MF59: A safe and potent oil in water emulsion adjuvant for influenza vaccines, which induces enhanced protection against virus challenge

Abstract

In pre-clinical studies, MF59 adjuvant offered improved protection against influenza virus challenge and significantly reduced the viral load in the lungs of challenged mice. The ability of MF59 to be an effective adjuvant for influenza vaccine in mice was shown in old mice (18 months of age) and also in mice that had been previously infected with influenza virus, situations closer to those in which influenza vaccines are used in humans. In pre-clinical studies with an influenza vaccine derived from a mammalian cell culture source, rather than eggs, MF59 has been shown to be the most potent adjuvant available for both antibody and T cell responses, and is significantly more potent than aluminumbased adjuvants. In humans, MF59 is a safe and potent vaccine adjuvant that has been included in a licensed influenza vaccine for elderly subjects in more than 20 countries (Fluad®). After 10 years of use, with more than 35 million doses distributed, the safety profile of the MF59-adjuvanted vaccine is well established through a large safety database. MF59 adjuvant has a significant impact on the immunogenicity of flu vaccines in the elderly, and also in adults who are chronically ill, an additional population who may need an improved influenza vaccine. MF59 has also been shown to have a significant impact on the immunogenicity of pandemic influenza vaccines, allowing a significant reduction in the dose of vaccine administered. Importantly, MF59 allows for more broad crossreactivity against viral strains not included in the vaccine, for both seasonal and pandemic influenza vaccines. Moreover, the age range for which this adjuvant appears suitable can range from the elderly, down to very young children. Recent data establish the safety and potency of MF59 adjuvant in young children, in combination with influenza vaccine.