FDA Approves H1N1 Flu Vaccines Produced in Eggs

The US Food and Drug Administration announced yesterday that it has approved four vaccines against the 2009(A)H1N1 ("swine") influenza virus. The vaccines will be distributed nationally after the initial lots become available, which is expected within the next four weeks.

The vaccines are made by CSL, Novartis Vaccines and Diagnostics, Sanofi Pasteur, and MedImmune. The vaccines made by the first three companies are all injections, whereas the MedImmune vaccine is administered as a nasal spray.

All four firms manufacture the H1N1 vaccines using the same egg-based processes, the traditional method of production for flu vaccines. Novartis, however, is also developing an adjuvanted H1N1 vaccine that is produced in cell culture. On September 3, Novartis announced the results of a pilot trial that demonstrated that its candidate adjuvanted cell culture-based vaccine elicited a strong immune response to A(H1N1).

Other companies, such as Baxter and Protein Sciences Corporation, are also developing influenza vaccines in cell culture for both pandemic and seasonal flu.

Based on preliminary data from adults participating in multiple clinical studies, the 2009 H1N1 vaccines induce a robust immune response in most healthy adults eight to 10 days after a single dose, as occurs with the seasonal influenza vaccine. Clinical studies under way will provide additional information about the optimal dose in children.

Potential side effects of the H1N1 vaccines are expected to be similar to those of seasonal flu vaccines. The FDA said it is working closely with governmental and nongovernmental organizations, including the Centers for Disease Control and Prevention, to enhance adverse event monitoring, information sharing, and analysis during and after the 2009 H1N1 vaccination program.

Vaccines against three seasonal virus strains are already available. http://www.flu.gov/seasonalflu/index.html

Previous coverage:Companies Race to Apply Cell Culture to Swine Flu Vaccines
July 9, 2009

Novavax Achieves Good Results for Vaccines Against Seasonal Flu and H1N1Sept 2, 2009

An Alternative to the Scale-up and Distribution of Pandemic Influenza VaccineJan 2, 2009