BACKGROUND: Most patients with locally advanced, unresectable, non-small-cell 
lung cancer (NSCLC) have disease progression despite definitive 
chemoradiotherapy (chemotherapy plus concurrent radiation therapy). This phase 3 
study compared the anti-programmed death ligand 1 antibody durvalumab as 
consolidation therapy with placebo in patients with stage III NSCLC who did not 
have disease progression after two or more cycles of platinum-based 
chemoradiotherapy.
METHODS: We randomly assigned patients, in a 2:1 ratio, to receive durvalumab 
(at a dose of 10 mg per kilogram of body weight intravenously) or placebo every 
2 weeks for up to 12 months. The study drug was administered 1 to 42 days after 
the patients had received chemoradiotherapy. The coprimary end points were 
progression-free survival (as assessed by means of blinded independent central 
review) and overall survival (unplanned for the interim analysis). Secondary end 
points included 12-month and 18-month progression-free survival rates, the 
objective response rate, the duration of response, the time to death or distant 
metastasis, and safety.
RESULTS: Of 713 patients who underwent randomization, 709 received consolidation 
therapy (473 received durvalumab and 236 received placebo). The median 
progression-free survival from randomization was 16.8 months (95% confidence 
interval [CI], 13.0 to 18.1) with durvalumab versus 5.6 months (95% CI, 4.6 to 
7.8) with placebo (stratified hazard ratio for disease progression or death, 
0.52; 95% CI, 0.42 to 0.65; P<0.001); the 12-month progression-free survival 
rate was 55.9% versus 35.3%, and the 18-month progression-free survival rate was 
44.2% versus 27.0%. The response rate was higher with durvalumab than with 
placebo (28.4% vs. 16.0%; P<0.001), and the median duration of response was 
longer (72.8% vs. 46.8% of the patients had an ongoing response at 18 months). 
The median time to death or distant metastasis was longer with durvalumab than 
with placebo (23.2 months vs. 14.6 months; P<0.001). Grade 3 or 4 adverse events 
occurred in 29.9% of the patients who received durvalumab and 26.1% of those who 
received placebo; the most common adverse event of grade 3 or 4 was pneumonia 
(4.4% and 3.8%, respectively). A total of 15.4% of patients in the durvalumab 
group and 9.8% of those in the placebo group discontinued the study drug because 
of adverse events.
CONCLUSIONS: Progression-free survival was significantly longer with durvalumab 
than with placebo. The secondary end points also favored durvalumab, and safety 
was similar between the groups. (Funded by AstraZeneca; PACIFIC 
ClinicalTrials.gov number, NCT02125461 .).