A phase 3, open-label, randomized study of rinatabart sesutecan (Rina-S) vs investigator’s choice (IC) of chemotherapy in patients with platinum-resistant ovarian cancer (PROC).

Background: Ovarian cancer (OC) is the fifth leading cause of cancer-related death among women in the United States, with 12,730 estimated deaths in 2025. In patients (pts) with advanced OC, 70% experience recurrence and many develop platinum-resistant OC (PROC) after standard platinum-based treatment. Rinatabart sesutecan (Rina-S) is an antibody-drug conjugate targeting folate receptor alpha (FRα) with a novel hydrophilic protease-cleavable linker and exatecan, a topoisomerase I inhibitor. In cohort B1 of a phase 1/2 trial (NCT05579366), Rina-S 120 mg/m² every 3 weeks (Q3W) showed encouraging anti-tumor activity with a 50% objective response rate (ORR; 95% CI, 26-74), including 1 complete response, and was well tolerated in a heavily pretreated OC population, with >90% having PROC. Responses were observed regardless of FRα expression status. Here we report the design of an open-label, randomized, phase 3 study (NCT06619236) to investigate Rina-S vs IC chemotherapy in pts with PROC.

Methods: This phase 3 study will enroll ~530 pts with platinum-resistant, high-grade serous or endometrioid epithelial OC, primary peritoneal cancer, or fallopian tube cancer regardless of FRα expression status (Table). Pts will be randomized 1:1 to receive Rina-S 120 mg/m² IV Q3W or IC chemotherapy (paclitaxel, topotecan, pegylated liposomal doxorubicin, or gemcitabine). Primary endpoint is progression-free survival. Secondary endpoints include overall survival, ORR, duration of response, CA-125 response, adverse events, and time to second disease progression. Additional endpoints include QTc changes and overall change from baseline and time to deterioration in Global Health Status/Quality of Life, and patient-reported outcomes. Follow-up visits will occur every 12 weeks for up to ~1 year after the treatment period.
Key study criteria.

Inclusion Criteria

Exclusion Criteria

High-grade serous or endometrioid epithelial OC, primary peritoneal cancer, or fallopian tube cancer

Received 1 to 4 prior lines of therapy, including:

  Platinum chemotherapy

  Bevacizumab

  PARP inhibitor (if applicable)

  MIRV (if eligible)

Platinum-resistant disease defined as:

  Pts who received ≥4 cycles of first-line platinum-based therapy who had a response and then progressed 91-183 days after last dose

  Pts who received 2 to 4 lines of platinum-based therapy and have progressed <183 days after last dose

Primary platinum-refractory disease, defined as

  OC that did not respond to a first-line platinum-containing regimen

  OC that progressed ≤91 days after last dose of a first-line platinum-containing regimen

History of another malignancy ≤3 years or evidence of residual disease

Known active central nervous system metastases or carcinomatous meningitis

Disclaimer

This material on this page is ©2025 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org

Author Details

Angeles Secord

Angeles Secord

Duke Cancer Institute, Durham, NC

Abstract Details

Meeting

2025 ASCO Annual Meeting

Session Type

Poster Session

Session Title

Gynecologic Cancer

Track

Gynecologic Cancer

View More

Abstract Disclosure