A double-blind, placebo-controlled, dose-escalation, phase 1 study was performed in 60 healthy subjects between 18 and 49 years of age. The two-dose regimen induced the development of neutralizing antibodies in high percentages of the subjects (from 88% to 100% of subjects depending on antigen content)”.

Due to an association that was observed in the United States between a swine-flu based human influenza vaccine developed in 1976 and the disease acute polyneuropathy Guillain-Barré syndrome (GBS) (1,2), GBS was one of the adverse events that was monitored in Europe and North  America (3) following the 2009 influenza pandemic vaccination campaigns.