Mesothelioma is a type of cancer caused by exposure to asbestos fibers. At this point, there is no cure for mesothelioma. There are some promising new treatments, however, which can extend the survival time of mesothelioma patients. Someday, these treatments may even lead to a cure. One of these promising treatments is Keytruda mesothelioma immunotherapy.
What is Mesothelioma Immunotherapy?
Mesothelioma is a cancer that grows in the delicate membranes that protect your lungs or heart or line your abdomen or testicles. The cells of this lining, which is called the mesothelium, are particularly sensitive to the toxic properties of asbestos fibers.
If you have ever worked or lived around asbestos, you may have inhaled some of these fibers. Mesothelioma can develop as long as 40 or 50 years after asbestos exposure. With possibly one of the longest incubation periods of any form of cancer, patients who develop mesothelioma often are faced with researching their work-life history and that of family members to understand the times, places and point(s) of exposure.
One of the reasons that malignant mesothelioma cells may be able to grow and multiply in your body is that they trick the body’s immune system. Immunotherapy drugs see through these tricks and turn the table on cancer cells. Keytruda mesothelioma immunotherapy, though it is a very new mesothelioma treatment, has shown great promise in improving the lives of mesothelioma patients.
How Immunotherapy Works
Immunotherapy leverages the power of your body’s own disease-fighting cells, including a type of white blood cell called T cells.
Cancers are crafty. To keep your immune system from recognizing them as alien growths and neutralizing them, some cancerous cells use tricks to hide from the immune system. These malignancies convince your immune cells that they are normal cells. Nothing to see here, move along, they say (in effect). Don’t mind me. I’m just an innocent little cell.
Because there are several different mechanisms that cancer cells use to evade detection by T cells, there are several different types of immunotherapy drugs. Each drug works on one specific mechanism and blocks the strategy that the cancer cells use to get around your immune system. Every immunotherapy drug will not work on every tumor.
Mesothelioma Immunotherapy vs. Chemotherapy
You may be wondering how immunotherapy drugs are different from chemotherapy drugs. Mesothelioma chemotherapy drugs attack and kill as many cancer cells as possible. Immunotherapy drugs like Keytruda don’t directly go after cancer cells. Instead, they alert the immune system to the invader and let your T cells and other immune system fighter cells do the rest.
How Can Immunotherapy Help Mesothelioma patients?
A number of mesothelioma treatments have been used effectively, especially when the disease is caught in the early stages. Mesothelioma surgery is quite effective in slowing down the progress of mesothelioma, especially when combined with chemotherapy. Almost every patient will receive mesothelioma chemotherapy, even if surgery isn’t possible. Many mesothelioma treatment plans also include mesothelioma radiation therapy.
There are cases, however, where these first-line treatments do little to slow the progress of the disease. In other instances, mesothelioma is diagnosed only in later stages, when it has metastasized or spread to other organs. In these cases, immunotherapy may work where traditional treatments have not.
Clinical trials of Keytruda mesothelioma immunotherapy have showed promising results. Patients were able to remain on the drug for two years or more. Several had reductions in the size of their tumor and their mesothelioma symptoms got better. A few patients had longer than average mesothelioma survival times.
What Are Second-Line Mesothelioma Treatments?
First-line cancer treatments are the proven therapies that have had positive effects for mesothelioma patients in the past. First-line mesothelioma treatments include surgery, certain chemotherapy drugs, and radiation.
Second-line cancer treatments are the therapies that doctors use when first-line treatments don’t work or stop working. Second-line mesothelioma treatments include certain chemotherapy drugs and most immunotherapy treatments.
For some mesothelioma patients, immunotherapy may be a first-line treatment but, at this point, it is almost always used as a second-line treatment when traditional chemotherapy doesn’t work.
What is Keytruda Mesothelioma Immunotherapy?
Keytruda is the brand name of the immunotherapy drug pembrolizumab. It was developed by researchers Gregory Carven, Hans van Eenennaam, and John Dulos in the early 2000s. In 2014, it was given fast track approval by the FDA for use in treating melanoma, a malignant type of skin cancer. It is marketed by the drug company Merck.
Since 2014, pembrolizumab has showed such promising results that the FDA has approved it for treatment of several other cancers, including non-small cell lung cancer, Hodgkin’s lymphoma, and a specific type of head and neck cancer. More recently, Keytruda got the green light to treat some tumors that can’t be surgically removed or are metastatic (i.e. a secondary tumor on another organ, formed by the spread of cancerous cells from the primary tumor).
Pembrolizumab first came into the national spotlight when former President Jimmy Carter got cancer. President Carter announced that he had melanoma and that it had spread to his brain. It didn’t seem that he had long to live. Then, less than a year later, an MRI showed that his brain was cancer-free, thanks to Keytruda treatments. He went off the drugs and won’t resume unless the cancer comes back. This amazing turnaround inspired cancer patients, who petitioned their doctors to put them on the immunotherapy drug that had such a positive result for President Carter.
Some mesothelioma patients are already receiving Keytruda mesothelioma immunotherapy, though it isn’t yet widely available. You can access this drug by participating in a clinical trial or through the Merck Access Program for Keytruda, which provides financial assistance for patients to receive this mesothelioma immunotherapy.
How Keytruda Mesothelioma Immunotherapy Works
To understand how Keytruda mesothelioma immunotherapy works, you it helps to understand a little bit about how your immune system works.
When foreign cells, such as viruses and bacteria, enter your body, an alarm goes off that puts your immune system on alert. The fever that sometimes accompanies the flu is a sign that your immune system is working overtime to kill off the millions of viruscells circulating through your body.
In situations like the flu or the common cold, your immune system almost always beats the invaders. With cancer, the situation is more complex.
When your immune system recognizes disease cells, this spurs the growth of specialized T cells, designed to fight off that specific disease cell’s antigen. There are T cells that destroy cancers. Unfortunately, cancer cells have evolved methods to hide from T cells by pretending to be normal cells.
One of these methods uses the programmed death-ligand 1 or PD-L1. PD-L1 is a protein your body uses to suppress the natural immune reaction. Sometimes this is helpful: when a woman is pregnant, it’s important that her body doesn’t treat the fetus as an intruder and attack it.
Other times, PD-L1 can be used against us. That is just what some types of cancer do: they bind to PD-L1 and make sure the tumor has a lot of this protein. The PD-L1 keeps your immune system from producing the extra T cells it would need to fight off the cancer and the tumor is left to grow unchecked.
Keytruda mesothelioma immunotherapy is called a PD-L1 inhibitor or an anti-PD-L1 monoclonal antibody drug, because it blocks the PD-L1 pathway. This immunotherapy treatment allows your body to recognize the mesothelioma as disease tissue and create the T cells it needs to fight it.
Can Keytruda Help Me?
One of the things that’s important to understand about pembrolizumab mesothelioma immunotherapy (and any type of immunotherapy) is that it won’t work for everyone. Two patients with the same mesothelioma type can have two very different manifestations of the cancer.
The remarkable success of Keytruda mesothelioma immunotherapy involves patients with PD-L1-positive tumors. Not every mesothelioma tumor uses the PD-L1 pathway to evade the immune system, so not every mesothelioma patient will be helped by pembrolizumab.
To determine if your tumor is PD-L1 positive, your doctor will need a tissue sample or biopsy. A biopsy is a small surgery to remove cancerous cells for examination under a microscope. Most mesothelioma patients need a biopsy for a firm diagnosis, so your medical team may already have a tissue sample they can use.
Keytruda mesothelioma immunotherapy can help patients with pleural mesothelioma (affecting the pleura or the lining around the lungs – the most common type of mesothelioma) and peritoneal mesothelioma (affecting the peritoneum or lining around the organs in the abdomen – the second most common type). Preliminary research suggests that about 20 percent of pleural mesothelioma tumors are PD-L1 positive. Some mesothelioma patients have reported significant reductions in the size of tumors after receiving Keytruda mesothelioma immunotherapy.
Pericardial mesothelioma (affecting the pericardium, the sac that protects the heart) and testicular mesothelioma (affecting the tunica vaginalis or the lining in the testes) are extremely rare, so there is not good data on the effects of Keytruda on these two mesothelioma types as yet.
It doesn’t matter which mesothelioma cell type your tumor is (epithelioid, sarcomatoid, or biphasic): as long as it is PD-L1 positive, Keytruda may help.
There are other health issues that can prevent you from being able to take Keytruda mesothelioma immunotherapy. If you have a disease of the liver or kidneys, pembrolizumab could make it worse, so this immunotherapy may not be recommended. Keytruda can sometimes cause inflammation of the lungs, so some patients with breathing problems unrelated to their mesothelioma can’t take the drug. Patients with autoimmune diseases such as Crohn’s disease or lupus can also have problems with this immunotherapy treatment.
Pregnant women should not take Keytruda. As noted above, the PD-L1 suppression of the immune system is important for pregnant women. Pembrolizumab may hurt the baby.
Pembrolizumab or other immunotherapy drugs are sometimes given as second-line treatments, even when your tumor has not been shown to be PD-L1 positive.
What to Expect During Keytruda Mesothelioma Immunotherapy
Keytruda mesothelioma immunotherapy is administered intravenously. Just like a chemotherapy visit, you will go to the treatment center or hospital. You will be hooked up to an IV and will receive the immunotherapy medication for about half an hour. Your next appointment will be three weeks after the first. You will come back every three weeks for up to two years.
Your doctor will stop pembrolizumab immunotherapy treatment if you have a serious negative side effect or if the therapy doesn’t work for you.
On the other hand, if Keytruda mesothelioma immunotherapy is keeping your tumor from growing and metastasizing, you can ask for approval for a third year of this treatment.
Research on Keytruda Mesothelioma Immunotherapy
There is a great deal of excitement about pembrolizumab and other immunotherapies in the cancer treatment community. There are many studies and clinical trials underway to help researchers understand more about the benefits of Keytruda. Some of these studies are testing the effectiveness of Keytruda mesothelioma immunotherapy.
Studies and clinical trials help doctors understand the best dosages and treatment combinations for new therapies. They can also provide information about which patients are most likely to benefit from Keytruda mesothelioma immunotherapy. Cancer treatment is becoming increasingly targeted, so that each patient receives a treatment designed to be most effective for the specific type of cancer cells in their tumor.
When you join a mesothelioma clinical trial, you receive great medical care, observation and checkups from mesothelioma specialists, and cutting edge treatment. If you want to sign up for a clinical trial of Keytruda or other mesothelioma treatment, ask your doctor about trials near you.
Side Effects of Keytruda Mesothelioma Immunotherapy
In studies of Keytruda mesothelioma immunotherapy to this date, no mesothelioma patients had to drop out because of negative side effects. This immunotherapy treatment, for many patients, can have similar side effects to those from traditional chemotherapy drugs.
The most common side effects include:
- Excess tiredness
- Achy joints
Less common but non-life threatening side effects include:
- More serious skin conditions, including severe rashes, vitiligo, acne, or eczema
- Dry eyes
- Dry mouth
- Low blood iron (anemia)
- Loss of appetite
- Loss of sense of taste
- Body pains
- Flu-like reactions such as fever or chills
- Wheezing, shortness of breath
Keytruda mesothelioma immunotherapy does come with some more significant risks, however. The drug blocks the PD1-L1 pathway not just for cancer cells but for healthy ones as well. This can, in some cases, cause your immune system to attack healthy organs. This immunotherapy drug can lead to immune system problems in some patients that require them to take hormones for the rest of their lives.
Keytruda mesothelioma immunotherapy is not recommended for patients with certain other conditions, including diseases of the immune system and organ transplants. Be sure your doctor has your complete medical history so you can both make an informed decision about whether Keytruda mesothelioma immunotherapy is right for you.