Dr Konecny on the FDA Approval of Mirvetuximab Soravtansine for FRα+ Platinum-Resistant Ovarian Cancer

Gottfried E. Konecny, MD, lead clinician, gynecologic oncology, Department of Medicine, the University of California, Los Angeles, discusses the significance of the FDA approval of mirvetuximab soravtansine-gynx (Elahere) for patients with FRα-positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer who have received between 1 and 3 prior treatment regimens.

On March 22, 2024, the FDA granted full approval to mirvetuximab soravtansine for the treatment of this patient population. This regulatory decision was backed by findings from the phase 3 MIRASOL trial (NCT04209855). Mirvetuximab soravtansine is a FRα-directed antibody-drug conjugate (ADC) with a payload of DM4, a potent microtubulin inhibitor, Konecny says.

The trial met its primary end point of PFS benefit with the ADC administered intravenously at 6 mg/kg once every 3 weeks vs investigator’s choice of chemotherapy, typically pegylated liposomal doxorubicin, topotecan, or paclitaxel, Konecny explains. The median progression-free survival (PFS) with the ADC was 5.6 months (95% CI, 4.3-5.9) compared with 4.0 months (95% CI, 2.9-4.5) with chemotherapy (HR, 0.65; 95% CI, 0.52-0.81; P < .0001).

The trial also met its key secondary end points of overall survival (OS) and objective response rate (ORR), Konecny notes. The median OS was 16.5 months (95% CI, 14.5-24.6) with mirvetuximab soravtansine vs 12.7 months (95% CI, 10.9-14.4) with investigator’s choice of chemotherapy (HR, 0.67; 95% CI, 0.50-0.88; P = .0046). Furthermore, the ORR was 42% (95% CI, 36%-49%) with the ADC vs 4.0 16% (95% CI, 12%-22%) with chemotherapy (P < .0001).

These data support the use of mirvetuximab soravtansine as the new standard of care for patients with platinum-resistant ovarian cancer, Konecny concludes.

The prescribing information for mirvetuximab soravtansine contained a Boxed Warning for ocular toxicity, and includes peripheral neuropathy, pneumonitis, and embryo-fetal toxicity.