At the GP2 meeting, one of our interesting conversations was on overcoming barriers to Parkinson Disease trial participation. We tried to make sense of perceived barriers to trial participation to improve trial enrollment. Barriers to trial participation disproportionately affect some populations more than others. The impact of these barriers can affect the sex, age, racial, ethnic, socioeconomic, and geographic diversity of the patients included in studies. Generally, we all agreed underrepresented minorities, older patients, and patients with more medical comorbidities are underrepresented in research, and this can delay trial completion, exacerbate disparities, and limit our ability to generalize study results. Delays in trial completion result in delays in the review or potential approval of new drugs.
Efforts to improve trial design and recruitment are crucial to ensure study enrollment reflects the diversity of patients with PD.
Financial commitment and neuropsychological testing impact the retention of patients in a trial with follow-up. Recently,a patient was complaining about the amount of time spent in taking him through various questionnaires and screening tools when all he felt we needed was the sample for genetic analysis. We explained these additional scales and surveys were to make sense of the results from the genetic testing, but he was of the opinion that, the whole process was long and tedious.
Patients with more limited financial resources, including minorities and older adults may unlikely participate.
What can be done at the trial design level to broadening inclusion criteria? One major highlight was the lack of cultural input in trial designs. Interventions for targeted recruitment must include social marketing, community outreach, recruitment through the health system and referrals.
I was actually shocked to know that many non–English speaking patients are not even approached about clinical trial participation in the USA, despite high rates of enrollment when included.
Most genetic studies are largely conducted at limited academic medical centers, and most minority patients lack access to these centers. Limited geographic availability of trials can pose direct and indirect barriers to recruitment and trial participation- this is a major issue in Africa. Multisite consortium research such as PPMI are an excellent example and solution that increases access and the representation of subpopulations in clinical trials.
At the recruitment stage, increasing awareness, with traditional outreach or digital approaches; improving engagement, particularly with community physicians can also help improve enrollment of underrepresented patient populations.
The use of technology, for virtual visits can also reduce participant burden and increase recruitment. More frequent communication through telephone reminders and text messages about upcoming visits and eligibility screening, and financial incentives can increase trial recruitment.
What are your thoughts?