08:50 AM EDT, 10/09/2025 (MT Newswires) -- Cidara Therapeutics ( CDTX ) said Thursday the US Food and Drug Administration has granted breakthrough therapy designation for its investigational flu prevention drug CD388 for adults and adolescents at high risk of flu complications due to weakened immune systems, poor vaccine response, or inability to receive vaccines.

The drug developer said the decision is based on a phase 2b trial that showed CD388 significantly reduced seasonal flu infections in healthy, unvaccinated adults aged 18 to 64.

A breakthrough therapy designation helps expedite the development and review of promising treatments for serious conditions, offering benefits such as priority review and closer FDA guidance, it added.

Shares of the company were up 3.5% in recent premarket activity Thursday.