European Commission Approves Mirvetuximab Soravtansine for FRα+ Platinum-Resistant Ovarian Cancer

Toon Van Gorp, MD

The European Commission has granted marketing authorization to mirvetuximab soravtansine-gynx (Elahere) for the treatment of adult patients with folate receptor–alpha (FRα)-positive, platinum-resistant, high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer who have received between 1 and 3 prior systemic treatments.¹

The authorization was based on data from the global phase 3 MIRASOL trial (NCT04209855), in which treatment with mirvetuximab soravtansine led to a 35% reduction in the risk of disease progression or death and a 33% reduction in the risk of death vs chemotherapy (HR for progression-free survival [PFS], 0.65; 95% CI, 0.52-0.81; P < .0001; HR for overall survival [OS], 0.67; 95% CI, 0.50-0.89; P = .0046).

With this authorization, mirvetuximab soravtansine has become the first and only FRα-directed antibody-drug conjugate to receive approval in the European Union (EU), as well as in Iceland, Liechtenstein, Norway, and Northern Ireland.

“It’s been 10 years since a new treatment for platinum-resistant ovarian cancer was approved in the EU, and now oncologists have an effective, new, targeted treatment option for these patients,” Toon Van Gorp, MD, professor of gynaecological oncology at the University of Leuven in Belgium, said in a news release.

In March 2024, the FDA granted regular approval to mirvetuximab soravtansine for use in the same indication based on the same dataset from MIRASOL.²

MIRASOL is a global, phase 3 open-label, randomized, controlled trial that randomly assigned 453 patients to receive mirvetuximab soravtansine or investigator’s choice of single-agent chemotherapy consisting of either weekly paclitaxel, pegylated liposomal doxorubicin, or topotecan.1 Eligible patients had platinum-resistant, high-grade serous ovarian cancer with tumors expressing high levels of FRα (≥ 75% of cells with ≥ 2+ staining intensity), confirmed with the VENTANA FOLR1 (FOLR1-2.1) RxDx Assay. Patients had previously received 1 to 3 prior lines of therapy.

The primary end point was investigator-assessed PFS. Key secondary end points included objective response rate (ORR) and OS.

Additional efficacy results published in The New England Journal of Medicine revealed that patients treated with mirvetuximab soravtansine experienced a median PFS of 5.62 months (95% CI, 4.34-5.95) vs 3.98 months (95% CI, 2.86-4.47) with chemotherapy (P < .001).3 Moreover, the median OS was 16.46 months (95% CI, 14.46-24.57) vs 12.75 months (95% CI, 10.91-14.36), respectively. The ORR was 42.3% (95% CI, 35.8%-49.0%) in the mirvetuximab soravtansine arm vs 15.9% (95% CI, 11.4%-21.4%) in the chemotherapy arm (odds ratio, 3.81; 95% CI, 2.44-5.94; P < .001). 

“Ovarian cancer can be devastating, taking women away from precious moments with their family, disrupting careers and the many other important contributions that women make to society,” Clara Mackay, chief executive officer of World Ovarian Cancer Coalition, added in the news release.1 “In Europe, ovarian cancer is 3 times more deadly than breast cancer, and having new innovative options allows us to work toward a world where everyone living with ovarian cancer has the best chance of survival and the best quality of life possible, no matter where they live.”

Regarding the agent’s safety profile, the most frequent adverse effects (AEs) were blurred vision, nausea, diarrhea, fatigue, abdominal pain, keratopathy, dry eye, constipation, vomiting, decreased appetite, peripheral neuropathy, headache, asthenia, increased aspartate aminotransferase, and arthralgia. The most common serious AE was pneumonitis. Notably, fewer grade 3 or higher AEs were reported with mirvetuximab soravtansine (41.7%) vs chemotherapy (54.1%), as were fewer serious AEs of any grade (23.9% vs 32.9%) and fewer events leading to discontinuation (9.2% vs 15.9%).³

“The approval of [mirvetuximab soravtansine] by the European Commission provides a much-needed clinically meaningful option for patients who receive the heartbreaking news their ovarian cancer has returned, fearing what’s next in their treatment journey after they’ve developed platinum-resistance,” Roopal Thakkar, MD, executive vice president of research and development and chief scientific officer of AbbVie, concluded in the news release.¹

References

1. AbbVie receives European Commission approval of Elahere (mirvetuximab soravtansine) for the treatment of platinum-resistant ovarian cancer. News release. AbbVie. November 18, 2024. Accessed November 18, 2024. https://news.abbvie.com/2024-11-18-AbbVie-Receives-European-Commission-Approval-of-ELAHERE-R-mirvetuximab-soravtansine-for-the-Treatment-of-Platinum-Resistant-Ovarian-Cancer
2. FDA approves mirvetuximab soravtansine-gynx for FRα positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer. FDA. March 22, 2024. Accessed November 18, 2024. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-mirvetuximab-soravtansine-gynx-fra-positive-platinum-resistant-epithelial-ovarian
3. Moore KN, Angelergues A, Konecny GE, et al. Mirvetuximab soravtansine in FRα-positive, platinum-resistant ovarian cancer. N Engl J Med. 2023;389(23):2162-2174. doi:10.1056/NEJMoa2309169