Barriers to patient enrolment in phase III cancer clinical trials: interviews with clinicians and pharmaceutical industry representatives

Objectives Phase III cancer clinical trials are expensive and time-consuming phases in drug development. Effective patient enrolment can reduce delays and save costs, offering patients an opportunity to benefit from innovative treatments. However, the current evidence base does not fully explain the persistence of barriers to patient enrolment in phase III cancer clinical trials. The aim was to explore clinicians' and pharmaceutical representatives' views on these barriers. Design A qualitative study was performed. In-depth information was collected from 15 experts in the field of oncology clinical trials, in particular clinical oncologists acting as principal investigators (PIs) and clinical research associates. By means of semistructured interviews, based on a questionnaire derived from our newly developed conceptual framework, they were asked to identify barriers to patient enrolment they had experienced and comment on barriers identified in literature. Findings Existing knowledge on barriers to patient enrolment was confirmed by all interviewees. Two new key barriers to patient enrolment were identified, that is, insufficient attention to the importance of clinical trial-based research in medical training and a trust gap between PIs and pharmaceutical representatives. A third important barrier was increasingly narrow patient inclusion criteria. Conclusions The success rate of patient enrolment in phase III cancer clinical trials highly depends on the clinicians' willingness to take part in clinical trials. Raising awareness of the importance of clinical trials in medical training and among practising oncologists is recommended. Furthermore, to reduce barriers to patient enrolment, it is essential that both clinicians and pharmaceutical representatives acknowledge each other's expertise, become acquainted with each other's procedures and regulations, and work on building trust relationships. Finally, in accordance with our key findings, we propose to add two new barriers to our newly developed conceptual framework; insufficient attention to clinical trial research in medical training and trust gap.