"Sanofi-GSK's vaccine is the first candidate to demonstrate efficacy in a placebo-controlled trial in an environment of high Omicron variant circulation," the firm, which is developing the vaccine jointly with Britain's GSK, said in a statement.

The new data supporting its booster vaccine will be submitted to regulatory authorities, Sanofi added, reiterating its plan to start marketing its jab later this year.

(Reporting by Tassilo Hummel; Editing by Clarence Fernandez)