Abstract
Influenza A and B infections cause significant morbidity and mortality. Over the past 30 years, two main influenza B strains have been circulating globally. The trivalent influenza vaccine used in the last 25 years contains one B strain, with approximately 31% of B strain disease coverage over the last 10 years. Fluarix quadrivalent vaccine, containing two A and two B strains, combines the components of two existing trivalent vaccines to prevent this mismatch. This review gives an overview of the published data about Fluarix quadrivalent vaccines, showing an immunogenicity and safety profile of the vaccine comparable with the two licensed trivalent vaccines containing the same strains, but with no evidence for efficacy in the literature. Future vaccines aim for a universal influenza vaccine that will give a long-lasting protection against all influenza strains.
Financial & competing interest disclosure
SN Faust is the UK Chief Investigator for GSK quadrivalent influenza vaccine trials QIV004 and QIV009 on behalf of his employing institutions (university and NHS Trust), but receives no personal payments. SN Faust has participated in advisory boards for vaccine manufacturers, with all honoraria being paid to the university or NHS Hospital accounts. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
Influenza causes significant morbidity and mortality.
Two influenza A and two influenza B strains have been circulating over the past 30 years.
Trivalent influenza vaccines contain both A strains and one B strain.
Quadrivalent influenza vaccines contain both A strains and both B strains.
Fluarix Quadrivalent vaccine shows non-inferior immunogenicity, reactogenicity and safety profile with respect to the same strains contained within the Fluarix Trivalent vaccine and equivalent immunogenicity, reactogenicity and safety profile with respect to the additional strain in the quadrivalent vaccine.
No efficacy data are available for Fluarix Quadrivalent vaccine.
Efficacy of inactivated influenza vaccines is, in general, suboptimal.
Future vaccines will aim for a universal influenza vaccine.