Randomised, multicentre, phase III, open-label study of alectinib vs crizotinib in treatment-naïve anaplastic lymphoma kinase (ALK)-positive advanced NSCLC (ALEX study).

Background: In ∼5% of advanced NSCLC tumours, ALK tyrosine kinase is constitutively activated after translocation of ALK. ALK+ NSCLC was shown to be highly sensitive to the first approved ALK inhibitor, crizotinib. However, all pts eventually relapse on crizotinib mainly due to secondary ALK mutations/amplification or CNS metastases. Alectinib is a highly selective, potent, oral next-generation ALK inhibitor. Clinical phase II alectinib data in 46 crizotinib-naïve pts with ALK+ NSCLC reported an objective response rate (ORR) of 93.5% and a 1-year progression-free rate of 83% (95% CI: 68-92) (Inoue et al. J Thorac Oncol 2013). CNS activity was seen: of 14 pts with baseline brain metastasis, 11 had prior CNS radiation, 9 of these experienced CNS and systemic PFS of >12 months; of the 3 pts without prior CNS radiation, 2 were >15 months progression free. Trial design: Randomised, multicentre, phase III, open-label study in pts with treatment-naïve ALK+ advanced, recurrent, or metastatic NSCLC. All pts must provide pretreatment tumour tissue to confirm ALK rearrangement (by IHC). Pts (∼286 from ∼180 centres, ∼30 countries worldwide) will be randomised to alectinib (600mg oral bid, with food) or crizotinib (250mg oral bid, with/without food) until disease progression (PD), unacceptable toxicity, withdrawal of consent, or death. Stratification factors are: ECOG PS (0/1 vs 2), race (Asian vs non-Asian), baseline CNS metastases (yes vs no). Primary endpoint: PFS by investigators (RECIST v1.1). Secondary endpoints: PFS by Independent Review Committee (IRC); ORR; duration of response; OS; safety; pharmacokinetics; quality of life. Additionally, time to CNS progression will be evaluated (MRI) for the first time in a prospective randomised NSCLC trial as a secondary endpoint. Pts with isolated asymptomatic CNS progression will be allowed to continue treatment beyond documented progression until systemic PD and/or symptomatic CNS progression, according to investigator opinion. Time to CNS progression will be retrospectively assessed by the IRC using two separate criteria, RECIST and RANO. Further details: ClinicalTrials.gov (NCT02075840). Disclosure: T.S.K. Mok: Advisory boards: AZ, Roche, Eli Lilly, Merck Serono, Eisai, BMS, AVEO, Pfizer, Taiho, Boehringer Ingelheim, Novartis, GSK Biologicals, Clovis Oncology, Amgen, Janssen, BioMarin; board of directors: IASLC; corporate sponsored research: AZ; M. Perol: Advisory boards: Roche; S.I. Ou: Consulting: Pfizer, Chugai, Genentech Speaker Bureau: Pfizer, Genentech, Boehringer Ingelheim; I. Bara: Employee: F. Hoffmann-La Roche Ltd; V. Henschel: Employee and stock: F. Hoffmann-La Roche Ltd.; D.R. Camidge: Honoraria: Roche/Genentech. All other authors have declared no conflicts of interest.