Seqirus announced the U.S. FDA has approved Audenz (Influenza A (H5N1) Monovalent Vaccine, Adjuvanted) to help protect individuals six months of age and older against influenza A (H5N1). Audenz is the first-ever adjuvanted, cell-based influenza vaccine designed to protect against influenza A (H5N1) in the event of a pandemic.
Seqirus presented data at the Options for the Control of Influenza (OPTIONS X) Conference in Singapore in August of 2019. The data are from clinical studies demonstrating the ability of a MF59 adjuvanted influenza vaccine to increase immune responses when used in both seasonal and pandemic influenza vaccines, across pediatric and adult populations. In the pediatric Phase II study (V89_11), a total of 322 subjects aged 6 months through 17 years received full doses of a MF59 adjuvanted, cell-derived influenza A (H5N1) vaccine (aH5N1c) three weeks apart. In two separate but similar adult and elderly Phase II studies (V89_13; V89_04), a total of 975 subjects aged 18 to 64 years of age and 1,388 subjects 65 years of age and older were equally randomized to received two full or half doses of a MF59 adjuvanted, cell-derived influenza A (H5N1) vaccine (aH5N1c) three weeks apart. A full dose was 7.5 μg HA of H5N1 with 0.25 mL MF59 for a total injection volume of 0.5 mL, and a half-dose was 3.75 μg HA of H5N1 with 0.125 mL MF59 for a total injection volume of 0.25 mL.
Antibody responses against five pre-determined H5N1 clades were measured by hemagglutination inhibition (HI) and microneutralization (MN) assays in pre-defined exploratory analyses. Adult and elderly subjects that received the full dose demonstrated increased immunogenicity against heterologous A (H5N1) strains from five different clades. Pediatric subjects that received the full dose demonstrated increased immunogenicity against heterologous A (H5N1) strains.
The U.S. FDA granted Fast Track designation for the aH5N1c vaccine for prevention of illness related to pandemic influenza caused by A (H5N1) virus in December 2015.
About Pandemic Influenza
Pandemic influenza, as with seasonal influenza, is a contagious airborne respiratory disease which is unpredictable and can occur in any age group or any population worldwide. The risk of influenza-associated morbidity and mortality is greater with pandemic influenza than with seasonal influenza because of little or no pre-existing immunity to the virus in the human population. Four influenza pandemics have occurred over the past century, with the 1918 pandemic being the most severe in recent history, estimated to have killed up to 50 million people worldwide. According to the World Health Organization (WHO), A (H5N1) influenza strain can cause severe disease and has a high mortality rate. If the A (H5N1) virus were to change and become easily transmissible from person to person while retaining its capacity to cause severe disease, the consequences for public health could be very serious, with an approximate 60% mortality rate.
Audenz (Influenza A (H5N1) Monovalent Vaccine, Adjuvanted) is a pandemic influenza vaccine developed by Seqirus. This is the first and only adjuvanted, cell-based pandemic vaccine to provide active immunization against the influenza A virus H5N1 strain. Seqirus has combined two leading-edge technologies—MF59 adjuvant and cell-based antigen manufacturing—to create this pandemic influenza vaccine.