Early administration of durvalumab after chemoradiotherapy increased risk of pneumonitis in patients with locally advanced non-small cell lung cancer.

Aims: Durvalumab (Durva) administration after chemoradiation therapy (CRT) in locally advanced non-small-cell lung cancer (NSCLC) is the standard of care, associated with relatively prolonged progression-free (PFS) and overall survival. However, pneumonitis occurs in 73.6% of Japanese patients. This retrospective study aimed to identify factors associated with Durva efficacy and safety, specifically, the risk of pneumonitis.
Methods: This study included data from 26 consecutive patients with locally advanced NSCLC who underwent CRT followed by Durva. The rates of adverse events and PFS were examined.
Results: The median PFS time was 15.6 months (95% confidence interval [CI]: 8.7-not available). Patients developed pneumonitis of grade 1, 2, 3, and 4 at the rate of 62%, 27%, 12%, and 0%, respectively. The median PFS time was 6.4 months for patients with programmed death ligand 1 (PD-L1) expression level of <50% and not reached for patients with PD-L1 expression level of ≥50% (hazard ratio [HR], 0.19; 95% CI: 0.04-0.89), which was significantly prolonged. The cumulative incidence of pneumonitis grade 2 or above was significantly higher when the time between the last day of thoracic radiotherapy (TRT) and the start of Durva therapy was within 14 days compared to >14 days (HR: 0.19; 95% CI: 0.06-0.59). This association was statistically significant in multivariate analysis.
Conclusions: The initiation of Durva therapy within 14 days after TRT may increase the risk of pneumonitis grade 2 or above. Careful observation and suitable treatment are recommended.
(© 2022 John Wiley & Sons Australia, Ltd.)