AbbVie  announced the final analysis of the confirmatory Phase 3 MIRASOL trial evaluating the efficacy and safety of ELAHERE^® (mirvetuximab soravtansine-gynx) in women with folate receptor alpha (FRα)-positive platinum-resistant ovarian cancer (PROC) compared to chemotherapy. At 30.5 months median follow-up, treatment with ELAHERE continued to show significant improvements in progression-free survival (PFS) and overall survival (OS) compared to investigator's choice (IC) chemotherapy. Ovarian cancer patients often present with late-stage disease and are historically first treated with platinum-based chemotherapy, which they may become resistant to and require another therapy, such as ELAHERE. 

"Ovarian cancer can be devastating, and when cancer cells stop responding to chemotherapy patients may feel hopeless about their journey. The data presented today reinforce the importance of ELAHERE as a transformative therapy for patients with limited options," said Svetlana Kobina, MD, PhD, vice president, oncology medical affairs, AbbVie. "We remain steadfast in our commitment to bring forward innovative therapies that improve the lives of patients with difficult-to-treat cancers."

In the United States, ovarian cancer is the leading cause of death from gynecological cancers. Each year, approximately 20,000 women are diagnosed. Unfortunately, most patients develop platinum-resistant disease, which is difficult to treat. In this setting, single-agent chemotherapies are associated with minimal survival benefit while adding significant toxicity burden.

The Phase 3 MIRASOL study included 453 patients with high-grade serous epithelial PROC whose tumors express high levels of FRα and had been treated with up to three prior therapies. Key findings from the 30.5-month median follow-up include:

• ELAHERE treatment achieved superior efficacy versus IC chemotherapy, with a median PFS of 5.59 months versus 3.98 months, representing a 37% reduction in the risk of tumor progression or death (HR 0.63; [95% CI: 0.51, 0.79]) and a higher objective response rate of 41.9% versus 15.9%.
• Superior and clinically meaningful overall survival for patients receiving ELAHERE (median 16.85 months) compared to IC chemotherapy (median 13.34 months), representing a 32% reduction in the risk of death (HR 0.68 [95% CI: 0.54, 0.84]).
• Other endpoints included safety and duration of response (DOR), which were consistent with the primary data analysis at 13.1-months median follow-up.

The most common treatment-emergent adverse events (TEAEs) occurring in at least 20% of patients in the ELAHERE arm were blurred vision, keratopathy, abdominal pain, fatigue, diarrhea, dry eye, constipation, nausea and peripheral neuropathy. Compared with IC chemotherapy, treatment with ELAHERE was overall associated with lower rates of grade ≥3 TEAEs, serious AEs and discontinuations due to AEs.

"The final data showcase the significant improvement in overall survival benefit of treatment with ELAHERE compared to standard of care chemotherapy," said investigator and presenter, Toon Van Gorp, MD, PhD, Professor of Gynecologic Oncology, University of Leuven. "The significant improvements in survival, along with the well-characterized safety profile, reinforce ELAHERE as an emerging standard of care for difficult-to-treat ovarian cancer and warrants further study of this medicine in earlier treatment settings."

A separate analysis from the Phase 3 MIRASOL study evaluating the impact of [ELAHERE] treatment-emergent ocular events on patient-reported health-related quality of life (HRQoL), will be shared during an oral presentation March 17 at the SGO Annual Meeting scientific plenary session.

ELAHERE was granted full approval by the U.S. Food and Drug Administration in March 2024 and was approved by the European Commission in November 2024. Marketing Authorization Applications for ELAHERE are also under review in multiple other countries.