Durvalumab After Chemoradiotherapy for Locally Advanced NSCLC: A Real-World Analysis Using a Nationwide Claims Database in Japan

Background Durvalumab consolidation therapy after chemoradiotherapy (CRT) for locally advanced non-small cell lung cancer (NSCLC) is an established standard of care. However, real-world data from claims databases, which capture a broad clinical landscape, are lacking in Asia. This study aimed to characterize real-world treatment patterns and clinical outcomes using a nationwide claims database in Japan. Patients and Methods Patients who received durvalumab after definitive CRT for NSCLC between 2018 and 2024 were identified from the DeSC database. Overall survival (OS) was estimated using the Kaplan–Meier method. Radiation pneumonitis requiring steroid treatment was estimated using the cumulative incidence function with death as a competing risk. Results A total of 1,439 patients were identified, and the median age was 73.6 years. The median durvalumab treatment duration was 5.3 months, and treatment completion rates (≥10 and ≥11 months) were 32.2% and 26.3%, respectively. The median OS was 48.4 months (95% CI: 42.1–57.4 months). The 12-month cumulative incidence of pneumonitis requiring steroid treatment was 19.4% (95% CI: 17.3–21.6%). In multivariable analysis, increasing age, shorter CRT-to-durvalumab interval, pre-existing pneumonitis diagnosis, and respiratory motion management fee were associated with increased pneumonitis risk, whereas the use of intensity-modulated radiotherapy was associated with reduced risk. Among 280 patients who developed pneumonitis, durvalumab rechallenge was administered in 37.5%. Conclusion In this nationwide claims database study, we characterized the clinical practice of CRT with durvalumab treatment and the clinical outcomes in Japan. These real-world findings from Asia complement existing evidence and may inform treatment optimization for durvalumab after CRT. MicroAbstract Using a nationwide Japanese claims database, we analyzed 1,439 patients who received durvalumab after chemoradiotherapy for locally advanced NSCLC. Median overall survival was 48.4 months and the 12-month cumulative incidence of radiation pneumonitis requiring steroids was 19.4%. Intensity-modulated radiotherapy was associated with reduced pneumonitis risk, and durvalumab rechallenge was administered in 37.5% of pneumonitis cases.