(ChemotherapyAdvisor) – AEZS-108 was well tolerated and demonstrated early evidence of antitumor activity in men with castration- and taxane-resistant prostate cancer, results of a Phase 1 study presented at the 2012 Genitourinary Cancers Symposium has found.
AEZS-108, or zoptarelin doxorubicin, is a luteinizing hormone-releasing hormone (LHRH)-cytotoxic hybrid that couples an LHRH agonist and the cytotoxic doxorubicin.
Jacek Pinski, MD, PhD, of the Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA, and colleagues reported on 13 patients treated with AEZS-108 at three dose levels: 3 at 160mg/m2, 3 at 210mg/m2, and 7 at 267mg/m2 administered intravenously over 2 hours every 3 weeks for up to 6 cycles. Two dose-limiting toxicities, asymptomatic grade 4 neutropenia, occurred at the 267mg/m2 dose level; both patients recovered fully. Grade 3 and 4 toxicities were primarily hematology; nonhematologic toxicities were fatigue and alopecia.
Six of 13 (46%) treated patients have received at least 5 cycles of therapy with no evidence of disease progression at 12 weeks; 1 patient received 8 cycles at 210mg/m2 due to continued benefit. Among 5 evaluable patients with measurable disease, 4 achieved stable disease. A decrease in PSA was noted in 6 patients. After an 3 additional patients complete the 210mg/m2 dose level, the Phase 2 portion will commence.
The 2012 Genitourinary Cancers Symposium is sponsored by the American Society of Clinical Oncology, American Society for Radiation Oncology, and the Society of Urologic Oncology.
AEZS-108, being developed by AEterna Zentaris Inc., Québec City, Quebec, Canada, has completed Phase 2 studies in endometrial and ovarian cancer, and is in Phase 2 trials in prostate and bladder cancer. AEZS-108 has been granted orphan-drug designation by the FDA for the treatment of ovarian cancer.