UPDATE 1-EU regulator begins review of Pfizer-BioNTech's variant-adapted COVID shot

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LONDON, Aug 9 (Reuters) - The European Medicines Agency (EMA) has started a rolling review of a variant-adapted COVID-19 vaccine from Pfizer and BioNTech, it said on Tuesday.

The so-called bivalent vaccine targets two strains of the SARS-CoV-2 virus behind COVID - the original strain first identified in China, and the Omicron offshoots BA.4/5 that are currently behind most cases in Europe.

A rolling review means the EMA assesses the data as it becomes available, and the process continues until there is enough data for a formal marketing application.

Last month, the EMA said it had begun a rolling review of another version of the companies' shot which targets the original SARS-CoV-2 strain and Omicron subvariant BA.1.

While existing coronavirus vaccines continue to provide good protection against hospitalisation and death, vaccine effectiveness has taken a hit as the virus has evolved.

European Union officials plan to use bivalent shots in their autumn vaccination campaign, with most cases in the region now linked to the BA.5 variant.

The EMA expects new COVID variant-adapted vaccines to be approved by September, but has signalled it is open to using shots targeting the older BA.1 variant for that campaign, given the shots targeting the newer BA.4 and BA.5 strains are further behind in clinical development. (Reporting by Natalie Grover in London Editing by Louise Heavens and Mark Potter)