The company has expertise in the development and humanization of tumor-targeting antibodies, having developed specialized cancer-cell killing agents to serve as payloads – to be attached to such antibodies for targeted delivery to tumor cells.

The company's lead product is Elahere (mirvetuximab soravtansine-gynx), which was granted accelerated approval in November 2022 by the US FDA for adult patients with folate receptor alpha (FRα) positive, platinum-resistant epithelial ovarian, fallopian tube, or primary peritoneal cancer, who have received one to three prior systemic treatment regimens.

Immunogen also selectively outlicenses its technology to other companies for use with their engineered antibodies. It has partnerships with Amgen, Bayer, Biotest, Lilly, Novartis, Roche and Sanofi – all of which have clinical and/or preclinical compounds using its technology.