Versatope CEO Discusses Company's Progress on Universal Flu Vaccine

With flu season rapidly approaching, many people across the United States are rushing out to get their flu shots in hopes that this year’s vaccination will mitigate chances of coming down with “the crud.”

While the flu vaccine is highly recommended by physicians and other healthcare professionals, the once-per-season injection does not provide protection against all flu strains. Globally, there are about 650,000 deaths from the flu worldwide and millions of people are hospitalized due to the illness. According to the U.S. Centers for Disease Control and Prevention, flu vaccines were about 29% effective in 2018 due to the emergence of new strains. There have been efforts to develop universal flu vaccines, but so far nothing has been approved. Earlier this year, the National Institutes of Health (NIH) began its own program aimed at developing a universal vaccine that is currently enrolling in a Phase I trial. According to the NIH, the experimental vaccine known as H1ssF_3928 is designed to “teach the body to make protective immune responses against diverse influenza subtypes by focusing the immune system on a portion of the virus that varies relatively little from strain to strain.”

Massachusetts-based Versatope Therapeutics received a leg up in its universal vaccine development efforts at the end of September with a $17.9 million grant from the National institute of Allergy & Infectious Diseases (NIAID).

In September, NIAID, a division of the NIH, awarded the grant over five years to help the company advance its vaccine program. Versatope is focused on developing a vaccine comprised of extracellular bacterial vesicles to provide protection against all strains of flu. Christopher Locher, chief executive officer of Versatope, told BioSpace that the vaccine asset under development relies on an “ion channel, the matrix 2 protein or M2, expressed predominantly on the surface of the virus infected cell.” This is an important distinction, Locher said, as most vaccines are genetic-type specific.

“Our vaccine candidate doesn’t adjust to changes in viral strains like most commercial influenza vaccines,” Locher told BioSpace. Rather, M2 induces antibodies that mediate antibody dependent cellular cytotoxicity that target and kill virus-infected cells with the help of natural killer cells, peripheral blood mononuclear cells and macrophages, he added.

Locher noted that there are numerous limitations in commercially-available flu vaccines, inactivated viral vaccines, due to their design. “Current vaccines are only moderately effective and sometimes the strain recommendation does not match circulating viruses. As a result, the average effectiveness of the current flu vaccine was found to be less than 50% over the last 13 years,” he said.

Versatope’s universal vaccine candidate addresses these limitations, Locher said, because the company’s M2-based vaccine focuses the immune response “on a relatively more genetically-conserved protein than H or N.” In preclinical development, Versatope’s asset is based on a technology from Cornell University using a recombinant outer membrane vesicles (rOMV) derived from genetically engineered and detoxified E. coli, whose outer surface mimics the cell from which it originate, Locher said.

While the vaccine is still in preclinical development, Locher said Versatope hopes to develop a vaccine that is safe and well-tolerated for all age groups. When the candidate was being studied at Cornell, the research showed that mice infected with influenza A virus developed high levels of antibodies just four weeks after vaccination. That was in comparison to eight weeks from a standard flu vaccine. The data also showed that the effect was long-lived. After six months, all of the test mice given the OMV vaccine survived a lethal influenza A infection, Cornell reported. The data Locher provided indicated that the life expectancy of a mouse is only about six months, which means that the vaccine stuck with the animals through the course of their life. It’s thought that this indicates the vaccine could last for many years in people, something that human trials could eventually show.

Versatope Therapeutics launched in 2017 with a focus on the development of an immunotherapy platform using recombinant vesicles from probiotic bacteria, such as the rOMVs. OMVs are protein, lipid, and polysaccharide-based vesicles that are produced in a constitutive fashion from the outer membrane and periplasmic space of Gram-negative bacteria, Locher said.

If all goes well, Versatope will push its vaccine candidate into human trials and could potentially be available to the public by 2026.