Moderna announced that its cytomegalovirus (CMV) mRNA vaccine failed to meet primary efficacy endpoints in a Phase 3 trial and the company will stop most development of the program. The company disclosed low efficacy versus expectations and said it will reallocate resources across its pipeline. The failure removes what had been one of Moderna’s highest-profile post‑Covid commercial hopes and pressures the firm’s infectious-disease strategy. Analysts and company statements (Moderna press release; multiple STAT reports) cited efficacy in the single digits to low‑20s percent range, far below projections that had valued the asset as a potential blockbuster. Moderna’s leadership signaled disappointment and immediate program reprioritization while maintaining broader R&D investments in oncology and rare diseases. For the biotech sector, the outcome tightens scrutiny on mRNA applications beyond vaccines and raises questions about clinical translation timelines for next‑generation mRNA programs. Investors and partners will watch how Moderna shifts spend and whether learnings from the trial inform other mRNA candidates.