Dr. Moore on Safety Profile of Mirvetuximab Soravtansine in Ovarian Cancer

Kathleen Moore, MD, director of the Oklahoma TSET Phase I Clinical Trials Program; associate professor in the Section of Gynecologic Oncology; Jim and Christy Everest Endowed Chair in Cancer Research; director of the Gynecologic Oncology Fellowship Program; associate director of Clinical Research; and medical director of the Clinical Trials Office, at Stephenson Cancer Center, discusses the safety profile of mirvetuximab soravtansine, an antibody-drug conjugate (ADC) that targets the FRα transmembrane protein, in ovarian cancer.

No advanced toxicity was seen with mirvetuximab soravtansine because, when potent chemotherapy molecules are conjugated to the ADC, the combination is not active until the target is found, explains Moore. To become active, chemotherapy molecules need to be released from the conjugate and they have to be internalized into the tumor cell. Due to the fact that the chemotherapy molecule remains dormant until put in contact with the tumor cell, less chemotherapy is required compared with what you would need if systemic paclitaxel or any of the other agents that flow throughout the body were used, says Moore. Additionally, far less is used in the nanomolar range of cytotoxics with ADCs because the molecules are sent directly into the tumor cell, adds Moore.

Off-target and on-target toxicities still exist with mirvetuximab soravtansine; however, less events are observed compared with what is reported with traditional cytotoxic chemotherapy and toxicities appear to be differentiated, meaning they are not overlapping, according to Moore. As such, mirvetuximab soravtansine fits in well with the treatment options that are otherwise available for patients with ovarian cancer, concludes Moore.