Real-World Treatment Patterns and Outcomes Across Three Lines of Therapy in Patients with ALK plus NSCLC

Introduction: Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) are standard first- and second-line treatment for advanced ALK+ non-small cell lung cancer (NSCLC). We evaluated outcomes in patients with ALK+ NSCLC receiving third-line ALK TKI versus non-ALK-directed therapy. Methods: Flatiron Health OncoEMR data were extracted for patients with ALK+ NSCLC initiating first-line ALK TKI between January 2015 and March 2022 followed by second-line ALK TKI and third-line ALK TKI (group A) or non-TKI therapy (group B). Time-to-treatment discontinuation (TTD) and overall survival (OS) were analyzed using multivariate modelling. Results: Among patients receiving third-line ALK TKI (A, n = 85) or non-TKI therapy (B, n = 43), most received first-line crizotinib (A/B: 64%/60%) and second-line alectinib (36%/30%), ceritinib (24%/19%), or lorlatinib (15%/30%). Common third-line treatments were lorlatinib/alectinib (41%/33%) in A and immunotherapy, chemotherapy, or chemotherapy + immunotherapy (30%/28%/21%) in B. Group A versus B had longer TTD of first-line treatment (hazard ratio [HR] 0.62, 95% confidence interval [CI] 0.41-0.93; p = 0.020) and second-line treatment (HR 0.50, 95% CI 0.33-0.75; p < 0.001) and longer OS from start of first-line treatment (HR 0.32, 95% CI 0.19-0.54; p < 0.001) and second-line treatment (HR 0.40, 95% CI 0.24-0.66; p < 0.001). For third-line treatment, median TTD (A/B) was 6.2/2.4 months (HR 0.61, 95% CI 0.37-1.00; p = 0.049) and OS was 17.6/6.5 months (HR 0.57, 95% CI 0.33-0.98; p = 0.042). Conclusions: Patients receiving third-line non-ALK-directed therapy had suboptimal outcomes on prior TKIs. Patients with longer duration of prior ALK TKI treatment appeared to benefit from third-line ALK TKIs. [GRAPHICS] .