Like many other breakthrough cancer medications, nivolumab is a drug that was first developed for more common types of cancer and is only now being tested for use in malignant mesothelioma. The drug is a monoclonal antibody that works as a checkpoint inhibitor: this means that it works to block a signal that cancer cells send out to protect themselves from T cells attacking them. By blocking the signal, it allows T cells to kill cancer cells. Nivolumab is frequently used in combination with another new drug called ipilimumab, a drug that attacks a protein receptor that makes the immune system slow down. Together, the two are thought to both boost the immune system and clear the way for the bolstered T cells to do their job. Recently, cancer researchers have tested the drugs on patients with relapsed malignant pleural mesothelioma to see whether they provided additional disease control.
Clinical Study Examined Use of Drugs After Chemotherapy Failure
The mesothelioma study was conducted by researchers from the Department of Pulmonary and Thoracic Oncology at the University of Lille in France. According to lead investigator Arnaud Scherpereel and colleagues, the goal was to evaluate whether nivolumab alone or in combination with ipilimumab could provide any survival extension. “There is no recommended therapy for malignant pleural mesothelioma that has progressed after first-line pemetrexed and platinum-based chemotherapy,” Scherpereel explained. “Disease control has been less than 30% in all previous studies of second-line drugs.”
Hoping for 12-Week Disease Control
The study was done on mesothelioma patients at 21 centers throughout France, and focused on patients who had already been treated at least once with first and second-line chemotherapy and platinum=based therapies. The 125 patients chosen all had life expectancies greater than 12 weeks, and were split roughly in half between those receiving nivolumab alone and those receiving nivolumab plus intravenous ipilimumab. The treatment schedule was undefined: it was to be administered until either the disease returned or patients experienced a level of toxicity that made continuing untenable, and the goal was to achieve 12-week disease control in at least 40 percent of patients.
Drug Combination Provides Greatest Success, But Greatest Toxicity
The researchers were able to achieve this goal overall, with the success rate between the two groups showing a higher success rate in patients who received the combination of drugs: 52% of those patients achieved 12-week survival. The study did reveal some toxicity levels in patients, with that negative side effect being seen in more of the patients receiving the drug combination. There were also 3 deaths among those who received the drug combination, with patients succumbing to encephalitis, acute kidney failure and fulminant hepatitis. Overall, the physicians considered their results promising, writing, “Anti-PD-1 nivolumab monotherapy or nivolumab plus anti-CTLA-4 ipilimumab combination therapy both showed promising activity in relapsed patients with malignant pleural mesothelioma, without unexpected toxicity. Although these results require further confirmation in larger trials, they could now justify the use of immune checkpoint inhibitors in patients with relapsed malignant pleural mesothelioma who have no other efficient therapeutic options available.”
Continuing positive results from clinical studies are cause for hope among mesothelioma patients and their loved ones. For information about accessing some of these state-of-the-art treatments, contact the Patient Advocates at Mesothelioma.net at 1-800-692-8608.
