Placebo-controlled disease endpoint trial data are the gold standard for authorizing vaccines. However, for COVID-19 vaccines, it is difficult to conduct efficacy trials in some countries, as few candidates are willing and available to participate. Without established humoral and/or cellular immune parameters that correlate to clinical protection against disease, other approaches are needed to provide sufficient evidence for authorizing new COVID-19 vaccines.
The International Coalition of Medicines Regulatory Authorities (ICMRA) convened a workshop on June 24, 2021, to consider the development of COVID-19 vaccines. The ICMRA focused on immunobridging, the design and use of controlled trials (placebo or other controls) and correlates of protection.
Access Consortium members agree that well-justified and appropriately designed immunobridging studies are an acceptable approach for authorizing COVID-19 vaccines.
For specific considerations and detailed requirements please refer to the complete statement (may be updated to take into account future developments).