Background: Preliminary analyses of an ongoing Phase 1/2 study of single-agent durvalumab showed antitumor activity and a tolerable safety profile in advanced NSCLC, with higher ORR and longer OS in pts with high vs. low/negative PD-L1 tumor expression. Here we present updated safety analyses (primary endpoint) for all NSCLC pts and clinical activity based on investigator-assessed RECIST v1.1 in pts who had received prior treatment for advanced NSCLC. Methods: Durvalumab (10 mg/kg q2w) was given until unacceptable toxicity or disease progression, or for up to 12 mos; retreatment was permitted upon disease progression after completion of 12 mos of treatment. PD-L1 expression was assessed using the Ventana PD-L1 (SP263) Assay (PD-L1 high = ≥25% and PD-L1 low/negative = <25% of tumor cells with membrane staining). Results: As of 24 Oct 2016, 245 pts with previously treated NSCLC (53% squamous) received durvalumab and were followed for a median of 29.2 (range 0.3–40.5) mos; 142 pts (58%) had treatment-related adverse events (AEs), most frequent: fatigue (18%), decreased appetite (9%), and nausea, rash, and diarrhea (each 8%). 25 pts (10%) had treatment-related Grade 3/4 AEs, most frequent: fatigue and hyponatremia (each 2%); there were no treatment-related deaths. 4% had treatment-related serious AEs including colitis and pneumonitis (each 2%). In the overall population, 12 mo OS rate was 47% (95% CI 40–53) and 18 mo OS rate was 38% (95% CI 31–45). Antitumor activity and survival by PD-L1 status are shown in the table. Conclusions: Consistent with earlier reports, durvalumab had a manageable safety profile in Stage IIIB/IV NSCLC, with encouraging clinical activity as 2L+ therapy. Higher tumor PD-L1 expression enriched clinical benefit of response rate and survival endpoints. Clinical trial information: NCT01693562

Note: 17 patients had unknown PD-L1 expression. ^aResponse evaluable population.