Recent data showed that the investigational, egg-derived, monovalent, MF59-adjuvanted, seasonal influenza vaccine allowed reduced antigen content and promoted significant long-term antibody persistence among children aged 6 to 35 months.

Researchers randomly assigned 144 children, aged 6 to 11 months, and 186 children, aged 12 to 35 months, to vaccine formulations containing 3.75 mcg antigen with half of the standard dose of MF59 (Focetria, Novartis), 7.5 mcg antigen with a standard dose of MF59 or a non-adjuvanted formulation containing 15 mcg antigen (only administered to the older age group).

Study participants were given two primary vaccine doses 3 weeks apart, followed by one booster dose of MF59-adjuvanted seasonal influenza vaccine a year later. The study was conducted across 18 sites in Germany, Belgium, the Netherlands, the Dominican Republic and Chile between September 2009 and July 2011.

Among the younger age group, those who received full doses of MF59 had greater geometric mean titers compared with those who received half the standard dose, according to the researchers. One dose of either MF59 met the European Union’s Committee for Medicinal Products for Human Use criteria for geometric mean ration.

Among the older age group, full doses of MF59 induced greater geometric mean titers than half doses. Geometric mean titers were greater in response to both dosages of MF59 compared with the non-adjuvanted formulation.

All three vaccines met licensure criteria for geometric mean rations as early as 3 weeks after the first vaccination, according to the study results.