Qwwss333The antibody-drug conjugate (ADC) mirvetuximab soravtansine (Elahere) could become a new standard of care for some patients with ovarian cancer, specifically those whose tumors are folate receptor-alpha (FR-alpha) positive and also platinum-resistant.
It has clinically meaningful antitumor activity, in this population, with a median overall survival of 15 months (SORAYA trial).
The objective response rate (ORR) for the entire cohort was 32.4%.
This response rate compares favorably to those for other single-agent therapies and the response rates were consistent regardless of the number of prior lines of therapy or previous exposure to PARP inhibitors.
More that 90% of ovarian cancer overexpress folate receptor alpha.
Phase III MIRASOL study compared the efficacy of mirvetuximab soravtansine (MIRV), an antibody-drug conjugate targeting folate receptor alpha (FRα), with standard-of-care chemotherapy in platinum-resistant, advanced high-grade epithelial ovarian, primary peritoneal, or fallopian tube cancers expressing high levels of FRα.
A total of 453 patients with platinum-resistant ovarian cancer and high FRα expression were randomized in a 1:1 ratio to receive either MIRV at a dose of 6 mg/kg or investigator’s choice (IC) of chemotherapy (paclitaxel, pegylated liposomal doxorubicin, or topotecan).
MIRV demonstrated statistically significant and clinically meaningful improvement in PFS, ORR, and OS compared to IC chemotherapy, with a differentiated safety profile consisting predominantly of low-grade ocular and gastrointestinal events.
The most common AEs associated with MIRV were predominantly low-grade ocular events (56% vs. 9% for IC, all grades; 14% vs. 0% for IC, Grade 3+), as well as gastrointestinal events (70% vs. 66% for IC, all grades; 13% vs. 15% for IC, Grade 3+).
When compared to IC, MIRV demonstrated lower rates of Grade 3+ treatment-emergent AEs (42% vs. 54%), serious AEs (24% vs. 33%), and discontinuations due to treatment-emergent AEs (9% vs. 16%).
MIRV is the first antibody drug conjugate for ovarian cancer with proven efficacy and is the only FDA-approved biomarker-directed therapy for platinum resistant ovarian cancer (PROC).
These data are practice-changing and position MIRV as a new standard of care for patients with FRα-positive PROC.