Eligibility of real-world patients with metastatic lung cancer for clinical trial participation: A population-based analysis.

Abstract

93 Background: Due to highly selective enrollment in clinical trials, the generalizability of results may be limited. This study aimed to identify the proportion of real-world patients with metastatic lung cancer (MLC) eligible to participate in a clinical trial. Methods: We identified patients diagnosed with MLC in a large Canadian province from 2004 to 2017. Ineligibility to participate in a clinical trial was defined by common exclusion criteria: age > 75 years, anemia, comorbid conditions (heart disease, uncontrolled diabetes, kidney disease, or liver disease) and history of a prior malignancy or immunosuppression. Logistic regression models were used to describe the likelihood of receiving systemic therapy and Cox regression models were constructed to determine the association of trial ineligibility with overall survival (OS). Results: A total of 13,996 patients were included; the median age was 70 years and 46.9% were women. Of these, 8,615 (61.6%) were trial-ineligible. The common reasons for ineligibility were age > 75 years (11.5%), abnormal renal function (8.3%) and prior immunosuppression (3.2%). Further, 32.3% of patients were ineligible by multiple exclusion criteria. In the real-world, 40.6% and 21.8% of trial-eligible and ineligible patients received systemic therapy (P < .001), respectively. After adjusting for age and sex, trial-ineligible patients had lower odds of receiving systemic therapy (odds ratio, .84; 95% confidence interval [CI], .76-.92; P < .001). At a median follow-up of 66.2 months, the median OS of trial-eligible patients was 5.1 months as compared to 2.9 months in those deemed ineligible (P < .001). Receipt of systemic therapy was associated with longer OS in both trial-eligible (10.5 vs 2.7 months, P < .001) and ineligible (9.3 vs 2.1 months, P < .001) patients. In a Cox regression model that adjusted for age, sex and systemic therapy, ineligibility was predictive of worse OS. Conclusions: More than half of patients with MLC are ineligible to participate in clinical trials. Real-world use of systemic therapy was generally low, but its use was associated with improvement in OS even among individuals considered trial-ineligible. Clinical trials should broaden their eligibility criteria to better represent the phenotype of real-world patients so that findings are more generalizable. [Table: see text]