Timing of Durvalumab Consolidation and Survival in Non–Small Cell Lung Cancer: A Population-Based Analysis

PURPOSE Consolidation durvalumab after concurrent chemoradiation (CCRT) for locally advanced non–small cell lung cancer (NSCLC) extends survival. In the PACIFIC trial, the timing to initiate durvalumab was 1-42 days after CCRT. However, in practice, many patients are treated outside this time frame. This study examined the impact of treatment timing. METHODS We performed an analysis of a nationwide electronic health record–derived deidentified database. Patients with stage III NSCLC diagnosed in 2019-2023 and treated with CCRT were identified. Outcomes were overall survival and time to durvalumab discontinuation (TDD). Sequential landmark and propensity score analyses were performed to investigate timing of durvalumab initiation from week 1 to 13 after CCRT. RESULTS Among 854 patients analyzed, durvalumab was initiated at a median of 5.6 weeks after CCRT (IQR, 4.0-8.3 weeks). When not considering the timing of durvalumab, patients who received durvalumab had better survival than those who did not: adjusted HR, 0.44 (95% CI, 0.34 to 0.56, P < .001). When considering the timing of durvalumab, no significant survival difference was found when durvalumab was initiated on or before week 4: adjusted HR, 0.81 (95% CI, 0.62 to 1.05, P = .07). The survival benefit increased over time and became significant on or after week 5. We found no deterioration in survival benefit when durvalumab was started after week 6. No significant difference in TDD by durvalumab timing was found. CONCLUSION This analysis demonstrated the survival benefit of durvalumab consolidation in the real-world setting. However, the benefit was not significant when durvalumab was initiated on or before week 4 after CCRT.