FLU-IVIG was a randomized, double blind, placebo-controlled, multicenter, international clinical trial that sought to determine if when intravenous hyperimmune immunoglobulin (IVIG) was added to standard of care (SOC) treatment for individuals with influenza A or B, administration of IVIG was superior to placebo in terms of reducing disease severity and duration. This study started in Mexico on March 08, 2018 and closed on June 01, 2018 with an enrollment of 3 participants.