Site Editor

David S. Ettinger, MD, FACP, FCCP


ASTRO 2022: 2-Year KEYNOTE-799 Update on Pembrolizumab Plus Chemoradiotherapy in Stage III NSCLC

By: Vanessa A. Carter, BS
Posted: Thursday, October 27, 2022

During the 2022 American Society for Radiation Oncology (ASTRO) Annual Meeting (Abstract 145), Salma K. Jabbour, MD, FASTRO, of Rutgers Cancer Institute of New Jersey, New Brunswick, and colleagues presented an update from the KEYNOTE-799 study of pembrolizumab plus chemoradiation therapy in patients with stage III non–small cell lung cancer (NSCLC). This 2-year follow-up suggests this combination remains a viable treatment option, demonstrating “manageable safety and promising survival outcomes” in this patient population.

This phase II study enrolled 214 adults with unresectable, locally advanced stage III NSCLC with either squamous and nonsquamous (cohort A; n = 112) or nonsquamous alone (cohort B; n = 102) histology. Participants in cohort A received carboplatin, paclitaxel, and pembrolizumab plus standard thoracic radiotherapy. Individuals in cohort B received cisplatin, pemetrexed, and pembrolizumab plus standard thoracic radiotherapy. All individuals received 14 additional cycles of pembrolizumab.

Prior results from this study demonstrated an objective response rate of 70.5% in cohort A and 70.6% in cohort B. The median time from the first dose to data cutoff was 30.2 months in cohort A and 25.4 months in cohort B; objective response rates were 71.4% and 75.5%, respectively. Although the median duration of response and overall survival were not reached in either cohort, the median progression-free survival was 30.6 months in cohort A.

Patients in cohort A and B who had a PD-L1 tumor proportion score of less than 1% had objective response rates of 66.7% and 78.6%, respectively; those with a score of 1% or higher had rates of 77.3% and 72.5%.

Grade 3 or higher pneumonitis affected nine patients in cohort A and seven patients in cohort B. Additionally, treatment-related adverse events of grade 3 or higher were reported in 64.3% and 51.0% of participants in cohort A and B, respectively.

Disclosure: To view Dr. Jabbour’s disclosures, visit

By continuing to browse this site you permit us and our partners to place identification cookies on your browser and agree to our use of cookies to identify you for marketing. Read our Privacy Policy to learn more.