New Study Reveals Immunotherapy More Effective Than Chemotherapy

Study results published in the New England Journal of Medicine comparing the efficacy of an immunotherapy with chemotherapy as a second-line treatment for nonsquamous non–small-cell lung cancer (NSCLC) signal a potential turning point in the therapeutic landscape of cancer. The study showed that the PD-1 immune checkpoint inhibitor-antibody nivolumab improved overall survival rate better than a chemotherapy regimen of docetaxel (51% vs. 39%, respectively). Docetaxel is one of the most commonly used second-line treatments for advanced NSCLC, according to a press release from the UT Southwestern Medical Center, which was involved in the study.

Although the overall rate of survival was better with nivolumab, progression-free survival was actually better with docetaxel (median, 2.3 months and 4.2 months, respectively). The rate of progression-free survival after one year, however, was higher with the nivolumab group than with the chemo group (19% and 8%, respectively). The researchers attributed the cause of the lower progression-free survival in the nivolumab group to typical delays in benefit that are associated with treatment with immunomodulators. "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 David Gerber, MD, associate professor of internal medicine at UT Southwestern- a contributing author to the study-in a university press release.

Tumor-expressed ligands PD-L1 and PD-L2 down-regulate activation of T cells to evade attack by the immune system. The researchers concluded that patients whose tumors expressed higher levels of PD-L1 responded better to treatment with nivolumab; 24% of patients continued nivolumab treatment beyond the 12-week study period, and of these 71 patients, 16 (23%) had a “nonconventional pattern of benefit,” according to study researchers. Although the adverse events were generally similar in both groups, a small group of patients in the nivolumab group experienced autoimmune toxicities affecting various organs.