ImmunoGen Inc. announced that the US Food and Drug Administration (FDA) has granted accelerated approval for ELAHERE (mirvetuximab soravtansine-gynx) for the treatment of adult patients with folate receptor alpha (FRα)-positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer, who have received one to three prior systemic treatment regimens. ELAHERE was approved under FDA’s accelerated approval program based on objective response rate (ORR) and duration of response (DOR) data from the pivotal SORAYA trial. Continued approval may be contingent upon verification and description of clinical benefit in a confirmatory trial. ELAHERE is a first-in-class ADC directed against FRα, a cell-surface protein highly expressed in ovarian cancer, and is the first FDA approved ADC for platinum-resistant disease.
“The approval of ELAHERE is significant for patients with FRα-positive platinum-resistant ovarian cancer, which is characterized by limited treatment options and poor outcomes,” said Ursula Matulonis, MD, Chief of the Division of Gynecologic Oncology at the Dana-Farber Cancer Institute, Professor of Medicine at the Harvard Medical School, and SORAYA Co-Principal Investigator. “ELAHERE’s impressive anti-tumor activity, durability of response, and overall tolerability observed in SORAYA demonstrate the benefit of this new therapeutic option, and I look forward to treating patients with ELAHERE.”
“With an indication for use regardless of prior treatment with Avastin, we believe ELAHERE is positioned to become the new standard of care for patients with FRα-positive platinum-resistant ovarian cancer,” said Mark Enyedy, ImmunoGen’s President and Chief Executive Officer. “ELAHERE’s accelerated approval is a testament to the decades of work dedicated to developing the next generation of ADCs and marks ImmunoGen’s transition to a fully-integrated oncology company and the start of an exciting new chapter for us as a leader in the development and commercialization of innovative oncology products. With a highly experienced commercial and medical team in place, we are well prepared to support a successful launch and deliver ELAHERE rapidly to patients across the US.”
ELAHERE was evaluated in the pivotal SORAYA trial, a single-arm study in 106 patients with platinum-resistant ovarian cancer whose tumors expressed high levels of FRα and who had been treated with one to three prior systemic treatment regimens – at least one of which included Avastin (bevacizumab). The primary endpoint was confirmed ORR as assessed by investigator and the key secondary endpoint was DOR. Per the label, ELAHERE demonstrated an ORR by investigator of 31.7% (95% confidence interval [CI]: 22.9, 41.6), including five complete responses (CRs). The median DOR was 6.9 months (95% CI: 5.6, 9.7) as assessed by investigator. The safety of ELAHERE has been evaluated in a pooled analysis from three studies among a total of 464 patients with FRα-positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer who received at least one dose of ELAHERE (6 mg/kg adjusted ideal body weight (AIBW) administered intravenously once every 3 weeks).
The prescribing information for ELAHERE includes a boxed warning for ocular toxicity, including visual impairment, keratopathy, dry eye, photophobia, eye pain, and uveitis. The most common adverse reactions (greater than or equal to 20% of patients), including laboratory abnormalities, were vision impairment, fatigue, increased aspartate aminotransferase, nausea, increased alanine aminotransferase, keratopathy, abdominal pain, decreased lymphocytes, peripheral neuropathy, diarrhea, decreased albumin, constipation, increased alkaline phosphatase, dry eye, decreased magnesium, decreased leukocytes, decreased neutrophils, and decreased hemoglobin.
“Platinum-resistant ovarian cancer is a notoriously challenging disease to treat. Given there have been no new therapies approved by FDA for this indication since 2014, ELAHERE’s accelerated approval is a tremendous advance in the ovarian cancer treatment paradigm,” said Anna Berkenblit, MD, Senior Vice President and Chief Medical Officer of ImmunoGen. “We are thrilled with today’s approval and extend our sincere thanks to the patients, families, caregivers, and investigators who helped make this achievement a reality and have supported the broader mirvetuximab development program. As we work to deliver more good days to patients, we look forward to the continued evaluation of mirvetuximab in earlier lines of treatment, in combination, and across a wider range of levels of FRα expression.”
MIRASOL, the confirmatory randomized trial designed to convert the accelerated approval of ELAHERE to full approval, is fully enrolled and top-line data are expected in early 2023. During the Biologics License Application review, FDA requested ImmunoGen submit preliminary ORR and DOR data from both arms of MIRASOL. To maintain data integrity for the ongoing MIRASOL trial, an independent third-party statistician performed the analyses and submitted the outputs directly to FDA.
FDA has also granted approval of the VENTANA FOLR1 (FOLR1-2.1) RxDx Assay, the only companion diagnostic to aid in identifying patients eligible for treatment with ELAHERE, developed by Roche. Approximately 35-40% of ovarian cancer patients express high levels of FRα, which is defined as greater than or equal to 75% tumor cells staining with 2+ intensity. Testing can be done on fresh or archived tissue; newly diagnosed patients can test at diagnosis to determine if ELAHERE will be an option for them at the time of progression to platinum resistance. Testing is now available in the US through four centralized laboratories and is expected to expand to additional laboratories over time.
ImmunoGen is committed to helping eligible platinum-resistant ovarian cancer patients gain access to treatment with ELAHERE and is providing support through our ELAHERE Support Services program.