Immunotherapy treatments are becoming known alternatives to chemotherapy in cancer patients who have had little success with traditional cancer treatments. With mesothelioma, often times first line treatments have little effect because the cancer is typically in the advanced stages by the time it is detected. While there currently is no cure for mesothelioma, scientists and researchers have been continually testing for new treatments that will lessen symptoms and increase survival. The aggressive nature of mesothelioma averages a survival rate of 12 months from the time of diagnosis. With the help of some immunotherapy treatments, some patients are able to exceed the average survival rates which allows for scientists and researchers to make adjustments to their treatments to better them for future patients.
Opdivo and Yervoy
Opdivo (Nivolumab) was approved was approved by the FDA as a lung cancer treatment in early 2015, but only for those who had a specific type of lung cancer: squamous, NSCLC, and advanced malignancies that are no longer responding to traditional platinum-based therapies such as pemetrexed and cisplatin.
Opdivo is an immunotherapy treatment, which means it works with the body’s own immune system to kill cancer cells without the use of heavy drugs. By strengthening the immune system or providing synthetic immune proteins, immunotherapy treatments are increasingly becoming a more effective and positive way to treat many types of cancer. Opdivo, like Keytruda (pembrolizumab), is a checkpoint inhibitor. Checkpoint inhibitors are designed to stop immune cells from attacking the good and normal cells in the body – the cells needed to fight off infections. When tumors develop, like that of lung cancer and mesothelioma, it produces the protein PD-L1 that attaches itself to immune cells (PD-1), garnering them ineffective and the immune system begins to fail.
Opdivo, when administered, binds to the immune cell that is being attacked, therefore preventing the PD-L1 protein from the tumor to be able to attach to PD-1. As a result, the immune system is not compromised.
Along with Opdivo is Yervoy (ipillmumab), another immunotherapy treatment designed to utilize the body’s own natural defenses. Yervoy increases the activity of T-cells, which can help fight cancer. A study done by the Pulmonary and Thoracic Oncology Department at the University Hospital in France recently investigated these two therapeutic options – Opdivo by itself, and as a combined treatment with Yervoy. The Phase II clinical trial, called MAPS-2, included 125 mesothelioma patients with a median age of 72 years. Patients were randomly assigned to either receive Opdivo, or a combination of Opdivo and Yervoy. Patients received the treatment until the cancer worsened, but on average patients received about three cycles.
The combination treatment of Opdivo and Yervoy yielded better results with 26 percent of patients seeing a reduction in tumor size and 5.6 months between their current state and their cancer worsening. Only 17 percent of the group that received Opdivo by itself saw a reduced tumor size and the average time it took for the cancer to worsen was only 4 months.
The overall survival rate could not accurately be measured when comparing these two treatments because over half of those who received the combination treatment are still alive. However, the average survival rate for those who just received Opdivo was 10.4 months.
Comparing to Keytruda
Earlier this year, scientists and researchers excitedly presented data at the 17th World Conference on Lung Cancer about the positive effects that Keytruda was having not only by itself, but when combined with CRS-207 – a Listeria based therapeutic vaccine. Similar to Opdivo, Keytruda is a check-point inhibitor that had success increasing the overall survival rate of mesothelioma patients; up to 18 months.
For NSCLC, clinical trials did show more promising results for Keytruda overall. However, the Phase III clinical trial, backed by Merck, targeted smaller groups of lung cancer patients who also tested positive for the biomarker that naturally works with Keytruda. Bristol-Myers Squibb’s clinical trials of Opdivo tested a broad population of lung cancer patients, so their overall results included more unique characteristics and did not have as much of a narrow focus.
Sources:
ASCO 2017: “Early Research Suggests First Immunotherapy for Mesothelioma on the Horizon,” The ASCO Post (June 2017). [Link]
Arnaud Scherpereel, et. al., “Second- or third-line nivolumab (Nivo) versus nivo plus ipilimumab (Ipi) in malignant pleural mesothelioma (MPM) patients: Results of the IFCT-1501 MAPS2 randomized phase II trial,” (June 5, 2017). [Link]
