According to the first study results, the Covid-19 vaccine from Biontech and Pfizer, which has been adapted to Omikron, performed well against the highly contagious variant.

A booster vaccination with the partners' Omicron vaccine candidates triggered a significantly stronger immune response than the companies' original vaccine, Biontech and Pfizer announced on Saturday.

"We believe we have two very strong omicron-matched candidates," said Pfizer CEO Albert Bourla.

The two companies planned to bring an Omikron booster to market as soon as possible, if it is approved by the regulatory authorities.

The US Food and Drug Administration (FDA) is planning a meeting with outside experts next Tuesday to discuss the best composition for the fall booster vaccine.

According to the data, the booster, which was only adapted to the omicron variant BA.1, increased the number of virus-neutralizing antibodies by a factor of 13.5 at a dose of 30 micrograms and by a factor of 19.6 at a dose of 60 micrograms.

Another vaccine candidate, which is a combination of Biontech's original vaccine Comirnaty and a vaccine targeted against the BA.1 variant spike protein, resulted in a 9.1- and 10.9-fold increase, respectively.

The results come from a study of 1,234 people aged 56 and over.

The vaccinations were well tolerated by the participants.

The data suggest that both adapted omicron candidates neutralize the recently predominant BA.4 and BA.5 variants, albeit to a lesser extent than BA.1, the companies said.

Biontech and Pfizer want to collect more data on how well the boosters work against the variants that have been circulating lately.

The US biotech group Moderna had already published data on its omicron booster.

Accordingly, this also performed well against newer omicron subvariants and achieved a strong immune reaction.

Moderna plans to submit applications to regulators in the coming weeks to seek approval of the vaccine for the fall season.

Keywords: