Clinical Trial Demonstrates Superior Results With Immunotherapy vs Chemotherapy for Lung Cancer
An international team of cancer researchers announced game-changing results in the treatment of certain lung cancers that failed to respond to first-line therapies.
Researchers compared nivolumab, an immunotherapy, with a chemotherapy drug in patients with non-squamous non-small cell lung cancer (NSCLC) whose disease continued to progress after first-line chemotherapy. They found that nivolumab improved overall survival and was generally well tolerated. The results, reported in the New England Journal of Medicine (2015; doi:10.1056/NEJMoa1507643), are significant because options for patients whose lung cancer progresses after initial treatment are limited.
"This clinical trial shows that people with lung cancer not only live longer when treated with the immunotherapy drug nivolumab, but their quality of life is better and toxicities are fewer and less severe," said contributing author David Gerber, MD, associate professor of Internal Medicine at The University of Texas (UT) Southwestern.
According to the National Cancer Institute, lung cancer is the second most common cancer for both men and women, and the top cause of cancer death. It affects more than 221,000 Americans each year. Five-year overall survival is only 17% and even lower for metastatic lung cancer.
The Food and Drug Administration (FDA) approved the use of nivolumab for squamous NSCLC in March 2015 and previously had approved the drug to treat patients with treatment-resistant metastatic melanoma and melanoma that cannot be removed via surgery.
Nivolumab is an immunotherapy drug that inhibits the cellular pathway known as PD-1 protein on cells that block the body's immune system from attacking cancerous cells.
"The idea behind immunotherapy is to kick-start the body's natural immune response to a cancer. Cancer develops and grows in part because it has put the brakes on the immune response. These drugs take the foot off the brake, allowing the immune system to accelerate and attack the cancer," said Gerber, co-director of the Lung Cancer Disease Oriented Team and co-leader of the Experimental Therapeutics Program at UT Southwestern.
Gerber said immunotherapy is one of the greatest medical advances in cancer treatment in the past 30 years. Nivolumab treatment is promising because the drug is effective, often well-tolerated, and appears to be beneficial in several types of cancer.
This study compared nivolumab to docetaxel, a standard chemotherapy agent and one of the most commonly used FDA-approved second-line treatments for advanced NSCLC.
The phase 3 clinical trial followed more than 500 patients who had non-squamous NSCLC: 287 patients received nivolumab and 268 received docetaxel. The 1-year survival rate was 51% in the nivolumab arm vs. 39% in the docetaxel arm. The most commonly reported side effects with nivolumab were fatigue, nausea, decreased appetite, and weakness, and they were less severe than with docetaxel treatment. In a minority of cases, patients treated with nivolumab also developed autoimmune toxicities affecting various organs.
In addition to studying safety and efficacy, the trial examined the protein biomarker PD-L1, which is believed to play a role in suppressing the immune system. The study results suggested that patients with a higher level of PD-L1 in their cancers may experience the greatest benefit with nivolumab.
Using a biomarker helps oncologists predict which patients will do best on which treatment, and plan their treatment accordingly. Other promising predictive biomarkers for cancer immunotherapies include the degree of immune cell infiltration within a tumor and the number of mutations a tumor has.