FDA Grants Full Approval to Mirvetuximab for Platinum-Resistant Ovarian Cancer

Sketch of ovarian cancer - stock.adobe.com

• Mirvetuximab soravtansine-gynx (Elahere) has been fully approved by the FDA for patients with platinum-resistant ovarian cancer with high folate receptor alpha (FR⍺) expression who have received 1 to 3 prior lines of treatment.
• Mirvetuximab was granted accelerated approval in 2022.
• In December 2023, the FDA granted the supplemental biologics license application of mirvetuximab priority review.

The FDA has fully approved mirvetuximab soravtansine, a first-in-class antibody-drug conjugate, for the treatment of platinum-resistant ovarian cancer with high (FR⍺) expression that has received 1 to 3 prior lines of treatment.¹

The approval is supported by findings from the confirmatory phase 3 MIRASOL trial (NCT04209855) of mirvetuximab vs investigator’s choice of chemotherapy in patients with platinum-resistant, advanced epithelial ovarian, primary peritoneal, or fallopian tube cancers with high folate-receptor alpha (FR⍺) expression.²

The median overall survival observed in the study was 16.5 months (95% CI, 14.5-24.6) among patients in the mirvetuximab soravtansine-gynx arm vs 12.7 months (95% CI, 10.9-14.4) in the chemotherapy arm (HR, 0.67; 95% CI, 0.50-0.88; P =.0046). The median progression-free survival in the mirvetuximab arm was 5.6 months (95% CI, 4.3-5.9) and 4.0 months (95% CI, 2.9-4.5) in the chemotherapy arm (HR, 0.65; 95% CI, 0.52-0.81; P <.0001). Further, the overall response rate was 42% (95% CI, 36-49) vs 16% (95% CI, 12-22; P <.0001), in their respective arms.

"As the first treatment to show a statistically significant overall survival benefit in patients with platinum-resistant ovarian cancer, Elahere provides an effective new option for patients with folate receptor alpha positive tumors. These patients previously had very limited options and Elahere changes that," said Kathleen Moore, MD, deputy director and associate director of clinical research at the Stephenson Cancer Center of The University of Oklahoma and MIRASOL principal investigator.³

Regarding safety, the FDA reported that adverse reactions occurring in at least 20% of patients “were increased aspartate aminotransferase, fatigue, increased alanine aminotransferase, blurred vision, nausea, increased alkaline phosphatase, diarrhea, abdominal pain, keratopathy, peripheral neuropathy, musculoskeletal pain, decreased lymphocytes, decreased platelets, decreased magnesium, decreased hemoglobin, dry eye, constipation, decreased leukocytes, vomiting, decreased albumin, decreased appetite, and decreased neutrophils.”¹

The dose of mirvetuximab soravtansine that is recommended is 6 mg/kg adjusted ideal body weight administered once every 3 weeks in a 21-day cycle. The agent is given as an intravenous infusion until disease progression or unacceptable toxicity.

REFERENCES:

1. FDA approves mirvetuximab soravtansine-gynx for FRα positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer. News release. FDA. March 22, 2024. Accessed March 22, 2024. https://tinyurl.com/y67xwybh

2. FDA grants priority review of ImmunoGen’s supplemental biologics license application for Elahere (mirvetuximab soravtansine-gynx) in platinum-resistant ovarian cancer. News release. December 5, 2023. Accessed January 25, 2024. http://tinyurl.com/4fhzeyjw

3. U.S. Food and Drug Administration (FDA) Grants Full Approval for ELAHERE® (mirvetuximab soravtansine-gynx) for Certain Ovarian Cancer Patients. Published online and accessed March 22, 2024. https://tinyurl.com/yc6jexse