ImmunoGen, Inc. recently announced it has earned a milestone payment with Bayer’s initiation of a global Phase 2 clinical trial of anetumab ravtansine (BAY 94-9343) as a potential treatment for mesothelioma. ImmunoGen is a biotechnology company that develops targeted anticancer therapeutics using its antibody-drug conjugate (ADC) technology, and anetumab ravtansine was developed by Bayer using that technology.
Anetumab ravtansine is a fully human IgG1 monoclonal antibody directed against the cell surface glycoprotein mesothelin (a protein that is overexpressed in all mesotheliomas) and conjugated to the maytansinoid DM4, having potential antineoplastic activity.
“We are excited that Bayer has advanced anetumab ravtansine into a clinical study designed to support its registration,” Daniel Junius, ImmunoGen president and CEO, said in a press release. “There is a significant need for new therapies for mesothelioma, and ImmunoGen is committed to transforming the treatment of difficult cancers — both through our own product programs and through partnerships with other companies.”
The global, open-label and randomized Phase 2 study, NCT02610140, will evaluate the efficacy and safety of anetumab ravtansine versus vinorelbine in patients with advanced (stage 4) or metastatic malignant pleural mesothelioma, who are overexpressing mesothelin and whose disease has advanced despite chemotherapy. Its primary endpoint is progression free survival, defined as time from study initiation to disease progression or death, and many of its 77 sites are currently recruiting patients.
Anetumab ravtansine is being developed by Bayer under a 2008 license agreement with ImmunoGen. The agreement granted Bayer exclusive rights over ImmunoGen’s maytansinoid ADC technology to develop anticancer therapies targeting mesothelin. Bayer will develop, register, and commercialize anetumab ravtansine, with ImmunoGen entitled to receive milestone payments of up to $170 million, as well as potential royalties on commercial sales. The exact payment recently announced was not disclosed.
Mesothelioma is a rare form of cancer that develops from cells of the mesothelium, the protective lining that covers many of the internal organs of the body. This deadly disease is diagnosed in close to 3,000 Americans each year. The only established cause of this cancer is exposure to asbestos.
The most common anatomical site for mesothelioma development is the pleura (the outer lining of the lungs and internal chest wall), but it can also arise in other tissues. This cancer can spread throughout a tissue area as an invasion of a large number of smaller masses, unlike other cancers that are characterized by a single, solid tumor mass. Its diffuse nature has important implications for the difficulties found in the cancer’s treatment and complete surgical extraction.