Recruitment and Retention in Clinical Trials of Deep Brain Stimulation in Early-Stage Parkinson's Disease: Past Experiences and Future Considerations.

Abstract

BACKGROUND:

Clinical trials are often hindered by inadequate patient recruitment. Overly optimistic investigator predictions of participation can lead to unmet recruitment goals and costly trial extensions. A patient-focused approach estimating recruitment in clinical trials may provide higher accuracy.

OBJECTIVE:

To assess the feasibility of recruitment in a future deep brain stimulation (DBS) in early-stage Parkinson's disease (PD) multicenter trial by understanding motivations and concerns to participation of past and potential future DBS in early-stage PD clinical trial subjects.

METHODS:

To identify motivating factors and barriers influencing trial participation, an end-of-trial survey was administered to subjects enrolled in a DBS in early-stage PD pilot trial with subjects randomized to receive DBS plus optimal drug therapy (DBS+ODT) or ODT alone (NCT#00282152, IDE#G050016). Pilot trial survey results were analyzed in conjunction with results of a previously-reported survey querying PD patients about potential participation in a trial for DBS in early-stage PD with similar inclusion/exclusion criteria.

RESULTS:

Pilot trial subjects reported high levels of satisfaction with their participation in the study. Similar motivations and barriers to participation were expressed in comparable proportions by subjects who successfully completed the pilot trial and patients with early-stage PD considering enrollment in a comparable DBS study.

CONCLUSIONS:

The FDA has approved a prospective, randomized, double-blind, phase III, multicenter, pivotal clinical trial evaluating DBS in early-stage PD (IDE#G050016). These results suggest that the successful recruitment and retention of early-stage PD subjects, as observed in the pilot trial, is attainable in a future pivotal trial.