COVID-19 Vaccination

CLEO in the VACCELERATE Project
Center for Clinical Epidemiology and Outcomes Research – Greece

Overview of VACCELERATE
   • VACCELERATE is a pan-European clinical research network established to coordinate and conduct COVID-19 vaccine trials, especially phase 2 & 3. Vaccelerate+2EVI+2
   • It acts as a single entry point for stakeholders (academia, pharma, regulators, public health) in Europe. Vaccelerate+2PMC+2
   • Key elements include:
       ◦ Volunteer Registry for trial participants (> 107,000 volunteers across ~25 countries) Vaccelerate
       ◦ Site Network / capacity mapping of clinical trial and laboratory sites across Europe EVI+2PubMed+2
       ◦ Training, harmonization & quality management of trial protocols and lab assays PubMed+3Vaccelerate+3PMC+3
       ◦ Data standards, sharing & interoperability Vaccelerate+2ecrin.org+2
       ◦ Addressing underrepresented populations (children, pregnant women, immunocompromised, etc.) Vaccelerate+2PMC+2
   • Since its launch, the Site Network has grown significantly: as of April 2023, ~481 sites in 39 European countries are registered. PubMed
   • VACCELERATE also developed a harmonized set of promotional and educational materials (videos, brochures, interactive tools) to improve recruitment, inclusivity, and public understanding of vaccine trials. PubMed

Key Findings & Challenges from Research (Relevant to CLEO’s Work)
   • A study titled “The Challenges of Vaccine Trial Participation among Underserved and Hard-to-Reach Communities” (Poulimeneas et al.) surveyed 17 National Coordinators across the VACCELERATE network. PMC+1
       ◦ Underserved or hard-to-reach groups most frequently cited: ethnic minorities (76.5 %), persons experiencing homelessness (70.6 %), migrants/illegal workers/refugees (64.7 %) PubMed
       ◦ Main barriers: low health literacy, reluctance due to engagement burden, and low trust in vaccines/trials. PubMed
       ◦ National Coordinators prioritized outreach to migrants, immigrants, and ethnic groups. PubMed
   • In “Perspectives of European Patient Advocacy Groups on the VACCELERATE Volunteer Registry”(Zaoutis et al.), a survey of 520 members of patient advocacy groups revealed:
       ◦ Key decision factors for participating in trials: perceived risk, benefits, and quality & clarity of information. PubMed+1
       ◦ Northern European respondents were more likely to express willingness to enroll than Southern European respondents. PubMed
       ◦ Concerns included safety of novel vaccines and trust in those developing trials. PubMed+1
   • The “Design and Development of the Pan-European VACCELERATE” paper describes the creation of harmonized educational tools (videos, brochures, puzzles, etc.), designed for inclusiveness (especially for underserved groups). PubMed+1

CLEO’s Role & Added Contributions (Augmented with New Data)
   1. National Coordination for Greece
       ◦ CLEO continues to act as Greece’s official liaison in the VACCELERATE network, facilitating Greek trial sites' integration into the European infrastructure.
       ◦ Through this role, CLEO helps adapt promotional, training, and protocol tools to the Greek context and regulatory environment.
   2. Pediatric Trials & Special Populations
       ◦ CLEO’s leadership in mapping pediatric site capacities is aligned with VACCELERATE’s goals of including underrepresented populations (children, adolescents).
       ◦ The educational and promotional tools developed across VACCELERATE help inform potential participants about pediatric trial design, consent, and safety. PubMed
   3. Volunteer Engagement & Behavioral Research
       ◦ CLEO can leverage findings from the surveys described above (barriers, motivators) to refine local outreach strategies in Greece.
       ◦ The feedback from patient advocacy groups provides actionable insight for improving communication and building trust.
   4. Implementation of Educational & Promotional Tools
       ◦ CLEO may support translation, adaptation, distribution, and deployment of VACCELERATE’s harmonized materials (videos, brochures, interactive content) in Greece. PubMed
   5. Data & Site Network Participation
       ◦ As part of the European Site Network, Greek sites under CLEO’s purview contribute to capacity mapping efforts.
       ◦ CLEO can help ensure Greek trial sites adhere to VACCELERATE’s data standards, interoperability, and FAIR data principles.

Impact & Strategic Value
   • CLEO’s involvement strengthens Greece’s integration into Europe’s vaccine trial ecosystem, promoting equity, quality, and speed in vaccine research.
   • By combining behavioral insights, educational tools, and coordination mechanisms, CLEO contributes to overcoming barriers in trial enrollment, especially in hard-to-reach populations.
   • The infrastructure and experience built through VACCELERATE (even after EU funding ends) will support future pandemic preparedness and vaccine research beyond COVID-19. Vaccelerate+1