JMIR Publications

ABSTRACT

Background:

Despite the vast growth of vaccine studies during the SARS-CoV-2 pandemic, clinical trials failed to represent diverse societal groups, including “underserved” or “hard-to-reach” groups. Understanding the factors hampering participation in vaccine clinical trials may facilitate better promotion of the VACCELERATE Volunteer Registry and enhance future access and engagement of volunteers in clinical trials.

Objective:

We aimed to decipher the causes of underrepresentation in vaccine trials by examining access mechanisms as experienced by professionals with expertise in vaccines/ vaccine trials.

Methods:

An online questionnaire was developed to gather personal information, group-specific barriers to vaccine trial participation and suggestions to overcome these barriers. Data are presented as absolute (n) and relative frequencies (%).

Results:

Hundred and fifteen respondents, the majority of whom were working in the scientific community (63.5%) completed the online survey. Challenges in recruiting children were identified due to “safety/efficacy concerns”, “difficulties about ethics and regulatory issues” and “lack of targeted information and communication”. Challenges in recruiting pregnant and lactating women (PLW) were primarily “ethics and regulatory requirements”, “safety issues” and “lack of prioritization/interest”. “Lack of information and communication channels adapted to the specific target group’’ along with “lack of prioritization” were the main challenges in recruiting older participants. Provision of health-related incentives including but not limited to access to new treatments and getting expert medical care seem to be the top-rated motivation to participate in vaccine clinical trials.

Conclusions:

The main challenges for recruiting PLW and children in vaccine trials involve safety and efficacy concerns, as well as the lengthy ethical and regulatory processes. For older adults, key issues include poor communication channels tailored to their needs, limited information, lack of prioritization, funding, infrastructure, and industry interest. Across all underrepresented groups, low awareness and poor communication about research opportunities were major barriers. Additionally, mobility issues affected older adults, while lack of motivation and incentives affected children, and low health literacy and provider uncertainty impacted PLW. Improving communication infrastructure and enhancing communication strategies with clear, tailored messages to build trust and motivate participation is essential to improve inclusion in vaccine research. Clinical Trial: Not applicable.