Herpes Zoster mRNA Vaccine Candidate Offers Potent Cellular and Humoral Responses

Most older adults and immunocompromised individuals are familiar with herpes zoster (HZ), which causes painful rashes upon activating the varicella-zoster virus (VZV).

Although the U.S. FDA has approved a vaccine (Shingrix®) for preventing shingles, its administration is commonly associated with high reactogenicity.

On March 14, 2025, results from a new study published by the journal Nature focused on ten different vaccine candidate designs using two different codon optimizations targeting the VZV glycoprotein E (gE).

For this evaluation, researchers developed several VZV modRNA vaccine candidates targeting the glycoprotein gE, one of the most abundant proteins on the surface of the virion.

A subset of mRNA constructs was formulated into lipid nanoparticles and assessed for their ability to induce specific cellular and humoral immune responses in mice following vaccination.

Notably, the selected mRNA vaccine candidates induced high antibody levels and robust CD4+ and CD8+ immune responses.

Moreover, this study showed that alternate lyophilized vaccines provide comparable immunogenicity to liquid frozen formulations and are stable under long-term storage conditions.

Some of these investigational VZV modRNA candidates, including a lyophilized presentation, are currently being tested in a Phase I/II clinical study sponsored by Pfizer Inc.

This study's primary completion estimate is in late 2025.

While somewhat similar, no herpes simplex virus (HSV) vaccines are approved for use in 2025. However, this is an HSV mRNA vaccine candidate conducting research as of March 2025.