mRNA Universal Flu Shot Candidate Begins Clinical Trial

A clinical trial of an experimental universal influenza vaccine candidate developed by researchers at the National Institute of Allergy and Infectious Diseases’ (NIAID) Vaccine Research Center (VRC) has begun enrolling volunteers.

This Phase 1 trial will test the experimental vaccine, known as H1ssF-3928 mRNA-LNP, for safety and its ability to induce an immune response.

“A universal influenza vaccine would be a major public health achievement and could eliminate the need for both annual development of seasonal influenza vaccines, as well as the need for patients to get a flu shot each year,” said Acting NIAID Director Hugh Auchincloss, M.D., in a press release on May 15, 2023. 

“Moreover, some strains of the influenza virus have significant pandemic potential. A universal flu vaccine could serve as an important line of defense against the spread of a future flu pandemic.”

A similar vaccine developed by researchers at NIAID’s VRC has already shown positive results in early clinical trials.

Both vaccines use a specific portion of a flu protein, hemagglutinin (HA), to induce a broad immune response against influenza.

While one portion of the HA protein, known as the head, tends to change as the flu virus spreads and evolves, a more stable portion, known as the stem, evolves very slowly and is very similar across many different types of the flu virus.

Researchers hope to induce long-term immunity against a broad range of flu viruses by using the HA stem as the basis for a vaccine.

Unlike the VRC’s earlier vaccine, the H1ssF-3928 mRNA-LNP vaccine candidate uses an mRNA platform.

By developing and testing various platforms for a universal flu vaccine, researchers are more likely to find one that is safe and provides strong and broad immunity against various strains.

Additional flu shot and influenza vaccine development news is posted at Precision Vaccinations.