Investigators Exploring Microneedle Patch As Universal Influenza Vaccine Candidate

Work to develop a universal flu vaccine using a microneedle patch will continue at Georgia State University’s Institute for Biomedical Sciences with a $3.86 million grant from the National Institutes of Health’s National Institute of Allergy and Infectious Diseases.

Baozhong Wang, PhD, associate professor and the grant recipient, said in a statement that the vaccine would protect against both influenza A and B viruses with double-layered, nanoparticle-sized clusters of proteins from both viruses and a molecular adjuvant administered using dissolvable painless microneedle patches.

“Benefiting from its dry formulation, this universal flu vaccine will be speedily disseminated without a cold-chain transportation requirement and be potentially administered by patients themselves," Wang said in the statement. "These qualities are critical in developing areas or a flu pandemic emergence.”

A previous investigation by Wang and his team generated double-layered protein nanoparticles (PNps) to provide protection against divergent influenza A viruses. It was based on an epitope named hemagglutinin (HA) stalk domain, which is highly conserved in various flu strains.

"In this study, we found that layered PNps composed of structure-stabilized HA stalk domains from both HA groups, and novel constructed M2e, are highly immunogenic to induce immune protection against homosubtypic and heterosubtypic influenza A virus challenges," the investigators wrote in the article published in the journal Nature Communications. "The double-layered PNps have the potentials to be developed into a universal influenza vaccine. The physiologically activated disassembly of PNps after the uptake into cells implies a wide utilization for protein drug delivery and controlled release."

The study elicited robust long-lasting immune responses in mice, demonstrating proof of concept of the universal influenza vaccine. The approach could be applied to other pathogens.

"We just finished the basic study in mice and wanted to move it to the ferret, which is closer to clinical trial," Ye Wang, a doctoral student at Georgia State University, and a member of the research team, told Contagion^®. "So far, we don’t know whether this novel nanoparticle will have similar protection pattern in ferrets (because the animal model changes), and we still need more funding to support our ongoing research."

The goal of the vaccine is to increase vaccine efficacy against all strains of the flu, Ye Wang said, noting that the vaccine used in the 2017-2018 flu season was only about 36% effective.

Improving the efficacy of the annual flu shot is an ongoing concern. During the 2017-2018 flu season, 42% of the population received a flu shot, and vaccines prevented an estimated 8000 deaths, according to a recent study.

"We want to rebuild the confidence for receiving the flu vaccine," Ye Wang told Contagion^®. "As a universal vaccine candidate, this novel nanoparticle vaccine will confer the protection against all strain of influenza virus."

By improving efficacy, the vaccine also could potentially reduce the use of drugs associated with influenza treatment. Investigators in Japan recently published findings that influenza viruses were exhibiting reduced susceptibility to a new influenza antiviral drug called Xofluza.