Safety and immunogenicity of a new influenza vaccine grown in mammalian cell culture

In a phase I safety and immunogenicity study, 112 healthy adult volunteers were randomly allocated to receive a new bivalent (A/Texas/36/91H1N1-like], B/Harbin/7/94) split virion influenza vaccine propagated in Madin-Darby Canine Kidney cell culture or an identical vaccine manufactured using currently licensed egg propagated virus technology. Soreness at the injection site was common but generally mild (75% of the cell culture-derived vaccine group and 62.5% of the egg-derived vaccine group; p = not significant). General reactions were less common; headache was the most frequently reported adverse effect (26.8 and 30.4%, respectively; p = not significant). Geometric mean haemagglutination inhibition titres post-immunization against the A/Texas strain were 1012 reciprocal dilution in the cell culture-derived vaccine group and 790 in the egg-derived vaccine group; against the B/Harbin strain titres were 420 and 447, respectively (all comparisons, p = not significant). It is concluded that the cell culture-derived split virion influenza vaccine is safe and immunogenic in healthy adult volunteers.