FluGen’s Intranasal M2SR Flu Vaccine, Co-Administered with High Dose Vaccine, in Older Adults Shows Superiority Over Flu Shot Alone

Findings reported today in the journal Lancet Infectious Diseases
– Study shows synergistic immunological response generated by M2SR and Fluzone High Dose vaccine when used in combination in the highly vulnerable 65-85 years old population
– Results suggest approach could be used for vaccination against future influenza pandemics such as H5N1

MADISON, Wis., July 12, 2024 (GLOBE NEWSWIRE) -- FluGen, Inc., a clinical-stage vaccine company transforming vaccine efficacy in infectious respiratory diseases, today announced the results of its study comparing the coadministration of intranasal M2SR and the high dose flu shot in an unprecedented study of older adults ages 65-85 years. The findings are reported today in the journal Lancet Infectious Diseases (https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(24)00351-7/fulltext). The study evaluated the safety, tolerability, and immunological response to FluGen’s investigational supra-seasonal, live, single-replication, intranasal influenza (flu) vaccine when administered with Sanofi’s Fluzone High Dose inactivated influenza vaccine (IIV). There is a demonstrated unmet need for improved flu vaccine options, as current injectable vaccines primarily generate hemagglutinin (HA) antibodies and have shown only modest efficacy in most flu seasons. Funded by the U.S. Department of Defense (DOD), this study evaluated M2SR and Fluzone High Dose alone, and dosed concomitantly, in healthy adults 65-85 years of age, a population considered highly vulnerable to mortality from flu.

“Influenza continues to be a major cause of seasonal respiratory epidemics with significant morbidity and mortality, especially in older adults. Current vaccines fall short in three main areas – they don’t last long enough, they don’t protect against viruses that mutate and they don’t block the initial infection in the upper respiratory tract,” said Robert Belshe, MD, founder of Saint Louis University’s Center for Vaccine Development and recipient of the 2023 American College of Physicians James D. Bruce Memorial Award for Distinguished Contributions in Preventive Medicine “The results from this study represent a potential solution that might save millions of older adults from getting sick or worse.”

Intranasal vaccines are known to provide a wall of defense at the site of infection to help prevent influenza viruses from entering the nasal mucosa. Intranasal M2SR has shown the ability to elicit mucosal antibodies and also protect against drifted strains while being durable. Standard flu shots on the other hand, generate antibodies in the blood to help fight off the virus after it has already entered the body. Combining the benefits of both nasally delivered vaccines and the standard shot provide the best of both worlds.

The study demonstrated M2SR’s ability to statistically significantly raise mucosal antibodies in the nasal passages, serum antibodies against matched and drifted strains of the influenza virus, and cellular immune responses in subjects when compared to Fluzone High Dose and placebo. In a prior Phase 2 drifted H3N2 challenge trial, M2SR demonstrated efficacy against infection and illness across seven years of flu virus drift. Previous studies have also demonstrated that while currently licensed influenza vaccines administered by intramuscular injection generate tremendous antibody responses, only intranasal M2SR stimulates mucosal and cellular immunity as well as serum antibodies.

“The idea of delivering two vaccines in one sitting has become widely accepted,” said Paul Radspinner, President and Chief Executive Officer of FluGen. “Imagine being at your local pharmacy for your annual flu shot and also receiving a quick nasal spray that would greatly enhance your chances not only of becoming seriously ill but of being infected at all. This combination solution could have a tremendous impact on the health of older adults.”

Radspinner went on to discuss the possible impact on influenza pandemic protection. “If H5N1 or any other mutating influenza strain were to begin infecting millions of people as SARS-CoV-2 did, imagine the benefits of combining an intranasal vaccine, which could stop most infections from occurring, with a strong antibody-based vaccine shot. The impact on human health could be unequalled in our history.”

The randomized, double-blind, placebo-controlled Phase 1b study, entitled FluGen H3N2 v006 (ClinicalTrials.gov NCT05163847) was designed to evaluate a monovalent Cambodia 2020 H3N2 M2SR influenza A vaccine in a healthy, older adult population. The study enrolled over 300 subjects in four cohorts receiving either M2SR alone, high dose IIV alone, both vaccines concomitantly or placebo. The primary endpoint was to assess the safety and tolerability of a single dose of monovalent M2SR influenza vaccine delivered intranasally alone or concomitantly with high dose IIV delivered intramuscularly to healthy subjects 65 to 85 years of age. Secondary endpoints included evaluation of serum and mucosal antibody responses to matched and drifted strains of influenza virus following monovalent M2SR influenza vaccine delivered intranasally alone or concomitantly with high dose IIV delivered intramuscularly. Exploratory endpoints included evaluation of additional immune parameters such as T-cell responses.

This work was supported by The Assistant Secretary of Defense for Health Affairs endorsed by the Department of Defense, in the amount of ($11,439,843.00), through the Peer Reviewed Medical Research Program under Award Number (W81XWH-21-1-0563). Opinions, interpretations, conclusions, and recommendations are those of the author(s) and are not necessarily endorsed by The Assistant Secretary of Defense for Health Affairs endorsed by the Department of Defense.

About FluGen:

FluGen, Inc. is a clinical-stage vaccine company transforming vaccine efficacy in respiratory diseases. The company’s lead candidate is M2SR, a supra-seasonal, live, single-replication, intranasal flu vaccine. Unlike standard of care flu vaccines, M2SR stimulates mucosal, humoral, and cellular immunity. In an unprecedented human challenge trial, M2SR demonstrated protection against infection and illness across seven years of virus drift; and M2SR induces a durable antibody response with potential to cover an entire flu season and beyond. M2SR also has shown positive initial results as a vaccine vector for other respiratory vaccines and infectious diseases, including a COVID-19/flu combination and for RSV. For more information about FluGen, Inc., please visit http://www.FluGen.com/

CONTACT: Contact: Media – Paul V. Radspinner, 608-658-6095, pradspinner@flugen.com

MORE ON THIS TOPIC