Scott J. Antonia, MD
The phase III PACIFIC trial showed significantly improved overall survival with durvalumab (Imfinzi) vs placebo after chemoradiotherapy in patients with unresectable stage III non–small cell lung cancer (NSCLC). Scott J. Antonia, MD, of the Moffitt Cancer Center, Tampa, Florida, reported these results at the International Association for the Study of Lung Cancer (IASCL) 19th World Conference on Lung Cancer held recently in Toronto. The findings were published simultaneously in The New England Journal of Medicine.1
The international double-blind PACIFIC trial included 709 patients with unresectable stage III NSCLC without disease progression after at least 2 cycles of definitive platinum-based chemoradiation. Patients were randomized 2:1 to receive the programmed cell death ligand 1 (PD-L1) checkpoint inhibitor durvalumab (n = 473) or placebo every 2 weeks (n = 236) for up to 12 months as consolidation therapy. Randomization was performed at 1 to 42 days after receipt of chemoradiotherapy.
As of data cutoff in March 2018, overall survival at 24 months was 66.3% in the durvalumab group vs 55.6% in the placebo group (P = .005). The median overall survival was not reached (95% confidence interval [CI] = 34.7 months to not reached) vs 28.7 months (95% CI = 22.9 months to not reached). The stratified hazard ratio for overall survival for durvalumab vs placebo was 0.68 (P = .0025). The overall survival benefit with durvalumab was observed across all prespecified subgroups.
An earlier report from the PACIFIC trial supported the approval of durvalumab in this setting in February 2018 on the basis of improved progression-free survival. The PACIFIC study was funded by AstraZeneca.
A full report on this and other trials reported at the IASLC 19th World Conference on Lung Cancer will be published in the next issue of The ASCO Post. You may also visit www.ASCOPost.com. ■
1. Antonia SJ, et al: N Engl J Med. September 25, 2018 (early release online).