EU regulator issues guidance to adapt COVID-19 vaccines to new variants

The European Medicines Agency has published guidelines for manufacturers of coronavirus vaccines planning to adapt already authorized vaccines to new variants.

The EU regulator says the three licensed vaccines, manufactured by Pfizer, Moderna and AstraZeneca, “provide protection against variants which are currently prevalent across Europe.”

“However, it appears that as mutations continue and new variants emerge, licensed vaccines may need to be adapted, in time to ensure continued protection.”

The variant that is of most concern at the moment is the one that first appeared in South Africa because of evidence that it can decrease the effectiveness of vaccines. The so-called British and Brazilian variants are also spreading rapidly.

The EMA says its experts have been working on the hypothesis that the adjusted vaccine would work the same as the original vaccine, except for a change in the part that triggers the body’s immune response.

He says that “large-scale safety and efficacy studies are not necessary,” but at least one clinical trial is recommended in people who have not been vaccinated or infected with the coronavirus.

The agency also suggested a study involving a small group randomly selected to receive either the parent vaccine or the variant vaccine to make sure they both elicit similar immune responses.

He says studies on the use of modified vaccines as a variant-protecting booster vaccine should be conducted, and he expects manufacturers to provide data on the quality of production of the adjusted vaccines.

Pfizer studies the 3rd vaccine vaccine

The new direction comes as Pfizer has started to investigate whether a third dose of its COVID-19 vaccine could offer protection against mutated versions of the virus, the company said Thursday.

The pharmaceutical giant said it would offer a third dose to 144 volunteers among participants in preliminary testing of the vaccine in the United States last year.

He wants to determine if an additional booster shot given six to 12 months after the first two doses would stimulate the immune system enough to ward off a mutated virus.

“While we have not seen any evidence that the circulating variants result in a loss of protection provided by our vaccine, we are taking several steps to act decisively and be prepared in the event that a strain becomes resistant to the protection offered by the vaccine. vaccine, ”Pfizer CEO Albert Bourla said in a press release.

“This booster study is essential for understanding the safety of a third dose and immunity against circulating strains,” he added.

Pharmaceutical giants working on updated recipes

At the same time, Pfizer and its German partner, BioNTech, are also refining their vaccine recipe.

The companies said they were in discussions with US and EU regulators regarding a “study to evaluate a variant-specific vaccine with an altered mRNA sequence. This study would use a novel Pfizer-BioNTech vaccine construct based on the line B.1.351, first identified in South Africa. “

Pfizer competitor Moderna already announced on Wednesday that it was ready to test experimental doses of its vaccine that better match the South African variant of the virus.

Pfizer and Moderna’s coronavirus vaccines use so-called mRNA technology that is easy to update. Their vaccines use a piece of genetic code for the spike protein that covers the virus, so the immune system can learn to recognize and fight the real thing.

If a variant with a mutated spike protein arises that the original vaccine cannot recognize, companies would trade that piece of genetic code for a better match – if and when regulators so decide.

But tweaking other coronavirus vaccines could be more complex. AstraZeneca’s shot, for example, uses a harmless version of a cold virus to carry this spike protein gene around the body. An update would require the growth of the common cold virus with the updated spike gene.

The US regulator said studies on the updated COVID-19 vaccines should not be as large or lengthy as for the first generation of vaccines. Instead, a few hundred volunteers could be given experimental doses of a modified vaccine, to see if their immune systems respond the same to the updated photo as they did to the original.