First line pembrolizumab monotherapy provides durable long-term overall survival benefit compared to chemotherapy, according to data presented today 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, hosted by the International Association for the Study of Lung Cancer.

Dr. Reck and his research colleagues had previously presented preliminary data on KEYNOTE-024 and he is now sharing three years' worth of data on these patients.

In the phase III KEYNOTE-024 trial, first-line pembrolizumab significantly improved progression free survival and overall survival compared with platinum-based chemotherapy in patients with advanced non-small cell lung cancer with a PD-L1 tumour proportion score of equal to or greater than 50 percent, and no targetable EGFR/ALK alterations.

Patients were randomised to pembrolizumab 200 mg for two years or platinum doublet for four to six cycles plus optional maintenance (nonsquamous), with stratification by Eastern Cooperative Oncology Group score of 0 or 1, tumour histology (squamous/nonsquamous), and region (East Asia/non?East Asia).

Patients in the chemotherapy arm could cross over to pembrolizumab upon disease progression if they met eligibility criteria.

The primary endpoint was progression-free survival and overall survival (OS)was a key secondary endpoint.

The median overall survival length among patients in the pembrolizumab arm was 26.3 months compared to 14.2 months in the chemotherapy arm.

The 36-month overall survival rate was 43.7 percent in the pembrolizumab arm vs 24.9 percent in the chemotherapy arm.

Despite longer mean treatment duration in the pembrolizumab arm (11.1 vs 4.4 months), grade 3?5 treatment-related adverse events were less frequent with pembrolizumab vs chemotherapy.

Initial results showed in addition activity for a re-exposure to pembrolizumab for those patients, who had progressed after having received two years of treatment with pembrolizumab with a response in 7 out of 10 patients (70 percent).

"With more than three 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."

Source: The International Association for the Study of Lung Cancer