Dr. Moore on Early-Phase Data With Mirvetuximab Soravtansine in Ovarian Cancer

Kathleen Moore, MD, director of the Oklahoma TSET Phase I Clinical Trials Program, and 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 early phase data that led to the development of the phase III FORWARD I/ GOG 3011 trial in ovarian cancer.

The initial data that was published on mirvetuximab soravtansine comes from an extensive phase I experience, says Moore. Investigators initially allowed treatment in very heavily pretreated patients and saw efficacy in that group. Investigators then used those findings to target and narrow down the patient population who had received 1 to 3 prior lines of therapy and who had medium to high folate receptor α expression.

In early, phase I trials, the response rates observed with the agent were around 40%, and those response proved to be durable in patients with platinum-resistant disease. Those data led to the development of FORWARD-I/ GOG 3011 as a registration trial to be conducted in a similar population, explains Moore.

Investigators also learned from that fairly large, phase I experience what the expected toxicities would be with mirvetuximab soravtansine. Not too many hematologic toxicities were observed with the agent, and some gastrointestinal (GI) toxicities were expected, according to Moore; however, these events were easily managed. A class effect for many antibody-drug conjugates is visual disturbances, and mirvetuximab soravtansine is no exception, says Moore.

Investigators worked hard to develop mitigation strategies to prevent these AEs from occurring, but if they did occur, they ensured they were low grade and 100% reversible, explains Moore. This work provided a better understanding of the agent and allowed for investigators to move the drug forward for use in a more generalized population in the phase III study, concludes Moore.