Abstract
BACKGROUND: The current standard treatment for limited-stage small cell lung cancer (LS-SCLC) is concurrent chemoradiotherapy (cCRT) plus consolidation immunotherapy, with or without prophylactic cranial irradiation (PCI). However, it remains unknown whether administering immunotherapy concurrently with chemoradiotherapy confers additional benefit. This clinical trial is designed to investigate the efficacy and safety using durvalumab with chemoradiotherapy for LS-SCLC. METHODS: In this single-arm phase 2 study, patients with LS-SCLC received three (1-4) cycles of etoposide, cisplatin, or carboplatin, and durvalumab every 3 weeks, following by thoracic radiotherapy of 60.0 Gy to the gross tumor volume and 54.0 Gy to the planning target volume in 30 once-daily fractions and chemoimmunotherapy. After cCRT plus durvalumab, patients received durvalumab consolidation therapy every 3 weeks for a minimum of 1 year. PCI was recommended to patients with partial or complete response when chemoradiotherapy completed. Efficacy and adverse events were assessed. RESULTS: Overall, 51 patients were enrolled from March 1, 2021, to April 30, 2024, with a median follow-up of 32.0 months. The 1-, 2-, and 3-year progression-free survival (PFS) rates were 56.9%, 35.9%, and 28.2%, respectively, and the median PFS was 17.0 months. The 1-, 2-, and 3-year overall survival (OS) rates were 88.1%, 68.6%, and 49.6%, respectively, and the median OS was 32.0 months. There were 17 (33.4%) patients with grade 3 or 4 adverse events, 7 of which were immune‑related. CONCLUSIONS: These results suggest that the addition of durvalumab to chemoradiotherapy was well tolerated and showed encouraging efficacy, supporting further investigation in patients with LS-SCLC eligible for radical chemoradiotherapy.