Durvalumab After Chemoradiotherapy in Patients With Unresectable Stage III Non-Small Cell Lung Cancer.

Importance: The PACIFIC trial established consolidation durvalumab as the standard of care following chemoradiotherapy (CRT) for patients with unresectable stage III non-small cell lung cancer (NSCLC). Understanding its benefit in routine US clinical practice is critical.

Objective: To report characteristics, treatment patterns, and outcomes of patients who did or did not receive durvalumab.

Design, Setting, And Participants: Two prespecified cohorts were curated in this retrospective cohort study (SPOTLIGHT). Deidentified patient-level data from a US database (Flatiron Health) were analyzed. Patients had unresectable stage III NSCLC, were diagnosed on or after January 1, 2011, had 2 or more visits on or afterward, and received CRT. Data were analyzed from May 2021 to October 2023.

Exposures: Patients started durvalumab after CRT (durvalumab cohort) or ended CRT without durvalumab (nondurvalumab cohort) by June 30, 2019, to allow 15 or more months of follow-up from CRT end.

Main Outcomes And Measures: End points included progression-free survival (PFS), overall survival (OS), time to first subsequent therapy or death (TFST), and time to distant metastasis or death (TTDM).

Results: The durvalumab cohort included 332 patients (median [IQR] age, 67.5 [60.8-74.0] years; 187 were male [56.3%], 27 were Black [8.7%], 33 were other races [10.7%], and 249 were White [80.6%]) and the nondurvalumab cohort included 137 patients (median (IQR) age, 70.0 [64.0-75.0] years; 89 [65.0%] were male, 11 [8.9%] were Black, 19 [15.4%] were other races, and 93 [75.6%] were White). Most patients had a smoking history (durvalumab, 316 patients [95.2%] and nondurvalumab, 132 patients [96.4%]) and Eastern Cooperative Oncology Group performance status 0 through 1 (durvalumab, 251 patients [90.9%] and nondurvalumab, 88 patients [81.5%]). Median (IQR) CRT duration was 1.6 (1.4-1.8) months for the durvalumab cohort and 1.5 (1.4-1.8) months for the nondurvalumab cohort. Median time to durvalumab discontinuation was 9.5 months (95% CI, 7.8-10.6 months). Median TFST and TTDM were not reached (NR) in the durvalumab cohort and 8.3 months (95% CI, 4.8-11.8 months) and 11.3 months (95% CI, 6.4-14.5 months), respectively, in the nondurvalumab cohort. Median PFS and OS were 17.5 months (95% CI, 13.6-24.8 months) and NR in the durvalumab cohort and 7.6 months (95% CI, 5.2-9.8 months) and 19.4 months (95% CI, 11.7-24.0 months) in the nondurvalumab cohort. In Cox regression analyses of patients who completed concurrent CRT without progression, durvalumab was associated with a lower risk of progression or death (hazard ratio [HR], 0.36; 95% CI, 0.26-0.51) and lower risk of death (HR, 0.27; 95% CI, 0.16-0.43), adjusted for prior platinum agent and patient characteristics.

Conclusions And Relevance: In this cohort study, findings were consistent with PACIFIC, and durvalumab was associated with a lower risk of progression and/or death. Further investigation is warranted to explain why patients did not receive durvalumab after its approval.