03:45 PM EST, 02/14/2025 (MT Newswires) -- Moderna ( MRNA ) said Friday its trial for a trivalent vaccine against norovirus is currently on hold by the US Food and Drug Administration after a single adverse event report of a close of Guillain-Barre syndrome.

Investigation of the adverse event is currently underway, according to the company.

Moderna ( MRNA ) said it expects the clinical hold will not impact the efficacy readout timeline for the northern hemisphere trial as enrollment has already been completed.

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