CHICAGO – The combination of nivolumab plus ipilimumab prolonged progression-free survival (PFS), in comparison with platinum based chemotherapy, as initial treatment for advanced non–small cell lung cancer (NSCLC) patients with a high tumor mutation burden (TMB), regardless of PDL-1 status, according to the first analysis of Checkmate 227.
Median PFS was 7.2 months for patients receiving the immunotherapy combination (95% confidence interval, 5.5-13.2) versus 5.5 months (95% CI, 4.4-5.8) for those receiving platinum-based chemotherapy (hazard ratio for disease progression or death, 0.58; 97.5% CI, 0.41-0.81; P less than .001).
The trial results validate the benefit of nivolumab plus ipilimumab in NSCLC and the role of tumor mutational burden as a biomarker for patient selection, Matthew D. Hellmann, MD, said at the annual meeting of the American Association for Cancer Research.
“Checkmate 227 is the pivotal phase 3 study to validate TMB as an important and independent biomarker to be routinely tested in treatment-naive advanced NSCLC,” he said.
Overall survival data with the combination versus chemotherapy was “encouraging” but not yet complete in patients with high TMB, Dr. Hellmann said.
Results from this first analysis (part 1) of Checkmate 227, a multipart trial, were simultaneously published in the New England Journal of Medicine.
The trial was designed prior to emerging data about TMB. The study was later amended prior to initial analysis to include a second coprimary endpoint evaluating PFS with nivolumab plus ipilimumab versus chemotherapy among patients with a tumor mutational burden of at least 10 mutations per megabase (mut/Mb), irrespective of PD-L1 expression level.