“You have lung cancer.” These four words usually bring paralyzing dread, and for good reason. Lung cancer is the most devastating of cancers, killing more Americans each year than breast cancer, colon cancer and ovarian cancer combined. But researchers and clinicians are hoping immunotherapy can help make lung cancer a not-so-devastating diagnosis.
Discovering New Hope
Immunotherapy is a way of treating disease or infection using the body’s own immune system. In a recent international study led by Julie Brahmer, M.D., director of the Sidney Kimmel Cancer Center at Johns Hopkins Bayview Medical Center, targeted immunotherapy decreased the risk of death or disease progression in lung cancer patients by 50 percent more than standard chemotherapy. In the same study, patients undergoing immunotherapy experienced a four-month greater increase in progression-free survival than those undergoing chemotherapy.
These are promising results in a clinical trial built on the discovery that certain immunotherapy drugs respond to certain proteins excreted by cancer cells—in this case, PD-L1 proteins abundant in stage 4 non-small cell lung cancer tumors. Across the board, immunotherapy was successful in stopping immune system T cells from bonding with cancer cells carrying PD-L1 proteins on their surface, allowing the T cells to target cancer cells and destroy them.
“This tells us that there are patients who should greatly benefit from getting anti-PD-L1 therapy before chemotherapy,” explains Dr. Brahmer.
Immunotherapy and Antibodies | Slaying Lung Cancer
Medical oncologist Julie Brahmer, M.D., explains how immunotherapy works as a tool in treating lung cancer. Using toys and finger paints, she demonstrates how the immune system attacks cancer cells. Dr. Brahmer discusses why immunotherapy is a promising new treatment that can extend lives in certain cases, helping some people with lung cancer live longer and better lives.
Battling a Complex Fight
What makes the fight against lung cancer such a complex battle is the usual need for immediate and aggressive treatment. Most lung cancer is caught at an advanced stage, requiring high-dose chemotherapy that can cause debilitating side effects for patients already in a weakened state. “It’s often for that reason that half of people with lung cancer die within a year of their diagnosis,” says Dr. Brahmer. “It just becomes too much for the body to take at once.”
This has caused experts to look for new ways to tackle the disease. In recent years, the approach has shifted toward more targeted treatments designed to fight specific cancer mutations, such as advanced non-small cell lung cancer. It was a closer look at this specific mutation that led to the discovery of the PD-L1 protein being excreted from certain lung cancer tumors and bonding with T cells to take down the immune system.
Dr. Brahmer explains that about a quarter of those with advanced non-small cell lung cancer have high levels of the PD-L1 protein in their tumor cells. “We wanted to use immunotherapy to treat these individuals in hopes that it would target and block the PD-L1 protein from being able to compromise T cells and the immune system.”
The immunotherapy was indeed able to slow or stop further tumor growth, without the same side effects as chemotherapy. Patients then were able shrink or eliminate the tumors with follow-up chemo or radiation.
“We showed that immunotherapy can benefit some patients early in their treatment. Our hope is that when we determine the best combinations of immunotherapy and targeted anti-cancer drugs, these patients may never need chemotherapy,” says Dr. Brahmer.
Looking Ahead
Since the treatment is still new and costs are high, Dr. Brahmer is working to determine what types of patients are more likely to benefit from immunotherapy alone. She also plans to more closely study how it can benefit those with lung cancer mutations with lower levels of the PD-L1 protein.
“We don’t want to oversell this, but for someone like me who has worked for years in the field, this is a big deal,” she says. “I have patients who have been receiving immunotherapy treatments for several years. They’ve been able to continue with longer and better lives.”
To request an appointment with the Johns Hopkins Lung Cancer Program, call 410-955-LUNG (5864).