Innovative strategies for human metapneumovirus vaccine development: A scoping review.

Abstract

Human metapneumovirus (hMPV) is a respiratory pathogen that infects people of all ages; however, it is predominantly associated with severe illness in infants, older adults, and immunocompromised individuals. There are still no licensed vaccines available for its prevention. This article summarizes recent advances in hMPV vaccine design through a systematic review using the Joanna Briggs Institute methodology. Searches were conducted in PubMed/MEDLINE, ScienceDirect, SciELO, and Dialnet from 2001 to November 2025. 43 preclinical and clinical studies focusing on attenuated viral vaccines, recombinant viral vectors, structural subunit formulations, and mRNA-based platforms were included. The studies included describe advances in stabilizing the F protein in its prefusion conformation. This protein is considered the primary protective antigen and the primary immunological target. Attenuated viral vaccines and recombinant vector vaccines have demonstrated favorable safety profiles and the induction of mucosal immunity in animal models and early clinical trials. mRNA platforms and virus-like particles elicit immunogenicity, consistently increasing neutralizing antibodies, and are well tolerated. The studies included indicate that structural vaccinology, alongside multivalent strategies, has contributed to the development of hMPV vaccine candidates. However, further clinical studies are needed to evaluate its efficacy, durability, and applicability in different populations.