Clinical Trial Results Show Immunotherapy is Effective Against Mesothelioma

Scientists and researchers continue to make strides in finding new approaches to treating the persistent and indefatigable mesothelioma. Chemotherapy, once considered the primary mode of treatment for the terminal cancer, is beginning to take a back seat to immunotherapy. A review of recent clinical trials shows success with immunotherapy where chemotherapy failed in small cell lung cancer and mesothelioma.

Catherine Pietanza, MD, a medical oncologist at Memorial Sloan Kettering Cancer Center, reports that the immune checkpoint inhibitors CTLA-4 and PD-1 “have demonstrated encouraging results for patients with small cell lung cancer (SCLC) and mesothelioma.”

Immune checkpoints are likened to “immunological brakes” that allow tumors to escape detection by the immune system, according to Dendreon Corporation. However, checkpoint inhibitors release those brakes and “may enhance the anti-tumor T-cell response,” thus allowing the patients’ natural defense mechanisms to kick in and fight off mesothelioma and other cancers.

“Pace of development of drugs for these malignancies [lung cancer and mesothelioma] has lagged behind NSCLC,” said Dr. Pietanza in a presentation at the 10th Annual New York Lung Cancer Symposium, according to a Nov. 7 article in OncLive. “Both malignancies are associated with immunogenic effects.”

“The antibodies to CTLA-4, PD-1, and PD-L1 can be safely given to these patients,” said Dr. Pietanza. “Responses are seen and are durable.”

Dr. Pietanza cited results from various clinical trials using the checkpoint inhibitors. In one trial (CheckMate-032 trial), the nine-month progression free survival rates ranged from 10.2% to 30.4% based on whether the patients received single or combination immunotherapy treatment. Patients were given the PD-1 inhibitor nivolumab (Opdivo) or the combination of nivolumab and the CTLA-4 inhibitor ipilimumab (Yervoy).

“Obviously, very impressive is the progression-free survival being 30% with the combo and about 10% at 9 months for nivolumab alone, this is quite impressive,” Dr. Pietanza said.

Ipilimumab and nivolumab are both approved by the FDA to treat melanoma, but they have not been approved as a combination therapy. In March, the FDA approved the use of nivolumab for patients with previously-treated advanced squamous non-small cell lung cancer (NSCLC).

According to Dr. Pietanza, PD-L1 expression is minimal in SCLC, however, “it is quite high in mesothelioma,” making PD-1 inhibitors promising in mesothelioma care.

Dr. Pietanza referred to the Keynote-028 U.S. clinical trial that found the PD-1 inhibitor, Keytruda, to be effective in controlling mesothelioma tumors in three-fourths of patients. Researchers called the results “encouraging.” The drug was approved in Oct. by the FDA for advanced NSCLC.

After analyzing results of the trials using the checkpoint inhibitors, Dr. Pietanza concluded:

“There are numerous ongoing studies in small cell lung cancer utilizing these agents that are open or are about to be open at multiple institutions. I suggest we all look for them and enroll our patients on them—it is the only way that we are going to make very strong conclusions about these agents.”

Dr. Pietanza presented her findings at the 10th Annual New York Lung Cancer Symposium held Nov. 7 in New York.

See MesotheliomaCounsel for more articles on checkpoint inhibitors:
FDA Approval May Offer New Treatment for Mesothelioma Patients
Mesothelioma Community Hopes for the Same “Spectacular” Results As Seen in Melanoma Trial
Opdivo Boosts Survival in Lung Cancer Patients, Could Benefit Mesothelioma Patients
Orphan Drug Designation May Lead to New Immunotherapy Treatment for Mesothelioma

More articles by Nancy Meredith

Nancy Meredith is a blog and web content writer with more than 20 years of professional experience in the Information Technology industry. She has been writing about Mesothelioma for 7 years. Follow Nancy on Google+