Immunotherapy

Excitement is growing in the oncological community over impressive results from immunotherapy, a revolutionary approach to cancer treatment. The beauty of immunotherapy that it utilizes and enhances the body’s power to fight disease. A series of clinical studies showed the treatment’s remarkable ability to shrink tumors and extend the life of patients. Researchers predict immunotherapy will replace chemotherapy as the new standard of treatment for many forms of cancer—and soon.

This treatment stimulates the body’s immune response to target cancer cells. Discovered in the 1890s, it was soon overshadowed by other cancer treatments such as radiation. However, immunotherapy treatments are now found in many forms, from vaccines for cervical and pancreatic cancers to drugs such as nivolumab for lung cancer and melanoma.

Modern immunotherapy is designed to serve two functions—bolstering the strength of the immune system and training it to be more efficient in fighting cancer. The immune system acts as a security patrol for the body, detecting and killing abnormal cells. Immunotherapies aid this process in three ways:

Monoclonal antibodies:

These synthetic proteins target specific antigens produced by cancer cells. The antibodies are introduced to the immune system on their own (naked antibodies) or delivered attached to toxins via chemotherapy or radiation (conjugated antibodies), acting as homing beacons to seek out cancer cells.

Cancer vaccines:

Vaccines stimulate the body’s immune response to attack cancer cells. They can be customized in a lab to a patient’s specific needs for optimal results. Vaccines are currently being tested to treat a variety of cancers.

In 2014, a new pancreatic cancer vaccine nearly doubled the survival rate of patients and was given a “Breakthrough Treatment” designation by the FDA.

Non-specific immunotherapy:

This category of treatment improves the immune system while helping it kill cancer cells. One such treatment is drugs called checkpoint inhibitors. Clinical trials show that checkpoint inhibitors may be the new standard in the treatment of skin and lung cancers, among others.

The body has evolved checkpoint proteins on the membranes of healthy cells to protect them from being attacked by their immune system. Cancer cells often go undetected because they “disguise” themselves with checkpoint proteins, and T cells that normally would destroy the cancer end up destroying themselves.

These drugs suppress the efficiency of checkpoint proteins, thus unmasking cancer cells and allowing the body to attack them. Until recently, immunotherapy treatments using checkpoint inhibitors weren’t effective at differentiating healthy tissue from cancerous tissue, which caused significant side effects. However, new advances in immunotherapy drugs introduced at the annual meeting of the American Society of Clinical Oncology in 2015 identify a certain protein (called PDL1) and specifically target it around cancerous tumors while ignoring healthy cells.

In certain forms of cancer, it can be. For example, the immunotherapy drug, nivolumab, has extended the lives of study participants in the final stages of lung cancer who didn’t respond to chemotherapy. On average, patients with advanced stage squamous-cell lung cancer are predicted to live 9.4 months after a full course of chemo. Participants on nivolumab lived an average of 12.2 months—a 27 percent reduced risk of death.

Thus far, the FDA approved nivolumab for the treatment of metastatic squamous non-small cell lung cancer, but researchers are hopeful it will receive approval for treatments of other forms of cancer soon. The prediction is that immunotherapy drugs might treat more than 60 percent of cancers in the next decade. The side effects are less severe than those experienced with chemo or radiation. Common side effects include flu-like symptoms such as nausea, fatigue, fever, chills, diarrhea, and vomiting. Some patients have mild allergic reactions due to the introduction of proteins to the body.

Many new immunotherapy treatments are in early clinical trials and have yet to be approved by the FDA. The first approved immunotherapy drugs have stratospheric prices—a month’s supply of one drug has a price tag of more than $40,000. However, studies of these drugs show that a few months’ worth of treatment can extend the life of a patient by years. A full course of radiation treatment, by comparison, costs around $100,000. Cancer patients should consult their physicians to discuss eligibility for immunotherapy studies and explore the best treatment available to them.