Fast track for variant-specific COVID-19 vaccines, say ACCESS regulators

The ACCESS Consortium says that its approach – based on that for seasonal flu vaccines - would significantly reduce the length of time taken for a modified vaccine to be assessed and authorized.

Variations in the SARS-CoV-2 spike protein – such as the UK, South Africa and Brazil variants – are a cause for concern because this is the target of most coronavirus vaccines. Vaccines may therefore need to be updated to better target these variants.

The ACCESS Consortium is made up of the UK’s MHRA, Health Canada, Swissmedic, Health Sciences Authority of Singapore and Australia’s Therapeutic Goods Administration: and aims maximise international collaboration and alignment of regulatory requirements in an increasingly globalised marketplace.

While developers can already test cross-reactivity of sera from vaccinated people with the new strain in relevant assays, a regulatory approach should be set out now in case modified vaccines are required, says the Consortium. The guidance is for vaccines but may also be relevant for other targeted therapies such as monoclonal antibodies.

“Vaccine manufacturers would need to provide robust evidence that the modified vaccine produces an immune response, but time-consuming clinical studies that do not add to the regulatory understanding of a vaccines safety, quality or effectiveness would not be needed,” ​notes the MHRA, commenting on the publication of the guidelines this month. “This is because researchers are now better able to measure protection by looking at antibodies in the blood following vaccination, reducing the need to wait and see whether or not people in a trial become infected with the disease.​

“Alongside data on the immune response, the vaccine manufacturer would also be expected to provide evidence showing the modified vaccine is safe and is of the expected quality. ​

“In addition, data from the original robust clinical trials and the ongoing studies on real-world use in millions of people could be used to support any decision by the regulators.  ​

“This approach is based on the tried and tested regulatory process used for seasonal flu vaccines, for which annual modifications are needed to match the strains circulating each year.”  ​

The ACCESS guidance can be found here​​. It follows the publication of guidance on variant-specific vaccines from the US FDA​​ and Europe’s EMA​​ over the last few weeks.