Glucagon-like peptide-1 receptor agonists (GLP-1RAs), like semaglutide, are widely used for managing diabetes and weight loss. However, their extended use raises concerns about their impact on immune responses, particularly vaccine efficacy. Unlike natural GLP-1, GLP-1RAs have longer half-lives and are administered at higher concentrations, potentially affecting immune cells beyond the pancreas. Research suggests that GLP-1RAs may modulate macrophage function and T lymphocyte responses, potentially altering how the body reacts to vaccines. Studies show that GLP-1RAs can skew macrophages toward an anti-inflammatory M2 phenotype, which might reduce immune cell activation and cytokine production, potentially weakening vaccine responses.

While GLP-1RAs influence immune cells like macrophages and T cells, their effects on vaccine responses are not fully understood. Evidence suggests immune suppression through pathways like cAMP and PKA, which can dampen immune activation. As GLP-1RAs gain wider use, especially in weight loss treatments, understanding their long-term impact on immune function and vaccination outcomes is crucial. Future research is needed to ensure that their growing adoption does not compromise vaccine efficacy.

Reference: van Niekerk G, Coelmont L, Alpizar YA, et al. GLP-1R agonist therapy and vaccine response: Neglected implications. Cytokine Growth Factor Rev. 2024;78:14-24. doi:10.1016/j.cytogfr.2024.07.006.