Rinatabart Sesutecan for Patients With Platinum-Resistant Ovarian Cancer: First Efficacy and Safety Results From the Phase 2 Cohort of the RAINFOL-01 Study

Elizabeth K. Lee, MD, of Dana-Farber Cancer Institute in Boston, Massachusetts, presents the first efficacy and safety results from the phase 2 cohort of RAINFOL-01, a single-arm study of rinatabart sesutecan, a folate receptor alpha (FRα)-directed antibody-drug conjugate with a topoisomerase 1 inhibitor payload, in 109 patients with platinum-resistant ovarian cancer (PROC). Lee notes that enrollment was not restricted by FRα expression, making this the largest study to date in an unselected PROC population. Patients had received a median of 3 prior lines of therapy, and one-third had received prior mirvetuximab soravtansine. Rinatabart sesutecan 120 mg/m² every 3 weeks produced a confirmed objective response rate of 45.9%, a median duration of response of 12.1 months, a median progression-free survival of 9.5 months, and a 12-month overall survival rate of 66.6%, with responses seen across FRα expression levels. Grade 3 to 4 treatment-emergent adverse events occurred in 66% of patients, with no fatal events and discontinuation in 5.5%.