FDA Grants Accelerated Approval of Novel Ovarian Cancer Therapy

The FDA has granted accelerated approval for ImmunoGen’s Elahere (mirvetuximab soravtansine-gynx) to treat adult patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer. It is indicated for women who have received one to three prior systemic treatment regimens. Elahere is a first-in-class antibody-drug conjugate targeted against folate receptor alpha, a cell-surface protein highly expressed in ovarian cancer, and is the first FDA approved ADC for platinum-resistant disease. About 35% to 40% of ovarian cancer patients express high levels of folate receptor alpha.

The wholesale acquisition cost is $6,220 for one vial, Mark Enyedy, ImmunoGen’s president and chief executive officer, said during a conference call. Patients, he said, typically undergo the use of three to four vials per cycle. This translates to $18,660 to $24,800 per treatment cycle.He said the cycles per patient varies by line of therapy and whether it will be combined with other treatments.

Elahere will shipping with the next few days.

The FDA has also granted approval of the Roche’s Ventana FOLR1 RxDx Assay, a companion diagnostic to aid in identifying patients eligible for treatment with Elahere.

Anna Berkenblit, M.D.

“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,” Anna Berkenblit, M.D., senior vice president and chief medical officer of ImmunoGen, said in a press release.

Elahere was approved based on objective response rate (ORR) and duration of response (DOR) data from the pivotal SORAYA trial, a single-arm study in 106 patients with platinum-resistant ovarian cancer. Enrolled patients had tumors that expressed high levels of FRα and had been treated with one to three prior systemic treatment regimens – at least one of which included Avastin (bevacizumab).

Elahere objective response rate by investigator of 31.7%, including five complete responses. The median duration of response was 6.9 months. Top-line data were announced in November 2021 and full data from the study were presented at the Society of Gynecologic Oncology annual meeting in March 2022.

The safety of Elahere has been evaluated in a pooled analysis from three studies among a total of 464 patients. The label includes a boxed warning for ocular toxicity, including visual impairment, keratopathy, dry eye, photophobia, eye pain, and uveitis.

The most common adverse reactions 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.

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, the FDA requested ImmunoGen submit preliminary ORR and DOR data from both arms of MIRASOL.