(HealthDay)—For patients with programmed death ligand 1 (PD-L1)-expressing locally advanced or metastatic non-small-cell lung cancer (NSCLC), pembrolizumab is associated with better overall survival than chemotherapy, regardless of the PD-L1 tumor proportion score (TPS), according to a study presented at the annual meeting of the American Society of Clinical Oncology, held from June 1 to 5 in Chicago.
Gilberto Lopes, M.D., from the University of Miami Health System, and colleagues compared pembrolizumab with platinum-based chemotherapy at the lower TPS of ≥1 percent. A total of 1,274 patients with previously untreated advanced/metastatic NSCLC were randomized in a 1:1 ratio to ≤35 cycles of pembrolizumab or no more than six cycles of paclitaxel + carboplatin or pemetrexed + carboplatin with optional pemetrexed maintenance.
The researchers found that 13.7 and 4.9 percent of patients were still on pembrolizumab and were on pemetrexed maintenance, respectively, after a median follow-up of 12.8 months. In patients with TPS ≥50 percent, TPS ≥20 percent, and TPS ≥1 percent, pembrolizumab correlated with significant improvement in overall survival (hazard ratios, 0.69, 0.77, and 0.81, respectively). The frequency of grade 3 to 5 drug-related adverse events was reduced with pembrolizumab (17.8 versus 41.0 percent).
"Our study shows that pembrolizumab provides more benefit than chemotherapy for two-thirds of all people with the most common type of lung cancer," Lopes said in a statement.
Several authors disclosed financial ties to pharmaceutical companies, including Merck, which manufactures pembrolizumab and partially funded the study.
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