GTx Announces Enrollment of First Patient in Phase 2 Clinical Trial of Enobosarm in Triple Negative Breast Cancer

GTx, Inc. (Nasdaq: GTXI) today announced the enrollment of the first patientinto its Phase 2 clinical trial of enobosarm (GTx-024) to treat women withadvanced, androgen receptor positive (AR+), triple negative breast cancer(TNBC). Enobosarm is the Company's lead product candidate and is also beingevaluated in a separate Phase 2 clinical trial to treat estrogen receptorpositive (ER+), AR+ breast cancer, which the Company recently announced hadalso enrolled its first patient. "Most women with triple negative breast cancer have extremely limitedtreatment options and poor prognoses," said Robert J. Wills, Ph.D.,Executive Chairman of GTx. "Based on our preclinical research and positivedata from patient-derived and cell line-derived xenografts of TNBC, we arehopeful that enobosarm, by targeting the androgen receptor, may offeranother treatment option to women with this disease." The open-label, multi-center, multinational Phase 2 clinical trial(NCT02368691) will evaluate the efficacy and safety of orally administeredenobosarm in up to 55 women with advanced, AR+ TNBC. Patients will receive18 mg of enobosarm once daily for up to 12 months. The initial stage will beassessed among the first 21 evaluable patients. If at least 2 of 21 patientsachieve clinical benefit at week 16, then the trial will proceed to thesecond stage of enrollment of up to a total of 41 evaluable patients.Clinical benefit is defined as a complete response, partial response, orstable disease, as measured by Response Evaluation Criteria in Solid Tumors(RECIST) at 16 weeks. The trial, which is being conducted under theleadership of Dr. Hope Rugo from the University of California at SanFrancisco, will include investigators from more than 40 clinical trial sitesin the U.S. and abroad.