PD32-04 PHASE I/II CLINICAL TRIAL TO ASSESS SAFETY AND EFFICACY OF INTRATUMORAL AND SUBCUTANEOUS INJECTION OF HVJ-E TO CASTRATION RESISTANT PROSTATE CANCER PATIENTS

total and free T, sex hormone binding globulin (SHBG), bone turnover markers and hot flashes. RESULTS: The 250 mg cohort (n1⁄439) has completed the time period for assessment of the primary endpoint. Ten of the 39 (26%) subjects exhibited a 50% decrease in PSA by Day 90, with 11/39 (28%) by Day 120, while 18/39 (46%) had PSA declines of 30%. Median SHBG levels increased 301% of baseline, confirming the principal mechanism of drug action. While on study, median free T decreases of 44% were observed across all subjects and 20/26 (77%) of the subjects with baseline serum free T levels >0.7 pg/ml fell below this level. Therefore, 250 mg GTx-758 decreased free testosterone levels in an additive fashion to their existing LHRH therapy. The bone turnover biomarker, C-telopeptide, decreased in 79% of the subjects. 250 mg of GTx-758 has been generally well tolerated with two reported possibly drug related SAEs (VTE and MI). CONCLUSIONS: In this Phase 2 trial, 250 mg daily GTx-758 has activity, likely mediated by lowering free T levels in patients with CRPC on LHRH therapy, and may provide amelioration of estrogen deficiency side effects associated with ADT.