Time to response in patients with advanced anaplastic lymphoma kinase (ALK)-positive non-small-cell lung cancer (NSCLC) receiving alectinib in the phase ii NP28673 and NP28761 studies

Introduction: Alectinib is a highly selective and potent ALK inhibitor, approved for the treatment of patients with metastatic ALK+ NSCLC based on results from the Phase II global NP28673 (NCT01801111) and North American NP28761 (NCT01871805) studies. Methods: This exploratory analysis of two Phase II studies of alectinib (NP28673/ NP28761) investigated time to systemic response (TTR) and time to central nervous system (CNS) response (TTCR) in patients with previously treated advanced anaplastic lymphoma kinase fusion gene-positive (ALK+) non-small-cell lung cancer. Patients (n=225) received 600 mg oral alectinib twice daily and had scans every 6/8 weeks (NP28673/NP28761). Results: For NP28673 and NP28761, respectively: median follow-up was 21.3 months/17.0 months; most responders (72.6%/82.9%) responded by the first disease assessment; median TTR was 8 weeks (95% confidence interval [CI]: 8.00–8.14)/6 weeks (95% CI: 5.86–6.14); median TTCR in responders with measurable baseline CNS disease was 8 weeks (95% CI: 7.86–10.29)/6 weeks (95% CI: 5.71–not evaluable). Similar results were observed regardless of measurable/non-measurable disease. Discussion: These data suggest that alectinib achieves a rapid response in patients, both systemically and in the CNS.