KEY TAKEAWAYS
- The MIRASOL phase 3 trial aimed to present safety and efficacy data in patients with dose modifications receiving MIRV for high-grade serous PROC.
- The primary efficacy endpoint was PFS.
- The results revealed MIRV’s superior PFS, OS, and ORR, supporting it as the standard for FRα positive PROC.
Mirvetuximab soravtansine (MIRV), an antibody-drug conjugate targeting folate receptor alpha (FRα), has shown improved progression-free survival (PFS), overall response rate (ORR), and overall survival (OS) in patients with high-grade serous platinum-resistant ovarian cancer (PROC) compared to investigator’s choice chemotherapy (ICC), according to Moore K et al. in the New England Journal of Medicine (2023; 389: 2162-74).
Susana Banerjee and the team aimed to present safety and efficacy data in patients who received dose modifications, defined as dose delays, reductions, or interruptions.
About 453 patients with high FRα expression (VENTANA FOLR1 [FOLR1-2.1] RxDx Assay) and 1-3 prior therapies were randomized 1:1 to receive either MIRV 6 mg/kg (adjusted ideal body weight) on Day 1 of a 21-day cycle or ICC, which included paclitaxel, pegylated liposomal doxorubicin, or topotecan. The primary efficacy endpoint was PFS assessed by investigators. Key secondary endpoints included ORR, OS, and patient-reported outcomes in a hierarchical order. Other endpoints included safety, tolerability, and duration of response.
As of the data cutoff on March 6, 2023, 124 patients (57%) in the MIRV arm and 114 patients (55%) in the ICC arm received dose modifications. The median age was 63 for the MIRV arm and 64 for the ICC arm.
In the MIRV arm, 36% had prior bevacizumab compared to 45% in the ICC arm, and 55% had prior PARPi compared to 59% in the ICC arm. The PFS HR was 0.58 (0.43, 0.78), and the OS HR was 0.45 (0.30, 0.69), both favoring MIRV. The ORR was 59.7% for MIRV versus 26.3% for ICC.
Compared to ICC, patients on MIRV had lower rates of grade 3+ treatment-emergent adverse events (TEAEs) (53% vs. 72%) and serious AEs (24% vs. 39%). Treatment discontinuations occurred in 12 patients (10%) on the MIRV arm versus 25 patients (22%) on the ICC arm. Ocular, gastrointestinal, and neurosensory adverse events were comparable to the intent-to-treat population in the respective treatment arms.
The study concluded that dose modifications occurred at similar rates in both treatment arms. MIRV demonstrated longer PFS, OS, and a higher ORR compared to ICC in patients with dose modifications. The efficacy data and well-characterized safety profile support MIRV as the standard of care for patients with FRα positive PROC.
The trial is sponsored by the ImmunoGen, Inc.
Source: https://cslide.ctimeetingtech.com/gynae24hybrid/attendee/confcal/show/session/21
Clinical Trial: https://clinicaltrials.gov/study/NCT04209855
Banerjee S, Van Gorp T, Konecny GE, et al. (2024). “Safety and efficacy results in patients who received dose modifications in the phase III MIRASOL (GOG 3045/ENGOT-ov55) trial of mirvetuximab soravtansine vs investigator’s choice chemotherapy (ICC) in platinum-resistant ovarian cancer (PROC) with high folate receptor-alpha expression.” Presented at ESMO GC 2024. (440)
