Real world efficacy and toxicity of consolidation durvalumab following chemoradiotherapy in older Australian patients with unresectable stage III non-small cell lung cancer

Abstract

Introduction: Consolidation durvalumab following platinum-based chemoradiotherapy (CRT) significantly improved overall survival for patients with unresectable stage III non-small cell lung cancer (NSCLC) in the PACIFIC trial. However, older patients were underrepresented in PACIFIC, and subsequent analyses suggested trends toward poorer survival and increased toxicity in patients aged ?70 years old. We assessed the effectiveness and safety of consolidation durvalumab following CRT in older Australian patients with unresectable stage III NSCLC. Materials and Methods: This retrospective observational study was conducted across seven sites in Sydney, Australia between January 2018 and September 2021. All adult patients with unresectable stage III NSCLC who received platinum-based chemoradiotherapy followed by at least one cycle of consolidation durvalumab were included. Older patients were defined as being ?70 years old. Results: Of 152 patients included in the analysis, 42.8% (n = 67) patients were 70 years or older. Median follow-up was 26.1 months. The two-year overall survival and median PFS was similar between older and younger patients. At two years, 74.8% (95% confidence interval [CI]: 65.4?84.2%) of patients <70 years old and 65.2% (95% CI: 53.4?77.0%) of older patients were alive (p = 0.07; hazard ratio [HR] 1.64, 95% CI: 0.95?2.81). Median progression-free survival (PFS) in patients <70 years was 30.3 months (95% CI: 22.2?38.4 months) compared with 26.7 months (95% CI: 12.8?40.6 months) in older patients (p = 0.22; HR 1.46, 95% CI: 0.80?2.65). Toxicity was also similar, with 11.5% of patients <70 years old and 18.5% of older patients experiencing grade 3?4 adverse events (AEs; p = 0.23); 16.1% and 24.6% of the patients, respectively, discontinued treatment due to toxicity (p = 0.19). Grade 3?4 AEs and treatment discontinuation were associated with Charlson Comorbidity Index >5 (p = 0.011) and chronic obstructive pulmonary disease diagnosis at presentation (p = 0.002), respectively. Discussion: Older Australian patients receiving consolidation durvalumab following CRT experienced comparable outcomes to their younger peers. Comorbidity burden may be more important determinants of treatment tolerance than chronological age. � 2024 The Authors