Updated vaccines against Covid generate strong response against variant, say Moderna and Pfizer – 06/09/2023 – Health

Moderna and rival Pfizer announced on Wednesday that their updated Covid-19 vaccines, in tests, generated strong responses against the highly mutated subvariant BA.2.86 of the coronavirus, responsible for concerns about the resurgence of infections. .

Moderna reported that its vaccine elicited an 8.7-fold increase in neutralizing antibodies against BA.2.86 compared to the natural response of untreated antibodies in human clinical trials.

The variant is currently monitored by the World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC).

“We think this is news that people will want to hear as they prepare to receive their booster shots,” Jacqueline Miller, Moderna’s head of infectious diseases, said in an interview, adding that the data should also help reassure regulators.

Pfizer said its updated vaccine, in partnership with BioNTech, elicited a strong antibody response against BA.2.86 in a preclinical study in mice.

Moderna, Pfizer/BioNTech and Covid-19 vaccine market newcomer Novavax have been creating versions of their vaccines targeting the XBB.1.5 subvariant, dominant for most of 2023, which are expected to be released in the fall. of the Northern Hemisphere.

The CDC has previously indicated that BA.2.86 may be more capable of causing infections in people who have previously contracted the virus or been vaccinated with previous doses.

The omicron variant has more than 35 mutations in key parts of the virus compared to XBB.1.5, the target of updated vaccines.

The BA.2.86 subvariant has already been detected in Switzerland and South Africa, as well as in Israel, Denmark, the United States and the United Kingdom, according to a WHO official.

While it is important to monitor the variant, several experts told Reuters it is unlikely to cause a wave of serious illness and death as immune defenses have been built around the world through mass vaccinations and past infections.

(Additional reporting by Michael Erman in New Jersey)