A novel antibody drug conjugate therapy whose clinical trial testing has been co-led by Ursula Matulonis, MD, of the Dana-Farber Cancer Institute has been granted accelerated approval by the U.S. Food and Drug Administration (FDA) on November 14 for the treatment of recurrent platinum-resistant high-grade serous ovarian cancer that highly expresses folate receptor alpha. The approval supports mirvetuximab soravtansine, as a new biomarker-driven standard of care for patients with this form of recurrent ovarian cancer.
Today's FDA action was based on the results of SORAYA study co-led by Matulonis and reported at the Society for Gynecologic Oncology annual meeting in March 2022 as well as at the American Society of Clinical Oncology meeting in June 2022. The trial enrolled 106 patients with platinum-resistant high-grade serous ovarian cancer that highly expressed folate receptor alpha. All participants had received prior bevacizumab and up to three prior treatments for their cancer.
In the study, mirvetuximab soravtansine demonstrated clinically meaningful antitumor activity in patients with platinum resistant ovarian cancer. Mirvetuximab soravtansine generated a confirmed objective response rate - a measurable decrease in cancer burden - in nearly 33% of trial participants. The median duration of response was 6.9 months, and there were 5 patients who experienced a complete response to treatment. Mirvetuximab was well-tolerated by study participants. The most common adverse side effects associated with the treatment were blurred vision, keratopathy (changes to the cornea of the eye based on eye exam), and nausea.
"This accelerated approval of mirvetuximab soravtansine for recurrent, platinum resistant, folate receptor alpha positive ovarian cancer is incredibly meaningful for patients who have this cancer," Ursula A. Matulonis, MD chief of the Division of Gynecologic Oncology and the Brock-Wilson Family Chair at Dana-Farber. "There have been no approved therapies for platinum resistant ovarian cancer since 2014, so today's action by the FDA is a very significant milestone."
The novel agent is one of a growing number of antibody-drug conjugates, or ADCs, which consist of a drug linked to an antibody that directly targets the cancer cell. Mirvetuximab is comprised of an antibody targeting the folate receptor alpha molecule that is physically linked to the drug called DM4 which disrupts microtubule formation. (Microtubules are major components of the cytoskeleton that give shape and structure to cells.) The folate receptor protein is far more abundant in some tumor cells than normal cells, making it an attractive target for cancer drugs.
