VIRUSMAXTM
Microbix is now seeking out-licensing partners. Please contact William. J. Gastle at william.gastle@microbix.com.
Influenza Vaccine Discussion
Influenza (the 'Flu') is a contagious respiratory illness caused by influenza viruses. Infection can result in illness ranging from mild to severe and life-threatening complications. An estimated 10% to 20% of U.S. residents get the flu each year: on average 114,000 people are hospitalized for flu-related complications and 36,000 Americans die each year from complications of flu. Influenza can cause localized epidemics or worldwide pandemics, during which rates of illness and death from influenza-related complications can increase dramatically.
Influenza viruses cause disease among all age groups. Rates of infection are highest among children, but rates of serious illness and death are highest among persons aged > 65 years and persons of any age who have medical conditions that place them at increased risk for complications from influenza.
Surveillance programs and immunization are the basis of limiting influenza outbreaks. The fundamental problem is that influenza viruses change their surface properties rapidly, hence immunity does not confer lasting protection. Each year, the World Health Organization (WHO) analyzes epidemiological data on the previous influenza season, and recommends specific influenza strains for inclusion in the trivalent vaccine. In the United States, a panel of experts on the Centers for Disease Control (CDC) Advisory Committee on Immunization Practices (ACIP) review the WHO recommendations and other epidemiological data and formally recommend vaccine strains to be used for the upcoming Flu season. Typically, two strains of Influenza (a strain each of H1N1 and H3N2 subtypes) and a single strain of Influenza B are chosen.
Current Production Complexities
The vast majority of influenza vaccine is produced in allantoic chamber of embryonated chicken eggs, which provide suitable yields for industrial-scale vaccine production. However, production capacity is finite, and not all strains of influenza have suitable growth properties in eggs. Alternate strains must sometimes be chosen which may not confer effective protection against emerging influenza strains, as was the case for the 2003-2004 influenza season. Current production methodology does not allow for rapid reaction to a widespread epidemic or emergent strain due to industrial limitations in capacity and implementation, and there would be significant benefits to process improvements that increase the robustness, flexibility, and capacity of production.
Cell culture has been considered an alternative for influenza vaccines, but this technique is proving extremely expensive to develop. Yield, and thus capacity, currently is relatively low compared to growth in embryonated eggs. In addition, vaccines produced from tissue culture are considered new and thus regulatory requirements include expensive and lengthy clinical trials. At best, implementing this strategy in a cost-competitive way relative to egg-based production makes this approach several years away even in the most optimistic outlook.
Microbix' Vaccine Technology Platform
Microbix has developed a proprietary technology that allows the current manufacturing process to increase capacity of flu production significantly, while concomitantly facilitating greater flexibility in the choice of virus strains.
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