Cidara Therapeutics announced positive mid-stage Phase 2b data for its long-acting antiviral biologic CD-388, designed to prevent seasonal influenza. The drug demonstrated 76% efficacy in preventing flu symptoms over 24 weeks in healthy adults aged 18 to 64. Well tolerated at all doses, CD-388 could become an alternative to conventional vaccines, potentially capturing a significant market opportunity. The company plans to engage with the FDA on Phase 3 trial design. These results come amid growing challenges with flu vaccines and demand for more effective prophylactics.