While the therapy holds potential, researchers are still learning about how it affects ovarian cancer. Most people with ovarian cancer will discover they have the disease when it’s already spread, or metastasized, to other parts of their body. Standard treatments, which usually include surgery and chemotherapy, are effective, but the cancer frequently returns. (1) Though only limited research currently supports the effectiveness of immunotherapy for ovarian cancer, it could one day be a standard of care for some patients. (2) RELATED CONTENT: Large Study Finds No Link Between Use of Talcum Powder in Genital Area and Ovarian Cancer
How Does Immunotherapy Work?
Your immune system attacks foreign substances and is your body’s defense against infections. Cancers are technically foreign to your body, so they should be recognized by the immune system. In patients who have cancer, however, often the immune system has been evaded or hijacked by the cancer through multiple mechanisms. The aim of new immunotherapies is to boost the natural defenses of your immune system toward cancer so that it can work more efficiently and overcome the ways in which cancer avoids being detected and killed by your immune system. (3,4) RELATED: Cancer Risk Genes: Everything You Need to Know About MLH1
What Types of Immunotherapy Are Available?
Many types of immunotherapies are available or being studied to treat cancer, including:
Checkpoint Inhibitors These therapies block proteins on immune cells called “checkpoints,” which hinder the immune system’s ability to “see” and attack cancer. When the checkpoints are turned off, your immune system can better recognize and kill cancer cells.Chimeric Antigen Receptor (CAR) T Cell Therapy With CAR T cell therapy, special T cells (a type of white blood cell) are removed from your body and modified in a lab. The enhanced cells are then placed back in your body, so they can find, attach to, and kill cancer cells.Cytokines This therapy uses cytokines (small proteins that carry messages between cells) to rouse the immune cells to attack cancer.Immunomodulators They work by boosting parts of the immune system.Vaccines Cancer vaccines teach T cells to respond to certain tumor antigens (substances that cause an immune response).Oncolytic Viruses With this treatment, doctors give patients modified viruses to infect and kill cancer cells.Monoclonal Antibodies These are lab-made molecules that target specific antigens found on cancer cells.
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What Types of Immunotherapy Are Being Used and Studied for Ovarian Cancer?
Scientists are still learning how to best use immunotherapy to benefit patients with ovarian cancer. Some studies have shown that certain immunotherapies used alone show benefit in only about 10 to 15 percent of patients. But researchers are testing combinations of the different treatments along with chemotherapy, which may produce a better response. (2) The Food and Drug Administration (FDA) has approved only one immunotherapy, bevacizumab (Avastin), for certain patients with advanced ovarian cancer. (5) Bevacizumab is a monoclonal antibody that works by blocking a protein called vascular endothelial growth factor (VEGF), which normally signals new blood vessels to form. Cancer needs nutrients from the blood to live and grow, so this therapy may help slow or stop cancer growth. The drug has worked to shrink tumors and slow the progression of some advanced ovarian cancers, but it hasn’t been found to increase survival. Bevacizumab seems to work better if it’s given along with chemotherapy. This medicine is infused into a vein, usually every two to three weeks. (6) Many studies are being conducted to examine the effectiveness of different types of immunotherapy for ovarian cancer. Some of these involve using checkpoint inhibitors that target special proteins called PD-1 and PD-L1. Others combine different immunotherapies with chemotherapy. Poly(ADP)-ribose polymerase (PARP) inhibitors — drugs that target a tumor’s ability to repair DNA — are also used in combination with immunotherapies. (5) Some PARP inhibitors used to treat advanced ovarian cancer include olaparib (Lynparza), rucaparib (Rubraca), and niraparib (Zejula). (6) Oncolytic virus therapy, vaccines, and other types of immunotherapy are also being evaluated in patients with ovarian cancer. (7)
How Effective Is Immunotherapy for Ovarian Cancer?
Researchers are still trying to determine the effectiveness of immunotherapy for ovarian cancer. One study found that giving women chemotherapy after treatment with immune checkpoint inhibitors improved survival in some patients. This suggests that immunotherapy may improve the body’s response to chemotherapy. Specifically, researchers found that median overall survival after treatment with chemotherapy following immunotherapy was 18.3 months, which was a positive outcome when compared with other studies. (7) Findings also revealed that survival for a subgroup of women who received a platinum-based chemotherapy regimen after being treated with checkpoint inhibitors was 7.3 months compared with 3.7 months for women who received other therapies. (7) Results from another clinical trial showed that immunotherapy along with standard chemotherapy prolonged survival in women with ovarian cancer that had recurred. (8) Women who received dendritic cell–based immunotherapy (a type of vaccine) plus chemo had a median overall survival of 35.5 months. Those who received only chemo survived an average of 22.1 months. (9) While these results are encouraging, these are small studies and the medications are not yet FDA approved or widely available, as larger studies need to be done to confirm the effectiveness of immunotherapy and which combinations work best for patients with ovarian cancer.
Side Effects of Immunotherapy
Side effects of immunotherapy depend on the type used. (10) Some possible side effects of bevacizumab include: (11)
HeadacheHigh blood pressureToo much protein in the urineNosebleedsRectal bleedingBack painDry skinChanges in tasteInflammation of the skin or noseWatery eyes
Finding a Clinical Trial for Immunotherapy
Here are some questions you might want to ask your healthcare provider before starting on immunotherapy: (12)
Am I a candidate for immunotherapy?What types of immunotherapy are available for my condition?What types of immunotherapy are available in clinical trials?How might immunotherapy help my cancer?What are the possible side effects?How much does immunotherapy cost? Will my insurance cover it?How long will I need to stay on this treatment?How will immunotherapy impact my daily life?
How to Find a Clinical Trial
If you’re interested in immunotherapy, joining a clinical trial might be a good option. These studies may give you the opportunity to receive treatments that aren’t available otherwise. Many trials testing immunotherapy for ovarian cancer are being conducted around the country. You can search for different studies in your area at ClinicalTrials.gov. Additionally, the Cancer Research Institute offers a Cancer Immunotherapy Clinical Trial Finder, which will help you identify trials near you.
