With immunotherapy being a new, and sometimes experimental, treatment for mesothelioma patients, the benefits are still being uncovered. However, so too are the side effects and drawbacks. This month’s news has brought updates on both the pros and cons of immunotherapy, and here we highlight those findings regarding its use as treatment for lung cancer and mesothelioma.
The mesothelioma community has kept a close eye on immunotherapy as reports from across the globe have shown the latest approach to treating this aggressive cancer to be positive. Last week we reported on Mavis Nye, of England, who claims remission from pleural mesothelioma after two years on Keytruda, an immunotherapy drug. Not all patients have seen the same success.
Immunotherapy Experiences Some Setbacks
According to a May 14 article in Business Insider, results for patients who were treated with checkpoint inhibitors like Keytruda, drugs that target proteins that interfere with the immune system allowing the cancers to grow unchecked, have not always been encouraging. The article pointed to several issues with the drugs. Not everyone is responding to the drugs, pointing to one trial where the two-year survival increase was just six percent higher than those taking chemotherapy. In some cases, researchers report the checkpoint inhibitors could be speeding up tumor growth, and some of the drugs in clinical trials have failed. For some patients, the cost of the drugs, that can be more than $100k per treatment, according to the Business Insider, takes the option off the table.
Using CAR T-cell therapy, where a patient’s cells are removed, re-engineered and reintroduced to the body, some patients have seen dramatic results. Unfortunately, cerebral edema, or swelling of the brain, has been a serious side effect leading to four deaths last year in one clinical trial conducted by Juno Therapeutics.
“I feel there is a long way to go,” said Roman Yelensky, the chief technology officer at Gritstone Oncology, a California-based cancer immunotherapy company. “And ultimately if in many cases it’s curing patients, we have to take the risk and then manage the benefits.”
The American Cancer Society (ACS) reports that Keytruda and Opdivo are two immunotherapy checkpoint inhibitor drugs that target PD-1 proteins that act by turning on the immune system’s ‘switch’ to enable the body’s defense mechanisms to fight the cancer. The ACS notes that a concern with PD-1 inhibitors is that the immune system may also attack healthy organs in the body leading to serious side effects in some people.
Bright Spot in Cancer Treatment with Immunotherapy
On the positive side, Swiss researchers report that when these same checkpoint inhibitors are used prior to a chemotherapy regimen patients experience a higher partial response rate. In a May 8 article from Medical News Today, non-small cell lung cancer patients who received salvage chemotherapy are 30 percent more likely to achieve a partial response when pre-treated with a PD-1/PD-L1 checkpoint inhibitor, according to a study from University Hospital Basel, Switzerland.
The immunotherapy drugs the patients received were Opdivo, Keytruda, or Tecentriq, all PD-1/PD-L1 inhibitors.
“This is the first research suggesting that chemotherapy could potentially work better after immunotherapy,” said Marina Garassino, MD, Head of Thoracic Medical Oncology, National Cancer Institute of Milan.
“Checkpoint blockers are transformational,” says Laurie H. Glimcher, MD, president and CEO of Dana-Farber and a prominent immunologist, in a May 11 press release from Dana-Farber Cancer Institute about the progress made in immunotherapy. “However, it’s just the tip of the iceberg.”
Glimcher reports that, thus far, there have been impressive successes with recent immunotherapy advances, but, she adds they are still limited. She says that it is important “to bring the strategy to more patients and more kinds of cancer” in order to realize the full potential of immunotherapy.
Mesothelioma is an aggressive cancer and is known to be resistant to standard care. Sometimes clinical trials offer the best survival. Currently, there are a variety of immunotherapy trials for mesothelioma patients. To find what is available check with your physician and check ClinicalTrials.gov.
The best treatment for mesothelioma is one that is personalized to each patients unique characteristics and meets the patients needs. Patients should work closely with their medical team to understand the pros and cons of each treatment option, and they should feel comfortable with their selected treatment protocol.