(Reuters) -Shares of French drugmaker Valneva slumped more than 20% on Monday after the U.S. Food and Drug Administration suspended the licence for its chikungunya vaccine, Ixchiq, with immediate effect,

U.S. health authorities have suspended the license for the Ixchiq vaccine against the chikungunya virus following reports of "serious adverse events", the drug's French maker said on Monday.

The US Food and Drug Administration (FDA) announced late last week that it has suspended the license for French drugmaker Valneva's chikungunya vaccine, saying that continued administration of the vaccine to the public would pose a danger to health.