Patients with Advanced Non–Small Cell Lung Cancer: Are Research Biopsies a Barrier to Participation in Clinical Trials?

Abstract

ObjectivesClinical trials of therapies for non–small cell lung cancer (NSCLC) are increasingly requiring mandatory tumor samples or research biopsies, both of which are potential barriers to trial participation. We assessed the impact of performance of research biopsies on the enrollment of patients with advanced NSCLC in clinical trials. MethodsThe cases of patients with advanced NSCLC who had been evaluated for clinical trials of systemic therapy at the Princess Margaret Cancer Centre from January 2007 to March 2015 were reviewed. ResultsOf the 55 clinical trials identified, 38 required tumor samples for enrollment. Six mandated repeat biopsies, whereas 32 permitted use of archival samples. Trial participation was offered to 636 patients at 940 unique study encounters, with some patients enrolling in multiple trials. Of the patients in 549 encounters during which participation in a therapeutic trial was offered, 60% received study treatment. More patients received study treatment (83% versus 55%, p < 0.0001) and study treatment was started earlier (after 9 days versus after 16, p = 0.002) when the trial did not have a mandatory tissue sample requirement. A similar trend was noted for trials permitting use of archival tissue versus mandatory repeat biopsies. The most common barriers to trial enrollment included absence of a required biomarker (34%), withdrawal of consent (20%), deterioration or death (17%), other exclusion criteria (15%), and insufficient biopsy tissue (10%). ConclusionA growing number of NSCLC trials are requiring tumor tissue for treatment eligibility, which appears to be a significant barrier to trial enrollment. Potential solutions include use of available diagnostic samples (e.g., cytology samples), development of peripheral blood assays for molecular markers, faster central laboratory testing turnaround time, and more resources for rapid biopsy.