Safety and effectiveness of alectinib in a real‐world surveillance study in patients with ALK‐positive non–small‐cell lung cancer in Japan

We conducted a large‐scale surveillance study as a post–marketing commitment to investigate the safety and effectiveness of alectinib in patients with ALK‐positive non–small‐cell lung cancer (NSCLC) in Japan. Patients receiving 300 mg twice‐daily alectinib (September 2014 to June 2015) were monitored until termination of alectinib or completion of 18 months of treatment at 519 Japanese study sites. The primary endpoint was the incidence of adverse drug reactions (ADR), which are important identified risks for alectinib in Japanese patients. Overall survival (OS), a key secondary endpoint, was assessed according to information on outcome. Overall, 1251 patients were enrolled. The median patient age was 62.0 years; 12.9% of patients were aged ≥75 years. At baseline, 63.0% of patients had received crizotinib and 40.6% had brain metastases. Altogether, 1512 ADR occurred in 654 patients (53.6%), with 164 grade ≥3 ADR in 123 patients (10.1%). Commonly occurring ADR were hepatic disorders (all grades, 19.8%; grade ≥3, 2.0%), decreased neutrophil and/or white blood cell count (all grades, 7.6%; grade ≥3, 1.1%), and interstitial lung disease (all grades, 3.8%; grade ≥3, .7%). Median OS was not estimable. The 18‐month cumulative OS rate was longer in patients with ECOG performance status ≤1 (vs 2 or ≥3; 83.7% vs 44.5% or 27.2%), without prior crizotinib (vs with; 81.1% vs 73.4%), receiving first‐line alectinib (vs second and third or later line; 83.0% vs 79.2% or 71.9%), without brain metastases (vs with; 79.5% vs 71.5%). These data confirm the favorable safety and effectiveness of alectinib in patients with ALK‐positive NSCLC in Japan.