Factors That Determine Treatment
Following a mesothelioma diagnosis, your doctor will typically recommend a specific course of treatment. Factors that typically determine treatment include the type of mesothelioma (pleural, peritoneal, or pericardial), the type of cells in the cancerous tumor(s) (epithelioid, sarcomatoid, or biphasic), or the stage of cancer (1-4).
Other factors include demographics, like age or gender, prognosis, and overall health.
Typically, patients are treated with surgery, chemotherapy, radiation, or a combination of the three. Sometimes, patients don’t respond well to any of the first-time mesothelioma therapies, or simply don’t show any improvement.
Emerging treatments are constantly offering new options for patients who haven’t found success through standard treatment. As science advances, doctors may recommend new clinical trials or treatments as they become available.
New Mesothelioma Trials and Emerging Treatments
Many mesothelioma patients are eligible for new versions of current treatments undergoing tests in clinical trials.
The objective of new therapies and medications is to decrease harmful side effects in patients. Emerging treatments are used in combination with other standard treatments in a multimodal plan. If a new type of therapy is successful, it may be integrated into a standard treatment program and become a new standard of care.
New Treatment Drugs
It’s common for certain drugs to be combined with chemotherapy to prevent or shrink tumor growth. For example, a new drug called Olaparib is being tested in certain types of mesothelioma. The drug is currently being tested in clinical trials, where researchers are trying to determine if it helps slow tumor growth. Several immunotherapy drugs are also being tested in mesothelioma targeting different proteins that stimulate the immune system to attack cancer cells.
Immunotherapy harnesses the power of the body’s immune system, using it as a weapon to fight mesothelioma. New research is making it possible to integrate immunotherapy into standard mesothelioma treatments.
There are several different forms of immunotherapy that have been clinically tested to improve mesothelioma treatments and benefit patients.
Virotherapy treatments involve genetically engineering viruses to work with the immune system and attack cancer cells. This therapy is currently undergoing clinical trials as a treatment for pleural mesothelioma, which affects the lining of the lungs and chest (the pleura).
One Phase 3 trial involves patients who have previously failed standard, or first-line chemotherapy treatments. Doctors inject billions of viruses, which contain a cancer-fighting gene called alpha-2b, directly into the chest, or the pleural, cavity. The goal: to remove genes that allow cancer cells to replicate, and slow or stop tumor growth.
Study participants are divided into two treatment arms: an intervention group and a control group. All patients receive a course of gemcitabine, a chemotherapy drug, but only half of the participants in the trial are receiving the virus that contains alpha-2b. This trial includes more than 300 patients at medical centers around the world and will last around seven years.
Oncologists hope this new virotherapy treatment will further immunotherapy research and create new ways to use the body’s own defenses to fight cancers like mesothelioma.
CAR T-cell therapy uses a chimeric antigen receptor (CAR) T-cell to attack pleural mesothelioma tumors. T-cells are a type of white blood cells and are engineered to fight cancer cells. After being re-created in a laboratory, the cells are injected into the chest cavity. The engineered T-cells attack the mesothelin, a surface protein found on mesothelioma cancer cells.
After years of research, studies have shown CAR T-cell therapy is effective in shrinking mesothelioma tumors. Specific combinations of CAR T-cell therapy worked without any toxic side effects. In a recent study, doctors scanned a group of patients to determine if T-cells helped reduce tumor growth. They also added a drug called anti-PD1, which extends the life of CAR T-cells. The study found the treatment was most effective the longer CAR T-cells survived in the body.
The study has not yet established a long-term approach, but CAR T-cell therapy is a promising step towards fighting diseases like mesothelioma and other cancers. A new clinical trial plans to advance the study in 2020. CAR T-cell therapy is already approved for diseases like lymphoma and leukemia.
Tumor Treating Fields (TTF) is another technology used to disrupt cancer cell division. Novocure’s TTF-100L™ system targets solid pleural mesothelioma tumors using different frequencies. The FDA recently approved this new technology specifically for patients with pleural mesothelioma under Humanitarian Use Device.
The device is placed on the patient’s upper torso and delivers electric currents directly to tumors in the chest cavity, preventing the division, or growth of cancer cells. The system has shown success when combining treatment with ALIMTA™, a first-line platinum-chemotherapy drug.
In recent clinical trials, a majority of patients experienced a partial response, meaning the treatment slowed the spread of mesothelioma tumors. Your doctor will decide if the device is fit for you to use and if it is indicated.
Gene therapy can be defined as the modification in the genetic makeup of cells. The medical community has studied gene therapy for more than two decades, due to advances in molecular genetics and gene transfer technology. Unfortunately, there has been little success with most forms of gene therapy. Despite this, scientists continue to explore different ways of using gene therapy to prevent or treat cancers.
Suicide Gene Therapy
One type, known as ‘suicide’ gene therapy,’ involves transferring genetic material from one organism to another. Suicide gene therapy uses cancer cells as the organism in which genes are being transferred. The new genetic material works within the tumor to kill cancer cells. Neighboring cells can also be killed using gene therapy, which is known as the bystander effect.
Cytokine Gene Therapy
The objective of cytokine gene therapy is to impair tumor growth through gene transfers. An anti-tumor immune response signals tumors to stop growing. This form of therapy is low in toxicity and is applied only to diseased cells, which protects healthy cells in the same area of the body.
Gene-Modified Tumor Cell-Based Vaccination Approaches
This approach uses dead tumor cells and injects them into patients, using them as vaccines against cancer. This form of gene therapy has allowed researchers to modify tumor cells to enhance the immune response. In trials, researchers use a carrier, known as a vector, to encode tumor antigens in an attempt to generate anti-tumor immune responses.