Is there a progression-free survival benefit of first-line crizotinib versus standard chemotherapy and second-line crizotinib in ALK-positive advanced lung adenocarcinoma? A retrospective study of Chinese patients.

Although crizotinib has demonstrated promising efficacy and acceptable toxicity in patients with advanced non-small cell lung cancer (NSCLC), the available evidence in Chinese populations is currently limited. This study compared the progression-free survival (PFS) of Chinese patients with anaplastic lymphoma kinase (ALK)-positive, advanced lung adenocarcinoma who received first-line crizotinib therapy with that of patients who received first-line standard chemotherapy, and also the PFS benefit of first-line versus second-line crizotinib treatment. Data on 80 patients with ALK-positive, advanced lung adenocarcinoma who received crizotinib or standard chemotherapy as first-line treatments between June 2013 and December 2014 were retrospectively collected; 26 of the patients received crizotinib as second-line therapy after progressive disease (PD) occurred on first-line chemotherapy. Tumor responses were assessed using Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1. The median PFS was 13.3 months (95% CI: 6.5-20.0 months) in patients who received first-line crizotinib as compared with 5.4 months (95% CI: 4.4-6.5 months) in patients who received first-line standard chemotherapy (adjusted hazard ratio for progression or death with crizotinib, 0.20; 95% CI: 0.11-0.36; P < 0.001). In patients who received second-line crizotinib therapy, the median PFS was 9.9 months (95% CI: 6.4-13.4 months). The difference between first-line and second-line crizotinib treatment was not statistically significant (adjusted hazard ratio for progression, 0.56; 95% CI: 0.29-1.11; P = 0.092). Thus, there was a significant PFS benefit of first-line crizotinib versus first-line standard chemotherapy in Chinese patients with ALK-positive lung adenocarcinoma. Additionally, crizotinib showed promising efficacy in patients who received it as second-line therapy after PD had occurred on first-line chemotherapy.