring Board (DSMB) has recommended that the company continue as planned the pivotal Phase III clinical trial evaluating toremifene 20 mg for the prevention of prostate cancer in men with high grade prostatic intraepithelial neoplasia (PIN), a precancerous lesion of the prostate.

The DSMB meets every six months to review unblinded safety data from the toremifene 20 mg Phase III high grade PIN clinical trial. Nearly 1,600 patients with high grade PIN have been enrolled in the three year clinical trial. The primary endpoint of the trial is a reduction in prostate cancer incidence. The trial is being conducted under a Special Protocol Assessment with the United States Food and Drug Administration. The last patient will complete the Phase III high grade PIN clinical trial in the first quarter of 2010.

About GTx

GTx, Inc., headquartered in Memphis, Tenn., is a biopharmaceutical company dedicated to the discovery, development, and commercialization of small molecules that selectively target hormone pathways to prevent and treat cancer, fractures and bone loss, muscle loss and other serious medical conditions. GTX has completed a pivotal Phase III clinical trial evaluating toremifene 80 mg to reduce the risk of fractures and to treat other estrogen deficiency side effects of androgen deprivation therapy, or ADT, in men with prostate cancer. In December 2008, GTx submitted a New Drug Application, or NDA, for toremifene 80 mg to reduce the risk of fractures in men with prostate cancer on ADT, which has been accepted for filing and review by the U.S. Food and Drug Administration, or FDA. The FDA has informed us that it has targeted October 30, 2009 as the Prescription Drug User Fee Act, or PDUFA, date by which it will respond to our toremifene 80 mg NDA. GTx is also developing toremifene 20 mg in an ongoing pivotal Phase III clinical trial for the prevention of prostate cancer in high risk men with high grade prostatic intraepithelial neoplasia. GTx has licensed to Ipsen Developments Limited exclusive rights in the European Union, Switzerland, Norway, Iceland, Lichtenstein, and the Commonwealth of Independent States to develop and commercialize toremifene for all indications which GTx has licensed from Orion Corporation. In December 2007, GTx and Merck & Co., Inc. entered into a collaboration to discover and develop selective androgen receptor modulators, or SARMs, a new class of drugs with the potential to treat chronic sarcopenia, which is the loss of skeletal muscle mass resulting in reduced physical strength and ability to perform activities of daily living and other musculoskeletal wasting or muscle loss conditions, including muscle loss in patients with chronic obstructive pulmonary disease. GTx and Merck are evaluating multiple SARM product candidates, including Ostarine™ (designated by Merck as MK-2866) and MK-0773, for a variety of musculoskeletal wasting indications. GTx is also developing GTx-758, an oral luteinizing hormone inhibitor for the treatment of advanced prostate cancer which is in a Phase I multiple ascending dose clinical trial.

Forward-Looking Information is Subject to Risk and Uncertainty

This press release contains forward-looking statements based upon GTx’s current expectations. Forward-looking statements involve risks and uncertainties. GTx’s actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, the risks that (i) GTx and its collaboration partners will not be able to commercialize their product candidates if clinical trials do not demonstrate safety and efficacy in humans; (ii) GTx may not be able to obtain required regulatory approvals to commercialize product candidates; (iii) clinical trials being conducted by GTx and its collaboration partners may not be completed on schedule, or at all, or may otherwise be suspended or terminated; and (iv) GTx could utilize its available cash resources sooner than it currently expects and may be unable to raise capital when needed, which would force GTx to delay, reduce or eliminate its product development programs or commercialization efforts. You should not place undue reliance on these forward-looking statements, which apply only as of the date of this press release. GTx’s quarterly report on Form 10-Q filed August 10, 2009 contains under the heading, "Risk Factors,” a more comprehensive description of these and other risks to which GTx is subject. GTx expressly disclaims any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements contained herein to reflect any change in its expectations with regard thereto or any change in events, conditions or circumstances on which any such statements are based.