Real-World Use and Outcomes of ALK-Positive Crizotinib-Treated Metastatic NSCLC in US Community Oncology Practices: A Retrospective Observational Study.

Introduction: Around 3⁻5% of non-small cell lung cancers (NSCLC) are ALK-positive. Crizotinib was the first approved ALK inhibitor from clinical trials. However, there are less data on the utilization and patient outcomes associated with crizotinib in real-world clinical practice.
Methods: This was a retrospective, observational study of adult crizotinib-treated ALK-positive metastatic NSCLC patients who received treatment between 1 September 2011 and 31 October 2014, with follow up through 31 December 2015. Data were obtained via programmatic queries of the US Oncology Network/McKesson Specialty Health electronic health record database, supplemented with chart abstraction. Overall survival (OS) and time to treatment failure (TTF) were estimated from crizotinib initiation using the Kaplan⁻Meier (KM) method.
Results: Of the n = 199 ALK-positive crizotinib-treated patients meeting eligibility criteria, crizotinib was prescribed as first line (1 L) in n = 123 (61.8%). The majority (88.9%) had confirmed adenocarcinoma histology and 32.2% had brain metastases at initial diagnosis. Median age at crizotinib initiation was 60.2 years (range 27.1⁻88.2); 54.8% were never smokers, 33.7% were former smokers. Treatment of 250 mg, twice daily, was most commonly prescribed (89.5%) with the dose unchanged from an initial dose in 79.4% of patients. The primary discontinuation reason was progression ( n = 91, 58.7%). Patients (3.2%) were identified as discontinuing crizotinib as a result of treatment-related toxicity. With median follow-up time of 13.0 months (min⁻max = 0.03⁻46.6), median OS from crizotinib initiation was 33.8 months (95% CI = 24.3⁻38.8). Median TTF was 10.4 months.
Conclusions: Crizotinib usage evaluated within the real-world setting is consistent with prior phase III clinical trial data, and illustrates the real-world effectiveness of crizotinib.