Immunotherapy Nearly Doubles Survival Rate in Lung Cancer Patients

Nivolumab extends life by 3.2 months compared with chemotherapy.

The survival of patients with a common form of lung cancer was significantly extended by immunotherapy compared with chemotherapy during a recent trial.

Published in the May 31, 2015 edition of the New England Journal of Medicine, the trial showed that squamous-non-small cell lung cancer patients who received nivolumab lived an average of 3.2 months longer than patients who received chemotherapy.

Patients in the nivolumab treatment arm had a survival rate of 42%, compared with 24% in the chemotherapy treatment arm.

"This solidifies immunotherapy as a treatment option in lung cancer," said Julie Brahmer, MD, director of the Johns Hopkins Kimmel Cancer Center Thoracic Oncology Program, in a press release. "In the 20 years that I've been in practice, I consider this a major milestone.”

The researchers noted that the modest median survival time increase from treatment with new immunotherapy drugs may cause confusion in terms of the overall impact from these medications. Dr. Brahmer added that 1- and 2-year survival outcomes data may shed more light on the efficacy of immunotherapies than will overall median survival rates.

"Patients who respond to immunotherapy tend to continue their responses for long durations, and these lengthier responses are cut off in calculations of median overall survival," Dr. Brahmer said.

Nivolumab is part of a drug class dubbed checkpoint inhibitors, which disrupt a signaling system that allows cancers to avoid detection and death by immune cells. These checkpoint inhibitor drugs prevent a connection between receptors on immune cells, which causes the immune cells to target cancer cells for destruction.

The trial included patients with advanced, squamous non-small cell lung cancer whose disease had progressed despite initial chemotherapy. The researchers randomly assigned 135 patients to the nivolumab group and 137 patients to receive the chemotherapy drug docetaxel.

Median overall survival in the nivolumab cohort was 9.2 months, compared with 6 months in the docetaxel cohort. At the 1-year mark, 57 patients in the nivolumab group were still alive, compared with 33 patients in the docetaxel group.

Approximately 20% of patients in the nivolumab group responded to the drug, compared with 8.8% in the docetaxel group. Median disease-progression free survival in the nivolumab group was 3.5 months, compared with 2.8 months in the docetaxel group.

Nivolumab was also found to decrease the relative risk of lung cancer death by 41% compared with docetaxel.

There were also significantly more severe adverse events in the docetaxel group (55%) than in the nivolumab group (6.9%). Common side effects from nivolumab were fatigue, decreased appetite, weakness, and colon, kidney, or lung inflammation. Common side effects from docetaxel were hair loss, fatigue, nausea, diarrhea, and low white blood cell counts.

"Immunotherapy can produce severe side effects, and it's important to be vigilant in efforts to manage them. However, it is less toxic than chemotherapy," Dr. Brahmer said. "Generally, about 20 to 25% of patients with lung cancer are responding to checkpoint blockade inhibitors."