Alectinib and CNS Response in Resistant ALK-Positive Disease
The next-generation ALK inhibitor alectinib may prove to be an effective treatment of central nervous system (CNS) metastases in patients with ALK-positive non–small cell lung cancer (NSCLC) that is refractory to crizotinib, according to data from two pooled phase II studies. Leena Gandhi, MD, PhD, of New York University, Perlmutter Cancer Center, and colleagues presented these findings, which were obtained regardless of the assessment criteria used, in the European Journal of Cancer.
In both of these studies, baseline measurable CNS disease was identified in 50 patients by Response Evaluation Criteria in Solid Tumors (RECIST) and in 43 patients by Response Assessment in Neuro-Oncology High-Grade Glioma (RANO-HGG) criteria. The CNS objective response rate by RECIST was 64.0% and by RANO-HGG criteria was 53.5%. The investigators considered these CNS responses durable; the consistent estimate of median duration with RECIST was 10.8 months and with RANO-HGG criteria was 11.1 months.
A concordance rate of 92% was reported with the two assessment criteria used. A total of 3 of the 39 patients (8%) with measurable CNS disease by both assessment criteria had CNS progression according to one set of criteria but not the other.