Real-world treatment patterns and toxicity of durvalumab after chemoradiation in stage III non-small cell lung cancer.

e20109 Background: Durvalumab following concurrent chemoradiation is the standard of care for patients with unresectable stage III non-small cell lung cancer (NSCLC), based on the results of the PACIFIC trial. However, real-world populations often differ from clinical trial cohorts in terms of patient characteristics, treatment delivery, and toxicity. We aimed to describe real-world treatment patterns and safety of durvalumab in patients with stage III NSCLC treated at our institution. Methods: We conducted a retrospective, single-center cohort study including all patients with stage II–III NSCLC treated with concurrent chemoradiation followed by durvalumab between March 2018 and June 2024. Data collected included baseline clinical and tumor characteristics, chemotherapy and radiotherapy regimens, durvalumab treatment duration and discontinuation, and treatment-related adverse events. Results: A total of 102 patients were included, with a median age of 68 years; 55% were male and 95% had stage III disease. The predominant histologies were adenocarcinoma (71%) and squamous cell carcinoma (27%). A smoking history was present in 79% of patients. Most patients received platinum-based doublet chemotherapy concurrent with radiotherapy, most commonly cisplatin–etoposide (29%). Durvalumab was administered every 2 or 4 weeks according to institutional protocols. Overall, 47% of patients completed all planned durvalumab cycles. The most common reasons for treatment discontinuation were disease progression (53%) and treatment-related toxicity, with pneumonitis being the most frequent adverse event leading to discontinuation (38%). Durvalumab-related adverse events occurred in 45% of patients, with pneumonitis in 24% (25/102) and hypothyroidism in 12% (13/102) being the most frequent immune-related toxicities. Recurrence was predominantly intrathoracic (49%), with isolated brain recurrence in 23% and other extrathoracic recurrence in 6%. Hospitalization occurred in 33% of patients, with 75% due to non–treatment-related causes. Home care services were required in 20%. Median overall survival was 56 months (CI: 46-57.6) and median progression-free survival was 23 months (CI: 31.5-44.6). Conclusions: In this real-world cohort of patients with stage III NSCLC treated with chemoradiation followed by durvalumab, treatment completion rates were lower and toxicity rates higher than those reported in the PACIFIC trial. Immune-related adverse events—particularly pneumonitis—were common and frequently led to treatment discontinuation. These findings highlight the challenges of translating clinical trial results into routine practice and underscore the need for optimized toxicity monitoring and careful patient selection in real-world settings.