Long-Term Outcomes of Crizotinib Treated ALK-Positive Lung Cancer Patients: A Retrospective Audit of Prospective Data from Resource-Constrained Settings.

Akhil Kapoor  Crizotinib has been one of the standard treatment options for the treatment of anaplastic lymphoma kinase (ALK) rearranged non-small cell lung cancer (NSCLC) based on higher progression-free survival (PFS) and objective response rates in phase III clinical trials. However, real-world data about the long-term efficacy and toxicity of crizotinib is limited.  A retrospective analysis of all patients with ALK-positive NSCLC, treated with crizotinib between March 2014 and December 2016, was performed. The main outcomes measured were PFS, overall survival (OS), and adverse effects.  One hundred and eighty-eight patients treated with crizotinib during this period were included in this study. The median age was 50 years (range: 24-74) with a majority being males (73.2%) and 80.3% with a performance status of 0 to 1. The median duration of follow-up was 49.4 months (range: 3.4-86.3%). The median PFS of crizotinib was 17.3 months (95% confidence interval [CI], 13.0-21.6) and 12.8 months (95% CI, 8.1-17.6) when used in first line or subsequent lines, respectively. The median OS was 38.3 months (95% CI, 28.4-48.2). The patients who received crizotinib in the first line had a median OS of 45.5 months (95% CI, 29.6-61.4) as compared with 29.7 months (95% CI, 22.2-37.2) for those who received in subsequent line (hazard ratio, 0.6, 95% CI, 0.4-0.9, =0.022). The most common all grade toxicities include transaminitis, anemia, fatigue, and corrected QT prolongation.  This real-world study confirms the long-term beneficial effects of crizotinib in ALK rearranged NSCLC with favorable toxicity profile like that of the registration studies, in resource constrained settings.