ImmunoGen’s ovarian cancer drug misses Phase III primary endpoint

4th March 2019 (Last Updated August 9th, 2019 09:38)

US-based biotechnology company ImmunoGen has reported negative top-line results from the Phase III FORWARD I ovarian cancer trial of mirvetuximab soravtansine.

ImmunoGen’s ovarian cancer drug misses Phase III primary endpoint
IBI188 is a fully human monoclonal antibody designed to target the CD47 antigen on tumour cells. Credit: Penn State/Flickr.

US-based biotechnology company ImmunoGen has reported negative top-line results from the Phase III FORWARD I ovarian cancer trial of mirvetuximab soravtansine.

The study failed to meet its primary endpoint of progression-free survival (PFS). Mirvetuximab soravtansine is an antibody-drug conjugate (ADC) targeting folate receptor alpha (FRα).

The FORWARD I trial assessed the safety and efficacy of the drug compared to chemotherapy in a total of 366 FRα-positive, platinum-resistant ovarian cancer patients.

Its primary endpoint of PFS was assessed in the complete study population and in a subset of patients with high FRα expression, and has been missed in both the cases.

"This study with mirvetuximab did not result in the outcome that we had hoped for in platinum-resistant patients."

The confirmed overall response rate was observed to be higher for mirvetuximab soravtansine than chemotherapy in the entire study population. However, there was no significant difference in overall survival.

Data also showed that fewer patients had grade III or higher adverse events, dose reductions and discontinuations due to drug-related adverse events with mirvetuximab soravtansine compared to chemotherapy.

The safety profile of the drug was also confirmed, with the most common adverse events being nausea, diarrhoea and blurred vision.

ImmunoGen president and CEO Mark Enyedy said: “This study with mirvetuximab did not result in the outcome that we had hoped for in platinum-resistant patients. We will further assess the data from FORWARD I to determine potential next steps with a monotherapy approach.”

The company intends to conduct additional analyses to further study the potential benefit of mirvetuximab soravtansine for FRα-positive platinum-resistant ovarian cancer.

Enyedy added: “In parallel, we have generated encouraging data with mirvetuximab combination regimens and will evaluate our ongoing studies as an independent path forward to support a registration in ovarian cancer.”