FDA’s EUA benchmarks for COVID-19 vaccines remain ill-defined: GlobalData

Following the US FDA’s issuance of its guidance document, Reynald Castañeda, Pharma Writer for the Investigative News team at GlobalData, offers his view

“The US Food and Drug Administration’s (FDA’s) vaccine guidance mirrors the World Health Organization’s (WHO’s) prior statement on minimal prerequisites for approval, including at least 50 per cent protection, but the US agency’s comments on Emergency Use Authorization (EUA) benchmarks remain vague.

“While the FDA’s revocation of hydrochloroquine’s EUA after only three months could mean the agency may raise the bar for COVID-19 vaccines and require early protection data, the EUA process is also sensitive to political pressure, even if it is designed to be evidence-based.

“While National Institute of Allergy and Infectious Diseases Director Dr Anthony Fauci has said a vaccine is possible by the end of the year or early 2021, some interviewed experts differed. The burden of evidence for the vaccine’s risk-benefit profile and the company’s manufacturing capabilities suggests it would be tough to grant a vaccine any type of approval before year’s end, they noted. While there are ways to speed up data collection, they come with notable caveats.

“COVID-19 vaccines should ideally demonstrate an upsurge in both neutralising antibody titres and cell-mediated immunity to solidify their chances in offering durable protection. However, the front-runners only featuring the SARS-CoV-2 spike protein may not be enough to stimulate both responses, interviewed experts stressed.

“A hasty approval will likely hinder uptake, as the vaccine’s safety profile would be under the microscope, considering the vaccine’s adverse events would not be fully elucidated at the time of the EUA.

“An EUA could also have a negative ripple effect on COVID-19 vaccine development as a whole. Potential trial volunteers may opt to access the vaccine via the EUA rather than signing on to clinical trials. Additionally, future research may lean disproportionately towards the vaccine technology with an EUA rather than continued effort across multiple vaccine strategies.

“There are more than 100 COVID-19 vaccines in preclinical testing, according to GlobalData. Some 14 companies have moved their candidates into clinical trials but only AstraZeneca has an ongoing Phase II/III trial for its adenovirus-vectored vaccine, AZD1222, with a primary completion date of August 2021. Inovio and Moderna are two others to have announced Phase II/III plans for their respective assets, DNA plasmid vaccine INO-4800 and mRNA vaccine mRNA-1273.”