Objective: To investigate the immunogenicity of and tolerance towards the p
reservative-free inactivated influenza vaccine Begrivac(R). Methods: In thi
s prospective, single-centre, non-controlled study, efficacy was evaluated
by the change in influenza antibody titre from baseline to 21 days followin
g vaccination. The safety variables included post-injection reactions and a
dverse events. Blood samples were taken on day 21 and the antibody titre as
sayed by haemagglutination inhibition test. Results: All three of the Europ
ean efficacy requirements for influenza vaccines are satisfied by the new p
reservative-free vaccine described in this report. The mean geometric incre
ase in titre and the proportion of vaccination responders were greater in p
atients of the adult group than in the elderly. Thus for strain A/Beijing/2
62/95 66% of subjects seroconverted and 28% showed a significant increase i
n antibody titre (total 94%), compared to a total of 45 patients (76%) in t
he elderly group. For strain A/Sydney/5/97 the corresponding figures were t
otal 55 (90%) adult and 47 (80%) elderly, and for B/Beijing/184/93 46 (75%)
adult and 31 (53%) elderly. Sixty four subjects (53%) reported adverse eve
nts, mainly local reactions at the injection site such as pain, erythema an
d induration, and systemic reactions such as headache and fatigue. Conclusi
ons: The absence of preservative in this novel vaccine preparation does not
have any detectable impact on its efficacy or safety and tolerability prof
ile. (C) 2000 Elsevier Science B.V. All rights reserved.