BRUSSELS: The European drugs regulator could shortly approve an amendment to its approval of the Pfizer-BioNTech COVID-19 vaccine that would permit the extraction of six doses from a vial instead of five, an EU official told Reuters on Wednesday.

The source, who asked to remain anonymous because discussions are not public, said the change to the authorisation could come "very soon".

The European Medicines Agency recommended on Dec. 21 the conditional approval of the Pfizer vaccine. Under that authorisation five doses should be extracted from each vial.