Nasal Spray Flu Vaccine Candidate Announced Positive Results

An intranasal vaccine candidate showed for the first time, protection against a highly mismatched influenza virus. 

FluGen Inc. said in a press release that despite the significant virus mismatch in this small study, more than 50 percent of the participants receiving the M2SR vaccine showed a serum antibody response to the vaccine. 

And, these subjects showed a 34 percent reduction of viral load during the challenge phase of the study, compared to placebo. 

This is a major step toward developing a universal flu vaccine. 

And, a second positive data point is this ‘nasal spray’ flu vaccine was effective. 

Historically, intranasal flu vaccines have not generated serum responses that have correlated with vaccine effectiveness in adults. 

In the ongoing phase 2 study, being conducted by SGS in Belgium, subjects were randomized 1:1 to receive either an intranasal placebo or a single intranasal dose of investigational M2SR vaccine, manufactured with the A/Brisbane/10/2007, H3N2 strain of influenza, which was utilized in marketed influenza vaccines during the 2008-2010 influenza seasons. 

Subjects were then challenged intranasally with the A/Belgium/4217/2015, H3N2 influenza virus, which is a genetically drifted virus that caused outbreaks of influenza in 2014-15. 

The topline results from a 6-year mismatch confirm the strong results seen in Phase 1 immunogenicity and preclinical challenge studies.   

According to the Centers for Disease Control and Prevention (CDC), in the 14 flu seasons since 2004, there have been 9 H3N2 vaccine changes (drifts), and in 3 of these seasons, the licensed inactivated vaccine was highly mismatched to the circulating virus. 

When the vaccine is mismatched and has low efficacy, the resulting toll includes increased hospitalizations and deaths from influenza. 

“The problem of seasonal drift and mismatches between the annual influenza vaccine and circulating strains is a significant public health challenge,” said Dr. Robert Belshe, chair of the FluGen clinical advisory board and the Diana and J. Joseph Adorjan Endowed Professor of Infectious Diseases and Immunology, Emeritus, at Saint Louis University, in a press release.  

FluGen plans to complete its data analysis and present the phase 2 data in an upcoming peer-reviewed forum, sometime in the second quarter of 2019. 

This study is supported by a $14.4 million grant from the Department of Defense. The U.S. Army Medical Research Acquisition Activity is the awarding and administering acquisition office and this work was supported by the Office of the Assistant Secretary of Defense for Health Affairs through the Peer Reviewed Medical Research Program under Award No. W81XWH-17-1-0430. 

The development of M2SR has also been supported by the National Institutes for Allergy and Infectious Diseases (NIAID) division of the National Institutes of Health (NIH). 

FluGen, Inc. is a clinical stage vaccine company focused on improving the breadth and effectiveness of influenza vaccines.