The present study is designed to evaluate the immunogenicity and safety of a single or double dose of the candidate vaccine in healthy elderly persons. The candidate vaccine will be administered following a two-administration schedule (21 days apart) in adults over 60 years of age. The persistence of H5N1 influenza antibodies will also be evaluated up to two years after vaccination (neutralizing antibodies will only be evaluated in a subset of subjects in the adjuvanted groups). Single and double dose of H5N1 vaccine non-adjuvanted vaccine will be used as comparator.