Genmab A/S reported results from Part C of the Phase 1/2 RAINFOL™-01 trial showing that investigational antibody-drug conjugate rinatabart sesutecan, or Rina-S®, produced a confirmed objective response rate of 45.9% among 109 patients with platinum-resistant ovarian cancer. Responses included five complete responses, with a median duration of response of 12.1 months and 51% of responders remaining in response at one year. Median progression-free survival was 9.5 months. Antitumor activity was observed across folate receptor alpha expression levels, including low-expression tumors and non-expressors, and regardless of prior mirvetuximab treatment. The findings were presented at the International Gynecologic Cancer Society Congress 2026 in Montreal. Rina-S was generally manageable in the study, with fatigue, gastrointestinal events, anemia and neutropenia among the most common treatment-emergent adverse events; treatment discontinuation because of such events occurred in 5.5% of participants. Genmab is advancing Rina-S across a broader development program that includes four Phase 3 trials in ovarian and endometrial cancer, alongside studies in lung and gastrointestinal cancers.