Genmab Announces Promising Results for Rina-S in Ovarian Cancer
News related to:Genmab · 2 min read
COPENHAGEN, Denmark; October 3, 2026 - Genmab, a Danish biotechnology company, announced promising results from a Phase 1/2 clinical trial evaluating rinatabart sesutecan (Rina-S®), an investigational folate receptor alpha (FRα)-targeted, topoisomerase I (TOPO1)-inhibitor antibody-drug conjugate (ADC). The trial, known as RAINFOL™-01, demonstrated a clinically meaningful objective response rate (ORR) and durable median duration of response (mDOR) in patients with platinum-resistant ovarian cancer (PROC).
Among 109 treated patients, Rina-S® achieved a confirmed ORR of 45.9% (95% CI: 36.3-55.7), including five complete responses (CRs). The median duration of response (mDOR) was 12.1 months (95% CI: 6.5-15.4), with 51% of responders remaining in response at one year. The findings were presented in a Late-Breaking Oral Session at the International Gynecologic Cancer Society (IGCS) Congress 2026, held in Montreal, Canada.
The study also reported a median progression-free survival (mPFS) of 9.5 months (95% CI: 7.6-11.3). Antitumor activity was observed regardless of FRα expression levels, including in patients with low FRα expression and non-expressors. The trial evaluated Rina-S® 120 mg/m² given every three weeks as monotherapy in patients with platinum-resistant high-grade serous ovarian, primary peritoneal, or fallopian tube cancer. Eligible patients had received one to three prior lines of therapy, with 53% having received three or four prior lines.
More than half of the patients (53%) had received prior bevacizumab and taxane therapy. Additionally, 49.5% had received a prior PARP inhibitor, and 33% had received prior mirvetuximab soravtansine. The median follow-up exceeded one year. The most common treatment-emergent adverse events (TEAEs) included fatigue (57.8%) and low-grade gastrointestinal events such as nausea (67.9%), vomiting (36.7%), constipation (26.6%), decreased appetite (23.9%), and abdominal pain (18.3%). The most frequently reported hematologic TEAEs were anemia (57.8%), neutropenia (57.8%), decreased platelet count (34.9%), and thrombocytopenia (34.9%). Serious adverse events (SAEs) were reported in approximately one-third of participants, and treatment discontinuation due to TEAEs occurred in 5.5% of participants.
No safety signals for ocular toxicity, peripheral neuropathy, interstitial lung disease (ILD), or stomatitis were observed. The late-breaking results add an important layer of evidence to the growing clinical experience with Rina-S® in patients with platinum-resistant ovarian cancer. These findings, including the observed antitumor activity, duration of response, and the first progression-free survival data reported for the program, as well as the manageable tolerability, reinforce the potential of Rina-S®.
Genmab is advancing Rina-S® in a broad clinical development program, including ovarian, endometrial, and other cancers with unmet need. The program includes four Phase 3 trials evaluating Rina-S® in PROC (RAINFOL-02; NCT06619236), recurrent or progressive endometrial cancer (RAINFOL-03; NCT07166094), platinum-sensitive ovarian cancer (PSOC) maintenance therapy (RAINFOL-04; NCT07225270), and second-line PSOC (RAINFOL-07; NCT07564141). Additional studies include the Phase 1/2 RAINFOL-01 trial (NCT05579366) and Phase 2 trials in non-small cell lung cancer (RAINFOL-05; NCT07288177) and advanced gastrointestinal cancers (RAINFOL-09; NCT07539311).