The European Medicines Agency (EMA) has started evaluation of the data on a booster (third) dose for the Covid-19 vaccine, Comirnaty, developed by Pfizer and BioNTech.
The move comes after the companies submitted a variation to the EMA requesting to update the conditional marketing authorization (CMA) with data supporting a booster dose of the vaccine.
This dose is intended to be given six months after the second dose in people aged 16 years and above.
Pfizer and BioNTech have submitted the same data to the US FDA. It is planned to be filed with other regulatory authorities in the upcoming weeks.
EMA’s Committee for Medicinal Products for Human Use (CHMP) will conduct an accelerated assessment of data submitted by the companies, including results from an ongoing clinical trial.
The submitted variation includes data from a Phase III clinical trial which enrolled 306 participants aged 18 to 55 and received a booster dose of Comirnaty between 4.8 and eight months after completing the two-dose primary regimen.
Median follow-up time was 2.6 months post-booster.
It was found that the third dose of the vaccine elicited significantly higher SARS-CoV-2 neutralising antibody titers against the wild-type strain compared to the levels that were observed after the two-dose primary series.
The companies also submitted Phase I data, which showed a similar pattern of booster responses against the wild-type strain, and the Beta and Delta variants.
Outcome of the CHMP’s evaluation is expected within the next few weeks and will be communicated by EMA.
Comirnaty, which is based on BioNTech’s messenger RNA (mRNA) technology, is currently authorised for use in people aged 12 and above.
It contains a mRNA molecule with instructions for producing the spike protein, naturally present in the SARS-CoV-2 virus. The vaccine prepares the body to defend itself against this virus.
EMA is also separately evaluating data from the literature on the use of an additional, third dose of an mRNA vaccine (Comirnaty or SpikeVax) in severely immunocompromised people.