New Mesothelioma Drug Kills Cancer Stem Cells

Citing “significant enthusiasm within the mesothelioma community”, the manufacturers of a promising new mesothelioma drug say they have begun a major test of the drug in patients.

Massachusetts-based Verastem, Inc. focuses on drugs that fight cancer by attacking the stem cells that give rise to them. Earlier this summer, the FDA granted orphan drug status to their stem cell inhibitor, defactinib, for the treatment of mesothelioma. The designation, which is reserved for drugs that fight the rarest of diseases, helps pave the way for testing and faster approval, depending on the results of clinical trials.

“Development of a drug that preferentially kills cancer stem cells is a promising approach, as many standard-of-care treatments have been shown to either have no effect on, or actually enrich the population of, these chemoresistant cells,” observed Verastem’s Chief Medical Officer, Dr. Joanna Horobin, in a company news release.

The new trial, called COMMAND  (Control of Mesothelioma with Maintenance Defactinib) will test defactinib as a “maintenance drug” in mesothelioma patients who experienced a partial response or stabilized disease after first-line chemotherapy treatment with pemetrexed (Alimta). Between 350 and 400 mesothelioma patients will be enrolled in the trial at clinical sites in 11 countries including the U.S., U.K., Australia, Canada, South Africa, New Zealand and Europe.

The trial will also test the theory that defactinib could be especially effective in patients with low levels of the biomarker, merlin. Preclinical research has suggested that patients low in merlin might be more susceptible to drugs like defactinib. Mesothelioma patients who meet the eligibility requirements for the trial will have their merlin levels tested and will be sorted into randomized groups. Half will receive 400 mg of defactinib daily while the other half will receive a placebo. Horobin says the company hopes that adding the defactinib aspect to the trial will help “accelerate the program to a potential regulatory decision”.

“This well-designed study is expected to deliver a one-two punch to the tumor by treating with defactinib following first-line therapy… in an attempt to prolong clinical response,” said Professor Dean Fennell, Chair of Thoracic Medical Oncology at the University of Leicester and Coordinating Investigator for COMMAND in the U.K. “There is significant enthusiasm within the mesothelioma community for the COMMAND study.”

Mesothelioma is a rare but aggressive cancer caused by exposure to asbestos. While the incidence of mesothelioma is slowing beginning to drop in the U.S., the disease is not expected to peak in many other countries for decades.

Source:

Verastem Initiates COMMAND: A Registration-Directed Trial of Defactinib in Patients with Mesothelioma, News Release, September 10, 2013, Verastem website.