Can we improve clinical trial design in Alzheimer’s disease? The participants point of view

AbstractBackgroundPivotal to clinical trial success is the recruitment and retention of participants. To improve both, it is important to know which trial features increase willingness to enroll and are appreciated by participants. We examined experiences of trial participants, and their suggestions on how to optimize clinical trial design.MethodIn this mixed‐methods study, we included participants via the Dutch Brain Research Center (11 different international sponsor‐initiated Alzheimer’s disease trials). An online study‐specific questionnaire was distributed among current and past participants addressing four topics; participant’s motives to enroll, experienced burden, preferred frequency of visits, and attitudes towards participation. Subsequently, we organized three focus groups to gain more in‐depth understanding of negative and positive aspects of trial design. Audio recordings from focus group interviews were transcribed verbatim and analysed by thematic content analysis by two independent raters.ResultsThe questionnaire was completed by 71 participants (age 69±6.5, 54% female, 19 cognitively normal, 19 Mild Cognitive Impairment (MCI), and 33 Alzheimer’s dementia). To benefit future generations was most frequently (34%) reported as a motive for enrolment, Figure 1. The lumbar puncture (40%) and memory assessments (15%) were most often experienced as being of high burden. The most frequently mentioned features to increase the likelihood and willingness to enroll were a low probability to get allocated to the placebo group (27%), and the possibility to obtain personal test results (21%). Negative trial experiences according to focus group participants (N=12, 8 cognitively normal, 4 MCI) included the themes ‘not obtaining their own results during or at the end of a clinical trial’ and ‘no follow up enquiries after participating in the trial’. Among the positive aspects were ‘professionalism’, ‘accuracy’ and ‘empathy of research staff’.ConclusionOur findings provide input for how priorities of participants can be used in clinical trial design to optimize recruitment and ensure trial success. Relevant factors include expectation management and careful planning of high burden assessments, provision of individual feedback and prioritizing professionalism and empathy throughout conduct of the trial. Thus selection of experienced and well‐equipped trial centres is a key component.