Abstract 202P
Background
The efficacy of consolidation durvalumab after dCRT for NSCLC patients with driver mutations, often associated with an immune-cold tumor microenvironment, remains uncertain. This study investigates its efficacy in NSCLC patients with driver mutations that have established first-line targeted therapies in advanced settings.
Methods
We conducted a retrospective analysis of de-identified data from 3 oncology centers in Hong Kong, including consecutive patients treated between January 1, 2019, and December 31, 2022. Eligible patients were diagnosed with histologically confirmed stage III unresectable NSCLC per AJCC 8th edition criteria, received a minimum of 54 Gy of radical radiotherapy, and at least 2 cycles of concurrent platinum-based chemotherapy. Patients were required to have one of the following actionable driver mutations: EGFR sensitizing mutations, ALK, ROS1 or RET rearrangements. The effect of durvalumab was analysed using log-rank test with stratification. The primary endpoint was real-world recurrence-free survival (rwRFS), estimated using Kaplan-Meier method.
Results
A total of 118 patients underwent chemoradiation, of which 33 had the specified driver mutations. The cohort predominantly consisted of female, non-smokers with adenocarcinoma histology, most diagnosed with stage IIIB disease. Overall, the addition of consolidation durvalumab after dCRT did not improve rwRFS (hazard ratio (HR) 0.852, 95% confidence interval (CI) 0.394–1.843, p=0.683). Notably, patients with ALK, ROS1 and RET rearrangements exhibited a significantly shorter median rwRFS of 6.9 months (95% CI 2.0–11.9 months) compared to 12.8 months (95% CI 9.1–16.4 months) for those with EGFR mutations (p=0.022), a result that remained significant after adjusting for durvalumab use. All patients with ALK, ROS and RET rearrangements experienced disease progression during durvalumab treatment.
Conclusions
Consolidation durvalumab after dCRT is ineffective for patients with actionable driver mutations. As consolidation targeted therapy emerge to become the standard of care for patients with EGFR mutations, future research should explore similar strategies for those with ALK, ROS1, and RET rearrangements.
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.