Imfinzi Plus Chemotherapy Reduced Risk of Death by One-Third in Stage III NSCLC

A phase 3 trial studying durvalumab (Imfinzi) among patients with stage III unresectable non­—small cell lung cancer (NSCLC) who did not have disease progression after concurrent chemoradiotherapy has found that durvalumab improved overall survival, according to drug manufacturer AstraZeneca.

In an earlier analysis of the phase 3 PACIFIC trial, researchers found that durvalumab significantly prolonged progression-free survival (PFS), the primary endpoint of the study, compared with placebo among patients with stage III NSCLC. This week, researchers presented data for the secondary endpoint of the trial, overall survival, during the World Conference on Lung Cancer in Toronto, Canada.

The trial enrolled 713 patients with stage III unresectable NSCLC. Researchers randomly assigned patients 2:1 (473 patients received durvalumab, 236 received placebo) to receive durvalumab intraveneously at a dose of 10 mg per kilogram of body weight, or matching placebo every 2 weeks for up to 12 months.

The results from the trial showed that durvalumab plus chemotherapy significantly improved overall survival compared with the standard of care, chemotherapy alone, regardless of PD-L1 expression. Specifically, researchers found that durvalumab reduced the risk of death by 32% (HR 0.68, 99.73% CI 0.47-0.997; P = .0025). The 24-month overall survival rate was 66.3% (95% CI, 61.7 to 70.4) compared with 55.6% in the placebo group (95% CI, 48.9 to 61.8; 2-sided P = .005).

“These data establish Imfinzi as the first immunotherapy to demonstrate an overall survival benefit for patients with unresectable, stage III non-small cell lung cancer following chemoradiation therapy. today’s announcement brings new hope to patients in a setting where survival rates have not changed in decades,” Sean Bohen, executive vice president of Global Medicines Development and chief medical officer at AstraZeneca, said in a statement.

Additionally, the safety and tolerability profile for durvalumab was consistent with that reported at the time of the PFS analysis. Among patients in the trial who were randomized to receive durvalumab, the most common adverse reactions (greater than or equal to 20% of patients) versus placebo were cough, fatigue, dyspnea, and radiation pneumonitis.

Durvalumab is currently approved in the United States, European Union, Canada, Switzerland, India, Japan, and Brazil based on results from the PACIFIC trial.

Reference

Antonia S, Villegas A, Daniel D, et al. Overall survival with durvalumab after chemoradiotherapy in stage III NSCLC [published online September 25, 2018]. N Engl J Med. doi: 10.1056/NEJMoa1809697