Mirvetuximab Soravtansine-gynx Granted Full FDA Approval for FRα+ Platinum-Resistant Ovarian Cancer

Mirvetuximab soravtansine-gynx (Elahere; AbbVie) received full FDA approval for the treatment of folate receptor alpha–positive (FRα+), platinum-resistant ovarian cancer (PROC) following 1 to 3 prior lines of therapy, AbbVie announced in a press release.¹

Mirvetuximab soravtansine, an FRα–directed antibody and microtubule inhibitor conjugate, was granted accelerated FDA approval in November 2022 based on results from the SOYAYA study (Study 0417),² with the conversion to a full approval supported by findings from the confirmatory phase 3 MIRASOL trial (NCT04209855).¹

FDA approval stamp | Image credit: Olivier Le Moal - stock.adobe.com

In the randomized, phase 3 MIRASOL trial, 453 patients with FRα+ PROC received either mirvetuximab soravtansine (n = 227) or investigator's choice single-agent chemotherapy (n = 226).³ The main end point was progression-free survival, which was longer in the mirvetuximab soravtansine cohort (5.62 months [95% CI, 4.34-5.95]) compared with the chemotherapy cohort (3.98 months [95% CI, 2.86-4.47]).

Patients in the mirvetuximab soravtansine cohort also experienced significantly longer median overall survival at 16.46 months (95% CI, 14.46-24.57), compared with 12.75 months (95% CI, 10.91-14.36) in the chemotherapy group (HR, 0.67; 95% CI, 0.50-0.89; P = .005).

"As the first treatment to show a statistically significant overall survival benefit in patients with platinum-resistant ovarian cancer, [mirvetuximab soravtansine] provides an effective new option for patients with folate receptor alpha positive tumors," Kathleen Moore, deputy director and associate director of clinical research at the Stephenson Cancer Center of The University of Oklahoma and MIRASOL principal investigator, said in a statement.¹ "These patients previously had very limited options and [mirvetuximab soravtansine] changes that."

Another key secondary end point was investigator-assessed objective response, which was significantly higher in the mirvetuximab soravtansine group (42.3% [95% CI, 35.8%-49.0%]) vs the chemotherapy group (15.9% [95% CI, 11.4%-21.4%]), which translates to an OR of 3.81 (95% CI, 2.44-5.94; P < .001). Of those who responded to mirvetuximab soravtansine, 5.3% (n = 12) experienced complete response and 37% (n = 84) had a partial response. Among responders in the chemotherapy group, no patients experienced complete response, and 15.9% (n = 36) experienced complete responses.

The incidence of grade 3 or higher adverse events was lower with mirvetuximab soravtansine vs chemotherapy, as was the incidence of discontinuation due to adverse events. The most common 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.

References

1. U.S. Food and Drug Administration (FDA) grants full approval for Elahere (mirvetuximab soravtansine-gynx) for certain ovarian cancer patients. News release. AbbVie. March 22, 2024. Accessed March 22, 2024. https://www.prnewswire.com/news-releases/us-food-and-drug-administration-fda-grants-full-approval-for-elahere-mirvetuximab-soravtansine-gynx-for-certain-ovarian-cancer-patients-302097362.html

2. Joszt L. FDA approves mirvetuximab soravtansine-gynx for platinum-resistant ovarian cancer. AJMC. November 15, 2022. Accessed March 22, 2024. https://www.ajmc.com/view/fda-approves-mirvetuximab-soravtansine-gynx-for-platinum-resistant-ovarian-cancer

3. Moore KN, Angelergues A, Konecny GE, et al. Mirvetuximab soravtansine in FRα-positive, patinum-resistant ovarian cancer. N Engl J Med. 2023;389(23):2162-2174. doi:10.1056/NEJMoa2309169