Prospective multicenter cohort study of durvalumab for patients with unresectable stage III non-small cell lung cancer and grade 1 radiation pneumonitis

Objective: Durvalumab was safe and effective in patients with unresectable stage III non-small cell lung cancer (NSCLC) after concurrent chemoradiotherapy (CCRT) in a phase 3 trial (PACIFIC trial). Although a history of radiation pneumonitis (RP) has been reported to increase the risk of exacerbation of pneumonitis associated with programmed death-1 axis inhibitors, the detailed clinical results of durvalumab treatment in patients with baseline grade 1 RP were not reported in the PACIFIC trial. Therefore, we aimed to evaluate the safety and effectiveness of durvalumab therapy in these patients. Materials and methods: This was a multicenter prospective cohort study involving 35 patients. Patients were eligible if they met the following criteria: inoperable stage III NSCLC, administration of durvalumab within 42 days after CCRT using platinum-based chemotherapy, no disease progression after CCRT, Eastern Cooperative Oncology Group performance status of 0-1, and presence of grade 1 RP at baseline. We assessed the effectiveness and safety of durvalumab with a minimum 1-year follow-up period for all patients. Results: Thirty-five patients were enrolled in our study from February 2019 to December 2019. The median progression-free survival was 11.4 months (95 % confidence interval, 7.1 months-not reached), and the median overall survival was not reached. Eleven (31 %) patients had grade >= 2 pneumonitis/RP, 10 (28 %) developed grade 2 pneumonitis/RP, and 1 (3 %) developed grade 5 pneumonitis/RP. Five (14 %) patients experienced treatment-related grade >= 3 adverse events. Conclusion: Durvalumab might be safe and effective in patients with stage III NSCLC with baseline grade 1 RP following chemoradiotherapy.