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Vaccines Working Group
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Accelerate the evaluation of vaccine candidates by supporting harmonized clinical efficacy trials and a parallel effort to generate biomarkers and other evidence for more rapid approval/authorization. The working group officially completed its charge as of July 31, 2020, but continues to meet on an ad-hoc basis to provide recommendations for ongoing vaccine trials.
Check mark indicates completion.
✓ Vaccine Clinical Trials
The working group coordinated and contributed to the development of harmonized protocols for vaccine evaluation in Phase 3 trials, which importantly allows for the simultaneous assessment of multiple vaccine candidates and the incorporation of new vaccines as they are available. Trials informed by the harmonized protocol for current Phase 3 vaccine studies and for future vaccine candidates are listed on the ACTIV Vaccines page.
✓ Human Challenge Studies
The working group published a Perspective for the New England Journal of Medicine that assess practical considerations and prerequisites for using controlled human infection models (CHIMs), which can be used for human challenge studies, to support SARS-CoV-2 vaccine development. They conclude that conventional randomized controlled trials involving only natural exposure to SARS-CoV-2 are the fastest and most effective path forward for establishing vaccine safety and efficacy. Parallel development of CHIMs may provide complementary tools to address additional questions such as the duration of immunity and correlates of protection, if such studies can be conducted ethically.
✓ Protective Immune Responses
At the beginning the ACTIV, it was unclear whether there would be sufficient disease incidence in the second half of 2020 to enable expeditious clinical evaluation of vaccine efficacy. To prepare for that contingency, the working group discussed potential interim data packages before Phase 3 efficacy results to enable possible authorization/approval through mechanisms like FDA accelerated approval or Emergency Use Authorization. During the course of the program it became clear that incidence rates in some regions of the world have remained high, enabling relatively rapid clinical evaluation of efficacy. The working group also has contributed to plans for analyses of correlates of protection to enable the approval of future vaccines based on biomarker established through efficacy trials.
Vaccine-Associated Immune Enhancement
The working group has submitted a scientific paper for publication that provides an informed perspective on the historical experience with vaccine-associated enhanced disease (through immunopathologies and antibody-dependent enhancement) and the question of potential vaccine-associated enhanced disease in COVID-19 vaccine development.
This page last reviewed on September 11, 2020