As the frontrunners in the race to develop a COVID-19 vaccine, such as Moderna and AstraZeneca, reach late-stage trials, the US Food and Drug Administration (FDA) makes public its requirements on the efficacy for an approved product.
The guidance states that the primary efficacy endpoint estimate should be at least 50%, with a lower bound under 30%, but greater than 0%, acceptable as a statistical success criterion for a secondary efficacy endpoint.
Regarding the safety evaluation of any product that was able to prove efficacy and then receive approval, the agency noted that there might be ‘limitations’ on data accrued from clinical studies for a COVID-19 vaccine.
As a result, the FDA recommends early planning of pharmacovigilance activities prior to approval. Following potential approval, manufacturers will also have to submit reports of adverse events at more frequent intervals than is routine.
FDA commissioner, Stephen Hahn, acknowledged that the expedited regulatory process that could see a COVID-19 vaccine rapidly approved necessitated reassurance to the public that the agency’s decision-making process was “based on the science and the available data”.
“While the FDA is committed to expediting this work, we will not cut corners in our decisions and are making clear through this guidance what data should be submitted to meet our regulatory standards. This is particularly important, as we know that some people are skeptical of vaccine development efforts,” Hahn stated.
Once approved, the agency will recommend that manufacturers follow-up with study participants for as long as feasibly possible, ‘ideally’ for at least one or two years.
Clinical trial diversity
The FDA also called on drugmakers to include ‘diverse populations’ in clinical trials testing potential vaccines. The agency called to attention those populations most affected by COVID-19, specifically racial and ethnic minorities.
The agency specifically mentioned the inclusion of elderly individuals or those with medical comorbidities for late-stage trial representation as well, with these groups being particularly vulnerable during the pandemic.