Pfizer and BioNTech have said a booster jab of their coronavirus vaccine promises to be an effective defence against the new Omicron variant.
After a small study the companies said three doses provide a similar level of antibodies against Omicron to that of two doses against other variants.
The World Health Organization (WHO) earlier said vaccines should still work against severe Omicron cases. Researchers across the world are piecing together data about Omicron.
It is the most heavily mutated version of coronavirus found so far.
In a statement, Pfizer chief executive Albert Bourla said protection against the variant would be improved with a third dose of the jab.
However, Pfizer and BioNTech noted that the results were preliminary and said they would continue to collect data and “evaluate real-world effectiveness”.