The U.S. Food and Drug Administration (FDA) recently accepted an Investigational New Drug (IND) application for tazemetostat as a potential treatment of mesothelioma in adults. The decision allows Epizyme, the company developing tazemetostat, to soon begin clinical investigations in people with this type of cancer.
The drug is already in Phase 2 clinical studies for specific other cancers.
“We are moving quickly to expand the tazemetostat clinical program into mesothelioma, adding to our ongoing studies in non-Hodgkin lymphoma and certain genetically defined solid tumors,” Robert Bazemore, president and chief executive officer of Epizyme, said in a press release. “We believe that tazemetostat has the potential to treat multiple types of cancer in patients who have limited treatment options. We look forward to starting the mesothelioma phase 2 study later this year.”
Tazemetostat is a small molecule that inhibits the activity of an enzyme called EZH2, whose abnormal activity has been linked to different types of cancers. The new mesothelioma studies of the drug, in people whose disease is characterized by a BAP1 loss of function, is also planned to be a Phase 2 clinical trial.
Mesothelioma development has been associated with BAP1, a protein that normally keeps cell growth under control but seems to lose its function in mesothelioma cases. This loss of BAP1 function induces EZH2-dependent cell proliferation and leads to tumor formation. Inhibiting EZH2 activity, for this reason, may have a positive effect on mesotheliomas linked to BAP1 loss of function.
According to the company, there are around 12,000 new cases of mesothelioma every year in the developed world. Of these, 50–60 percent are linked to BAP1 loss of function.
Epizyme, which specializes in epigenetic (gene regulating) therapies for cancer, also announced plans to initiate additional clinical studies of tazemetostat in 2016, including a combination with R-CHOP in patients with diffuse large B-cell lymphoma, and a combination with an immune checkpoint inhibitor in non-Hodgkin lymphoma patients.