Dana-Farber Expert Explains Rina-S Data in Platinum-Resistant Ovarian Cancer

Patients with platinum-resistant ovarian cancer who received the investigational treatment rinatabart sesutecan (Rina-S) had a median progression-free survival of 9.5 months, according to findings from the phase 2 cohort of the phase 1/2 RAINFOL-01 trial presented at the International Gynecologic Cancer Society (IGCS) Congress 2026 in Montreal. Progression-free survival measures how long patients lived before their cancer grew or spread.

Platinum-resistant ovarian cancer no longer responds to platinum-based chemotherapy, which makes it difficult to treat. Rina-S is an antibody-drug conjugate (ADC), a type of treatment that uses an antibody to carry a cancer-killing drug to cancer cells. The antibody in Rina-S targets a protein called folate receptor alpha (FRα).

In an interview with CURE, Dr. Elizabeth K. Lee, a study investigator and medical oncologist in the gynecologic oncology program at Dana-Farber Cancer Institute, explained that how a treatment affects daily life matters as much as how well it works.

“Whenever we’re thinking about cancer therapies, whether that is with a standard chemotherapy that might be FDA approved or a clinical trial drug, we really want to make sure that patient safety, the tolerability of a drug and quality of life is always kept top of mind as well,” Lee said. “Because at the end of the day, this is meant to treat real people in the real world and in clinic.”

In the full video interview, Lee walks through what the RAINFOL-01 results could mean for patients with platinum-resistant ovarian cancer. It covers:

• What is Rina-S, and how does it work in ovarian cancer?
• What side effects can patients expect with Rina-S?
• How are low blood counts managed during Rina-S treatment?
• How well does Rina-S work in platinum-resistant ovarian cancer?
• When should patients with ovarian cancer ask about clinical trials?
• Can Rina-S work if a tumor has low or no folate receptor alpha?
• What’s next for platinum-resistant ovarian cancer treatment?

WATCH MORE: Rina-S Shows 45.9% Response Rate in Platinum-Resistant Ovarian Cancer

Among 109 patients, 45.9% had a confirmed objective response, meaning their tumors shrank or disappeared. These included five complete responses, in which no signs of cancer could be detected.

Responses were seen across FRα levels, including in patients whose tumors had low or no FRα expression. They were also seen regardless of whether patients had previously received Elahere (mirvetuximab soravtansine), another FRα-targeted treatment.

Patients in the trial received Rina-S monotherapy every three weeks. More than half (53%) had received three or four prior lines of therapy.

Rina-S is being studied in four phase 3 trials, including RAINFOL-02 in platinum-resistant ovarian cancer. Its safety and efficacy have not been established.

Lee noted that the objective response rate can be hard for patients to understand. Trials follow specific rules about how much a tumor has to shrink to count as a response, and those rules aren’t used in everyday care. In the full video, she explains which measure she finds easier to share with patients in the clinic. She also describes how long responses to Rina-S lasted and why patients whose tumors have little or no FRα may still benefit.

Lee also encourages patients to think about clinical trials earlier in their care than many might expect.

“I would encourage folks really to ask about clinical trials, to really consider clinical trials as early as they feel comfortable doing so in their course of treatment, because these can be really good options,” Lee said.

Reference

1. “Genmab Announces Rinatabart Sesutecan (Rina-S) Phase 2 RAINFOL-01 Results Demonstrated Durable and Clinically Meaningful Responses in Patients with Platinum-Resistant Ovarian Cancer.” News release. Genmab. Posted: Oct. 3, 2026.

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