Genmab Reports 45.9% Response Rate for Experimental Treatment for Platinum-Resistant Ovarian Cancer
Key Facts
On October 3, Genmab announced results from Part C of the Phase 1/2 RAINFOL-01 trial, which included 109 patients with platinum-resistant ovarian cancer who received the experimental treatment Rina-S. The confirmed objective response rate was 45.9%, including five complete responses, according to the company statement. Median duration of response reached 12.1 months, while median progression-free survival was 9.5 months. Investigator Elizabeth Lee said, "The antitumor activity and durability of response in this heavily pretreated population are encouraging." The results are a clinical signal from an early-stage study, while the treatment’s efficacy compared with another treatment option is still being tested in a Phase 3 trial.
The company said antitumor activity was seen across different levels of FRα receptor expression, including cases with low or no expression. It said activity was observed regardless of whether patients had previously received mirvetuximab. In an assessment of response durability, 51% of responders remained in response after one year, according to Part C results. The statement also said 53% of patients had received three or four prior lines of treatment, and all patients in the group had previously received bevacizumab and a taxane treatment. These characteristics place the results in the context of a group that had undergone multiple treatments, without changing the fact that the data come from a Phase 1/2 trial.
The results were accompanied by common side effects including nausea in 67.9% of participants and fatigue in 57.8%, according to Genmab’s statement. Treatment-emergent side effects led to discontinuation in 5.5% of participants. The statement presents these figures alongside response and duration measures, providing a picture of clinical activity and tolerability in the study group. The company announcement did not describe Rina-S as an approved treatment, but as a treatment under study. Nor does the announcement establish that a regulatory approval application has been filed or that approval is imminent.
The Phase 3 RAINFOL-02 trial remains the program’s broader comparative test; it compares Rina-S with investigator’s choice of treatment and has progression-free survival as a primary endpoint. The investor presentation says the study includes about 530 patients, enrollment is complete, and data are expected during 2026. On October 6, Investing.com reported Genmab shares rose 7.6% to 2,558 Danish kroner, reaching a 52-week high, and attributed the move to investors reassessing the company’s pipeline after it announced two clinical developments within 48 hours. Separately, EL7 data show GMAB closed at 40 on October 22, without specifying the currency. Phase 3 data were still expected during the fourth quarter of 2026 in coverage published before the news date; therefore, this article does not attribute the October 22 close or share move to a new RAINFOL-02 results announcement.