Could immunotherapy, a type of cancer treatment that uses your body’s own immune system to fight tumors, help people with mesothelioma? Early research shows benefits for this hard-to-treat form of cancer.
Mesothelioma often starts in your pleura, a thin lining between your lung and the inside of your chest. Usually, it affects people who’ve breathed in asbestos, a material used in roofing and insulation. Tiny asbestos fibers go into your lungs and cause cancer cells to grow in the lining.
Right now, the only FDA-approved mesothelioma treatments are chemotherapy, like cisplatin, gemcitabine, and pemetrexed. Doctors are looking at other options, like immunotherapy, that could offer hope.
Where Is Immunotherapy Now?
This type of treatment is approved for another type of cancer, melanoma. It’s helping -- and sometimes curing -- it, with fewer side effects than chemo. Still it’s early days for immunotherapy. As more and more people use it, they’re starting to notice side effects doctors didn’t spot during earlier clinical trials.
Larger trials with more mesothelioma patients will offer a better look at how well immunotherapy works and what side effects it can cause.
These drugs are being studied for mesothelioma now:
- Atezolizumab (Tecentriq)
- Nivolumab (Opdivo)
- Pembrolizumab (Keytruda)
How Does Immunotherapy Work?
Unlike chemotherapy drugs, which kill both cancer and healthy cells, immunotherapy is more targeted.
It spurs your own defenses to fight the cancer. White blood cells in your immune system spot cells that aren’t supposed to be in your body, like bacteria or viruses. Immunotherapy drugs tell the white blood cells to sense certain proteins on the surface of cancer cells, then seek out and destroy those cells.
Block the Blocker
It sounds simple, but in mesothelioma, these proteins can block your immune system’s attack. They’re called checkpoints. They distract your white blood cells so they don’t attack the cancer inside. Checkpoint proteins include PD-1 and PD-L1.
Immunotherapy drugs like durvalumab, nivolumab, and pembrolizumab are called checkpoint inhibitors, because they block the proteins’ defense. Checkpoints normally act as an off switch for immune cells attacking tumor cells. Immunotherapy reveals the tumor cells. The checkpoint inhibitor pulls the mask off so the immune cells can do their job.
When Is It Used?
Mesothelioma is hard to treat because its tumor cells are high in checkpoints. So current trials test different mixes of immunotherapy drugs, as well as use of immunotherapy to rev up your immune system before cancer surgery.
The results: People who’ve failed other treatments often respond well to immunotherapy.
Right now, immunotherapy is mainly given to people with mesothelioma in clinical trials.. So how and when do you know if you should sign up for one?
Every trial is different. Each has its own requirements for who can enroll based on the type of mesothelioma you have and what treatments you’ve already tried that didn’t work.
You and your doctor can talk about immunotherapy when you’re diagnosed and go over your treatment options. The type of mesothelioma you have and how far it has spread will help you decide if you should try chemotherapy or surgery first. Usually, you go into a drug trial if other treatments have failed. But some mesothelioma immunotherapy trials don’t require that.
How Do You Take Immunotherapy?
These drugs are all given as infusions, so you go to a clinic to get an IV drip every 2 to 3 weeks.
In early trials, immunotherapy doesn’t seem to have as many side effects as older drugs. But that doesn’t mean there aren’t any. It can cause diarrhea, nausea, muscle and joint pain, rash, or even organ inflammation. As more people take these drugs, we’ll know more about what side effects they could cause.
Researchers want to find biomarkers, like genes or those proteins on the tumors, that could help immunotherapy drugs better hit their targets. Also, most people don’t respond to a single drug, so scientists are looking into combinations with surgery, other cancer drugs, and other immunotherapies.
More trials on more patients with mesothelioma may tell us how well they work in different types of this cancer, and why they seem to work when other drugs have failed. Doctors will go back and figure out why people had the response they did, whether it was partial or very good.
One day, you might not have to wait until other treatments fail first to try immunotherapy. If things keep going the way they are, it could soon become a front-line treatment for mesothelioma.