Alectinib versus crizotinib in previously untreated ALK-positive advanced non-small cell lung cancer: final overall survival analysis of the phase III ALEX study

BACKGROUND: ALEX, a global, randomized, phase III trial evaluated alectinib versus crizotinib in patients with advanced ALK-positive non-small cell lung cancer (NSCLC). This final analysis provides mature overall survival (OS), duration of response (DOR) and long-term safety data. PATIENTS AND METHODS: Treatment-naïve patients with stage III/IV ALK-positive NSCLC were randomly assigned to receive alectinib [600 mg twice daily (b.i.d.)] or crizotinib (250 mg b.i.d.) until disease progression, unacceptable toxicity, withdrawal, or death. Primary endpoint was investigator-assessed progression-free survival (previously reported). Key secondary endpoints included OS, DOR and safety. RESULTS: A total of 303 patients (alectinib, n = 152; crizotinib, n = 151) were enrolled. At the updated data cut-off (28 April 2025), after a median follow-up of 53.5 (alectinib) and 23.3 (crizotinib) months, median OS was 81.1 [95% confidence interval (CI) 62.3 months-not estimable] versus 54.2 (95% CI 34.6-75.6 months) months, respectively [hazard ratio (HR) 0.78; 95% CI 0.56-1.08]. Improvement in median OS was observed with alectinib in patients with and without central nervous system (CNS) metastases at baseline [with CNS metastases: 63.4 (n = 59) versus 30.9 (n = 53) months with alectinib versus crizotinib, respectively (HR 0.68; 95% CI 0.40-1.15); without CNS metastases: 94.0 (n = 93) versus 69.8 (n = 98) months (HR 0.87; 95% CI 0.58-1.32)]. Median DOR in confirmed responders was longer with alectinib (42.3 months, 95% CI 31.3-51.3 months) versus crizotinib [11.1 months, 95% CI 7.9-13.0 months (HR 0.41; 95% CI 0.30-0.56)]. Long-term safety (median duration of alectinib treatment, 28.1 months) remained consistent with earlier reports, with no new or unexpected safety concerns identified. CONCLUSIONS: These final OS data show the sustained long-term systemic and intracranial efficacy of alectinib in the first-line treatment of ALK-positive NSCLC and confirm alectinib as a standard of care in this setting.