Genmab Says Rina-S Meets Both Survival Goals in Phase 3 Ovarian Cancer Trial
Key Facts
Genmab announced positive results on October 23 from the Phase 3 RAINFOL-02 trial of its investigational drug Rina-S in women with platinum-resistant ovarian cancer. The company’s announcement summary said the trial met both its goals of improving progression-free survival and overall survival. The summary described the improvement as statistically significant and clinically meaningful compared with investigator’s choice chemotherapy. The announcement marks an advanced result in the drug’s development program, which had previously shown activity in a smaller Phase 1/2 study. The available summary did not include detailed results from the Phase 3 trial or estimates of the magnitude of improvement.
Earlier data published by Genmab on October 3 came from the RAINFOL-01 study and included 109 patients treated with the drug. The confirmed objective response rate was 45.9%, including 5 complete responses. Median duration of response also reached 12.1 months, and 51% of responders remained in response after a year. The study recorded median progression-free survival of 9.5 months. These results belong to the Phase 1/2 study and provide earlier context for the program, while the October 23 announcement concerns the comparative Phase 3 trial.
The company said antitumor activity in RAINFOL-01 was observed regardless of folate receptor alpha expression level and prior treatment with mirvetuximab. On safety, 5.5% of participants discontinued treatment because of treatment-emergent adverse events. The company observed no safety signals for ocular toxicity, peripheral neuropathy, interstitial lung disease or stomatitis. Serious adverse events were also reported in about one-third of participants in the published group. These figures remain tied to the earlier study, and the Phase 3 announcement summary does not provide comparable safety details.
Rina-S is an investigational antibody-drug conjugate that targets folate receptor alpha and carries exatecan, a topoisomerase 1 inhibitor. The randomized, open-label RAINFOL-02 design compares the drug with investigator’s choice treatment in women with platinum-resistant ovarian cancer. According to the study registry, all participants receive active treatment and there is no placebo group. This comparison helps place the survival result against treatment options selected by investigators, but the available summary does not provide details of those options, participant numbers or efficacy measures.
Genmab said in October that the Rina-S program spans four Phase 3 trials. In addition to RAINFOL-02 for platinum-resistant ovarian cancer, the program includes recurrent or advanced endometrial cancer, maintenance treatment for platinum-sensitive ovarian cancer, and second-line treatment for platinum-sensitive disease. This breadth places the current trial results within a wider development program across multiple gynecologic tumors. But the announcement of a successful trial does not itself establish regulatory approval, and the available source does not include a specific next-step timeline or details on filing applications for approval.
In the market, Genmab shares, listed under the ticker GMAB, closed at 40 dollars on October 22, 2026, according to EL7 data. No session high or low figures are available in the data provided. The closing price also predates the company’s October 23 announcement, so it does not describe a market reaction to the new results. The company had published RAINFOL-01 data on October 3, about three weeks before announcing the Phase 3 results.