The U.S. Food and Drug Administration approved four vaccines against the 2009 H1N1 influenza virus. The vaccines are made by CSL Limited, MedImmune LLC, Novartis Vaccines and Diagnostics Limited, and sanofi pasteur. All four firms manufacture the H1N1 vaccines using the same processes. Jesse Goodman, M.D., FDA acting chief scientist, commented, “The H1N1 vaccines approved today undergo the same rigorous FDA manufacturing oversight, product quality testing and lot release procedures that apply to seasonal influenza vaccines.” The FDA said that, as with the seasonal influenza vaccines, the 2009 H1N1 vaccines are being produced in formulations that contain thimerosal, a mercury-containing preservative, and in formulations that do not contain thimerosal.
http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm182399.htm