A new drug designed to treat recurrent malignant mesothelioma while minimizing side effects has failed to meet expectations.
Anetumab ravtansine, is an antibody-drug conjugate (ADC) developed with biotechnology firms ImmunoGen and MorphoSys and owned by Bayer.
It had been the focus of a Phase II clinical trial for pleural mesothelioma. The trial has now been stopped.
Many of the most dangerous side effects of standard mesothelioma chemotherapy are caused by the destruction of normal cells along with cancer cells.
ADCs like anetumab ravtansine are supposed to help get around the problem by delivering potent cancer-fighters specifically to tumor cells. They combine a cancer-fighting medication with an antibody that targets a protein overproduced by the cancer cells. In the case of mesothelioma tumors (and several other cancers), the targeted protein is mesothelin.
But this week, MorphoSys announced that the Phase II trial of anetumab ravtansine as a second-line treatment for pleural mesothelioma patients “did not meet the primary endpoint”, which was to slow the progression of the disease better than the drug vinorelbine.
A Disappointment for Mesothelioma Sufferers
The trial of anetumab ravtansine was of particular importance for sufferers of malignant pleural mesothelioma, since the disease rarely responds to standard chemotherapy, even at the maximum tolerable dose.
“The outcome of this phase 2 study with anetumab ravtansine in recurrent malignant pleural mesothelioma is disappointing, in particular for the patients suffering from this serious and extremely difficult to treat disease”, said Dr. Markus Enzelberger, Interim Chief Scientific Officer for MorphoSys.
The anetumab ravtansine trial involved multiple cancer centers and 248 people with advanced or metastatic malignant pleural mesothelioma. All patients had undergone standard chemotherapy with Alimta and/or a platinum drug like cisplatin but their tumors had continued to grow.
Patients in the trial received either an infusion of anetumab ravtansine every three weeks or a weekly dose of vinorelbine.
Although Bayer has not yet released detailed study results, the company is expected to do so at an upcoming medical meeting. In the meantime, Bayer is continuing to test anetumab ravtansine in other types of cancer.
Anetumab ravtansine and other ADCs are in pivotal clinical trials for hard-to-treat solid tumors including platinum-resistant ovarian cancer, triple-negative breast cancer, glioblastoma, and small cell lung cancer.
“MorphoSys Announces That Its Partner Bayer Reports On Phase 2 Study of Investigational Anetumab Ravtansine in Second-Line Mesothelioma”, July 21, 2017, MorphoSys website