First-line pembrolizumab (Keytruda; Merck) monotherapy provides durable long-term overall survival benefit compared with chemotherapy, according to 3 years’ worth of data presented by Dr M. Reck, Lung Clinic Grosshansdorf, Airway Research Center North (ARCN), Member of the German Center for Lung Research Grosshansdorf/Germany. The presentation was made at the IASLC 2019 World Conference on Lung Cancer.

The findings were based on data from the open-label, phase 3 KEYNOTE-024 trial which evaluated the efficacy and safety of pembrolizumab compared with standard of care (SOC) platinum-based chemotherapies in patients with previously untreated stage IV, programmed cell death ligand (PD-L1) strong expressing non-small cell lung cancer (NSCLC). 

In KEYNOTE-24, patients were randomized to receive pembrolizumab 200mg intravenous (IV) infusion every 3 weeks for 2 years or platinum doublet for 4-6 cycles plus optional maintenance (nonsquamous), with stratification by Eastern Cooperative Oncology Group score of 0 or 1, tumor histology (squamous/nonsquamous), and region (East Asia/non‒East Asia). If disease progression occurred, patients in the chemotherapy arm could cross over to pembrolizumab if they met eligibility criteria. The primary end point was progression-free survival (PFS), as assessed by RECIST 1.1; a key secondary end point included overall survival (OS).

Results from KEYNOTE-24 showed that first-line pembrolizumab significantly improved PFS and OS compared with platinum-based chemotherapy. An analysis of 3-year follow-up data demonstrated that patients treated with pembrolizumab had a median overall survival length of 26.3 months compared with 14.2 months in the chemotherapy arm. Additionally, the pembrolizumab treatment arm showed a 36-month overall survival rate of 43.7% vs 24.9% in the chemotherapy arm. 

Regarding safety, grade 3-5 treatment-related adverse events were less frequent with pembrolizumab compared with chemotherapy, despite having a longer treatment duration (11.1 vs 4.4 months, respectively).

Related Articles

“With more than 3 years’ follow-up, first-line pembrolizumab monotherapy continued to provide durable long-term OS benefit vs chemotherapy despite a majority of patients assigned to chemotherapy crossing over to pembrolizumab,” said Dr. Reck. “And pembrolizumab was associated with less toxicity than chemotherapy. Patients who completed 35 cycles of pembrolizumab had durable clinical benefit and most were alive at data cutoff.”

For more information visit