Accelerated approval of H1N1 vaccine was based on immunogenicity seen with the seasonal vaccine.
CSL Biotherapies gained accelerated approval from the FDA for use of its seasonal flu vaccine, Afluria®, in children six months and older. The company’s influenza A (H1N1) 2009 monovalent vaccine was also cleared for active immunization in this younger age group.
The sanction of the H1N1 vaccine is based on the observed immune response elicited by Afluria and the fact that both vaccines are manufactured by the same process. There have been no controlled clinical studies demonstrating a decrease in influenza disease after vaccination with Afluria.
CSL’s H1N1 vaccine was licensed by the FDA for adults on September 15. It is a purified, inactivated, monovalent influenza virus propagated in embryonated chicken eggs. The vaccine is available in both thimerosal-free (i.e., preservative-free), single-dose, prefilled syringes and multidose vial, thimerosal-containing formulations.
CSL is conducting clinical trials in the U.S. with its monovalent H1N1 vaccine in children using a thimerosal-free formulation. The studies will evaluate the incidence of adverse events up to six months after first injection. The clinical studies are sponsored by CSL Biotherapies and funded in whole or in part with federal funds from the U.S. Office of the Assistant Secretary for Preparedness and Response, BARDA.
Thus far the FDA has sactioned H1N1 vaccines from Sanofi Pasteur, Novartis Vaccines and Diagnostics, and MedImmune. Sanofi Pasteur is the only other company that has won approval for use of its injectable vaccine in children over six months. Novartis’ injection is sanctioned for people four years and older, while MedImmune’s intranasal vaccine is indicated for individuals between two and 49 years of age.