Access Consortium statement on authorisations of modified Covid-19 vaccines for variants

Future vaccine modifications that respond to new variants of coronavirus to be made available quickly to recipients, without compromising on safety, quality or efficacy


Authorised COVID-19 vaccines that are modified in response to new variants will not need “lengthy” clinical studies, according to new guidance from the Access Consortium – a coalition of regulatory authorities from Australia, Canada, Singapore, Switzerland and the United Kingdom. The guidance, developed by the MHRA in consultation with its Access Consortium partners, lays out what information the medicines regulators would need in order to approve any modifications to authorised COVID-19 vaccines, should virus mutations make them less effective at preventing the disease. This guidance adds to the earlier

According to the guidance, vaccine manufacturers would need to provide robust evidence that the modified vaccine produces an immune response.

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. This would significantly reduce the length of time taken for the modified vaccine to be ready for use.

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 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 consortium’s goal is to maximise international co-operation between partners in the consortium, reduce duplication, and increase each agency’s capacity to ensure patients have timely access to high quality, safe and effective therapeutic products.