Genmab's Rina-S Beats Chemo in Ovarian Cancer, Cuts Death Risk 57%

Genmab said on Oct 23 that its experimental drug rinatabart sesutecan, known as Rina-S, beat standard chemotherapy in a phase 3 trial in women with platinum-resistant ovarian cancer. The Danish company reported gains in both progression-free survival and overall survival.

What happened

The RAINFOL-02 trial is a global, randomized, open-label study. It enrolled 582 patients whose cancer had become resistant to platinum chemotherapy. Patients took part whatever their level of folate receptor alpha (FRα), the protein the drug targets. Half received Rina-S and half received the doctor's choice of paclitaxel, topotecan, PLD or gemcitabine.

Genmab reported these topline results:

• Progression-free survival (main goal): a 71% lower risk of the cancer growing or death, with a hazard ratio of 0.29. Genmab gives this for its intent-to-treat population of 584 patients, slightly more than the 582 in its trial description. In the primary analysis set of 492 patients, the reduction was 67%.
• Overall survival (key secondary goal): a hazard ratio of 0.43 in the full population. Scrip reported this as a 57% lower risk of death.
• Safety: the company said the safety profile matched what was already known for the drug, with no new signals.

Rina-S is an antibody-drug conjugate. It links an antibody aimed at FRα to exatecan, a topoisomerase I inhibitor. The drug is not approved anywhere, and Genmab notes its safety and efficacy have not been established.

Why it matters

The study's lead investigator, Angeles Alvarez Secord, a professor at the Duke Cancer Institute, called platinum-resistant disease an urgent unmet need. She said the results set a new benchmark for these patients regardless of FRα expression.

The result also sets up competition. Scrip wrote that the data look competitive against AbbVie's Elahere, the first-in-class FRα antibody-drug conjugate. For Genmab, it was the second of three phase 3 readouts the company expects in the fourth quarter of 2026, according to Scrip.

Rina-S is already in five phase 3 trials. These cover platinum-resistant and platinum-sensitive ovarian cancer, first-line ovarian maintenance and endometrial cancer. Earlier studies are testing it in lung and gastrointestinal cancers.

What it means for people in the industry

These are company-reported topline figures. The full data have not yet been presented. Genmab said it will submit them to a future medical meeting and talk with regulators worldwide about next steps. It did not give a filing date.

Things to watch:

• Genmab's investor update on Oct 28, 2026.
• Any filing plans with the FDA or other regulators.
• Results from the other Rina-S phase 3 trials, which will show how widely the drug could be used.

Genmab, based in Copenhagen, has operations in North America, Europe and Asia Pacific. The company says it has eight approved antibody medicines.

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Sources

• Genmab Announces Rinatabart Sesutecan (Rina-S®) Demonstrates Statistically Significant Improvement in Progression-Free Survival and Overall Survival in Patients with Platinum-Resistant Ovarian Cancer, Genmab
• Genmab’s Rina-S Succeeds In First Phase III Trial, Another Win For Late-Stage Portfolio, Scrip