BOSTON, Mass. – The NEJM Evidence has published interim data from the first part of Phase I/II CYPIDES trial evaluating the safety and efficacy of ODM-208 (or MK-5684), an investigational, oral CYP11A1 inhibitor, in heavily pretreated patients with metastatic castration-resistant prostate cancer (mCRPC).
Prostate cancer continues to be regulated by steroid hormones, even in castration-resistant disease. Results from the Phase I/IIa CYPIDES trial suggest that ODM-208 potently inhibits all steroid-hormone biosynthesis with observed antitumor activity in a heavily pretreated mCRPC population, especially in patients with androgen receptor gene (AR) ligand-binding-domain (LBD) mutations.
In Phase I/IIa CYPIDES, a total of 92 previously treated mCRPC patients received 5mg of ODM-208 twice a day with glucocorticoid/mineralocorticoid replacement and ongoing androgen-deprivation therapy. In phase I, 20 out of the total 47 patients had AR LBD mutation. In phase IIa, all 45 patients had AR LBD mutation. A decrease in PSA (prostate-specific antigen) levels of 50% or more occurred in 14/19 (73.7%) patients with AR LBD mutation and 2/23 (8.7%) AR-wild-type patients in phase I, and in 24/45 (53.3%) patients with AR LBD mutation in phase IIa. Median circulating testosterone levels declined from 3.0 ng/dl at baseline to undetectable levels within the first week of ODM-208 treatment in 46/53 (87%) patients. Although well tolerated by most patients, treatment-related adrenal insufficiency was the most common safety finding. Overall 17 (36.2%) of patients in Phase I and 6 (13.3%) of patients in Phase IIa experienced adrenal insufficiency requiring adjustment of hormone replacement therapy and/or additional supplementation, after which the ODM-208 treatment commonly continued.
“These results support the continued importance of hormone-based treatments and potential of ODM-208 in prostate cancer, even in heavily treated patients with advanced disease. Additional data also shows promising improvement in managing the treatment-related adrenal insufficiency. We look forward to having further data from the latter part of the study both in AR LBD positive and negative patients.”, said Professor, M.D., Ph.D. Outi Vaarala, Senior Vice President of Innovative Medicines and Research and Development at Orion.
About ODM-208
ODM-208 (or MK-5684) is an investigational oral, non-steroidal and selective inhibitor of the CYP11A1 enzyme discovered and developed by Orion for the treatment of hormone-dependent cancers, such as prostate cancer. ODM-208 is being developed through a collaboration with MSD (tradename of Merck & Co., Inc. Rahway NJ USA).
Contact
Terhi Ormio, VP, Communications
Orion Corporation
tel. +358 50 966 4646