ESSA Pharma presents promising masofaniten data at 2024 ESMO Congress

ESSA Pharma Inc. presented updated clinical data on masofaniten (EPI-7386) in combination with enzalutamide at the 2024 ESMO Congress in Barcelona, Spain, from September 13-17. The Phase 1/2 study showed that the combination therapy was well tolerated, with 88% of patients achieving a significant reduction in PSA levels. The recommended Phase 2 combination doses were established as masofaniten 600 mg twice daily alongside enzalutamide 160 mg once daily. After 15.2 months of follow-up, neither median time to PSA progression nor radiographic progression-free survival had been reached, indicating potential long-term benefits of the treatment. The study involved a randomized, open-label design, focusing on patients with metastatic castration-resistant prostate cancer (mCRPC) who were naive to second-generation anti-androgens. The results demonstrated rapid and durable PSA reductions, regardless of prior chemotherapy status. The ongoing Phase 2 dose expansion study aims to further evaluate the efficacy of this combination therapy across multiple sites in the US, Canada, Australia, and Europe. Adverse events were primarily Grades 1 and 2, with one patient experiencing a Grade 3 rash. Importantly, masofaniten did not affect enzalutamide exposure, allowing for the full recommended dose of enzalutamide to be used. The study's findings suggest that masofaniten could be a promising addition to existing prostate cancer treatments, potentially improving patient outcomes. ESSA Pharma retains all rights to masofaniten worldwide and plans to provide further updates on the study in 2025, reflecting their commitment to advancing treatment options for prostate cancer patients.