Modified vaccines to protect against new variants of coronavirus can be fast-tracked through the approval system, the UK’s independent medicines regulator said on Thursday.

The Medicines and Healthcare products Regulatory Agency (MHRA) said this is because authorised COVID-19 vaccines that are modified in response to new variants will not need a brand-new approval or ‘lengthy’ clinical studies, according to guidance from the Access Consortium –  a coalition of regulatory authorities from the UK, Australia, Canada, Singapore, and Switzerland.

The guidance, developed by the MHRA and Access, lays out what information the medicines regulators would need to approve any modifications to authorised COVID-19 vaccines, should virus mutations make them less effective at preventing the disease.

“Our priority is to get effective vaccines to the public in as short a time as possible, without compromising on safety. Should any modifications to authorised COVID-19 vaccines be necessary, this regulatory approach should help to do just that,” said Dr. Christian Schneider, MHRA Chief Scientific Officer.

“The announcement today also demonstrates the strength of our international partnerships with other regulators and how our global work can help ensure faster access to life-saving vaccines in the UK and around the world. The public should be confident that no vaccine would be approved unless the expected high standards of safety, quality and effectiveness are met,” he said.

The approach will be 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.

According to the latest guidance, 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 vaccine safety, quality or effectiveness would not be needed.

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, the MHRA explained.

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 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.

The MHRA joined the Access Consortium in October last year to be part of a worldwide effort is to maximise international cooperation 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.

Currently, the Brazilian variant of coronavirus, first detected in the city of Manaus, is causing the greatest concern over whether the current vaccines being administered will work to protect against it. Scientists have said that the current vaccines, especially those involving mRNA gene-based technology such as Pfizer/BioNTech, are relatively simple to reconfigure and adapt if required.