Results from a phase 1 dose-escalation study evaluating mirvetuximab soravtansine (IMGN853) in patients with folate receptor alpha (FRα)-positive solid tumours were published in the journal Cancer.

The previously disclosed data demonstrated encouraging clinical activity and a manageable safety profile for mirvetuximab soravtansine (IMGN853), and informed the dose that was used in phase 1 expansion cohorts and the ongoing Phase 3 FORWARD I trial of patients with platinum-resistant ovarian cancer.

“These Phase 1 results have played an important role in determining the appropriate dose for mirvetuximab soravtansine in the recently initiated Phase 3 FORWARD I trial of patients with platinum-resistant ovarian cancer,” said Kathleen Moore, M.D., Associate Professor, Department of Obstetrics and Gynecology at the Stephenson Cancer Center at the University of Oklahoma. “The combination of these data and the recent data published in the Journal of Clinical Oncology further support the dose that has been chosen and patients who have been selected for FORWARD I.”

Mirvetuximab soravtansine (IMGN853) is the first FRα-targeting ADC.

It uses a FRα-binding antibody to target the ADC specifically to FRα-expressing cancer cells and a potent anti-tumour agent, DM4, to kill the targeted cancer cells.

Mirvetuximab soravtansine is also being assessed in combination regimens for both platinum-resistant and platinum-sensitive disease in Phase 1b/2 FORWARD II trial.

The open-label, Phase 1 dose-escalation study treated a total of 44 patients with recurrent ovarian (52%) or endometrial cancer (25%), along with renal cell carcinoma and non-small cell lung cancer (11% and 9%, respectively).

Patients received mirvetuximab soravtansine on day 1 of a 21-day cycle (Q3W dosing) with cycles repeated until dose-limited toxicity or progression, concluding the recommended dose for future trials is 6.0 mg/kg of mirvetuximab (based on adjusted ideal body weight) dosed once every three weeks.

On the basis of the study findings, and additional data that demonstrated the importance of FRα expression levels for optimal mirvetuximab sorvatansine activity, the Company designed the Phase 3 FORWARD I trial utilizing this dose in patients with platinum-resistant ovarian cancer, along with a Phase 1b trial evaluating mirvetuximab in combination with standard-of-care chemotherapy and targeted agents.

Mirvetuximab soravtansine exhibited a manageable safety profile and encouraging preliminary clinical activity.

Adverse events (AEs) were generally mild with the majority being grade 1 or grade 2 (least severe grades).

The most commonly observed AEs were fatigue, blurred vision and diarrhoea.

Source: BusinessWire