WCLC 2020: Pembrolizumab Plus Chemotherapy for Metastatic NSCLC
Posted: Monday, February 22, 2021
Jhanelle Elaine Gray, MD, of the Moffitt Cancer Center, Tampa, and colleagues conducted the KEYNOTE-189 trial to evaluate the efficacy of pemetrexed-platinum chemotherapy plus pembrolizumab or placebo in patients with nonsquamous non–small cell lung cancer (NSCLC) without sensitizing EGFR/ALK alterations, irrespective of PD-L1 expression. Results showed that the addition of pembrolizumab improved both progression-free and overall survival, and their findings were presented at the International Association for the Study of Lung Cancer (IASLC) 2020 World Conference on Lung Cancer in Singapore (WCLC), held in virtual format in January 2021 (Abstract FP13.02).
In this phase III trial, the researchers focused on 616 patients with previously untreated metastatic nonsquamous NSCLC. Participants were randomly assigned 2:1 to receive pemetrexed-platinum chemotherapy plus either 200 mg of intravenous pembrolizumab or placebo for up to 35 cycles of treatment. Patients also received carboplatin/cisplatin for 4 cycles at the investigator’s discretion. Treatment was continued until unacceptable toxicity or radiographic disease progression, and crossover from placebo to pembrolizumab monotherapy was allowed.
Of the study participants, 410 patients received pembrolizumab plus pemetrexed-platinum, and 206 received placebo plus pemetrexed-platinum. A total of 84 patients initially assigned to the control group crossed over to pembrolizumab monotherapy. The median overall survival for the pembrolizumab and placebo groups were 22.0 and 10.6 months, respectively. The 3-year overall survival rate for the pembrolizumab cohort was 31.3%, and the rate for the placebo cohort was 17.4%. The median progression-free survival for the pembrolizumab and placebo groups were 9.0 and 4.9 months, respectively.
Adverse events of grades 3 to 5 occurred in 72.1% of patients on pembrolizumab and 67.3% on placebo. Of the 56 patients who completed all 35 cycles of treatment, 87.5% had an objective response, and 12.5% achieved stable disease. At data cutoff, 80.4% of these patients were still alive, the 2-year overall survival was 79.6%, and seven patients began a second course of pembrolizumab.
Disclosure: For full disclosures of the study authors, visit wclc.iaslc.org