Research & Development
ImmunoGen Receives FDA Accelerated Approval of Elahere for the Treatment of Platinum-Resistant Ovarian Cancer
16 November 2022 - - The US Food and Drug Administration has granted accelerated approval for Elahere (mirvetuximab soravtansine-gynx) for the treatment of adult patients with folate receptor alpha -positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer, who have received one to three prior systemic treatment regimens, US-based ImmunoGen Inc. (NASDAQ: IMGN), a specialist in the field of antibody-drug conjugates for the treatment of cancer, said.

Elahere was approved under FDA's accelerated approval program based on objective response rate and duration of response 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.

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.

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 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.

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.

Ovarian cancer is the leading cause of death from gynecological cancers in the US.

Each year, roughly 20,000 patients are diagnosed, and 13,000 patients will die.

Most patients present with late-stage disease and will typically undergo surgery followed by platinum-based chemotherapy.

Unfortunately, the majority of patients eventually develop platinum-resistant disease, which is difficult to treat.

In this setting, standard of care single-agent chemotherapies are associated with low response rates, short durations of response, and significant toxicities.

Elahere (mirvetuximab soravtansine-gynx) is a first-in-class ADC comprising a folate receptor alpha-binding antibody, cleavable linker, and the maytansinoid payload DM4, a potent tubulin inhibitor designed to kill the targeted cancer cells.

Elahere is indicated for the treatment of adult patients with folate receptor-alpha positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer, who have received one to three prior systemic treatment regimens.

Select patients for therapy based on an FDA-approved test.