US Government Orders 2M Doses of Avian Flu Vaccine

Early this week, the National Institute of Allergy and Infectious Diseases (NIAID, Bethesda, MD) announced it will order two million doses of an avian influenza vaccine from Sanofi-Pasteur (Swiftwater, PA and Lyon, France). In April, the NIAID began a Phase I trial to evaluate the vaccine’s safety and ability to generate immunity against the H5N1 strain of avian flu, an illness that leads to severe disease and possible death in birds and humans. The government also contracted with Chiron Corporation to manufacture 10,000 doses of similar vaccines, but production has not begun because of contamination found previously in its Liverpool plant (see D. McCormick, “Chiron Continues; Compounding Crackdown,” Pharm.Technol.29 (2), 17 (2005).

Though the first 115 volunteers of the study’s 450 subjects exhibited a strong immune response to the vaccine, NIAID’s director, Anthony S. Fauci, MD, cautioned in a recent New York Times article, “We don’t have all the vaccine we need to meet the possible demand. The critical issue now is, can we make enough vaccine, given the well-known inability of the vaccine industry to make enough vaccines.”

Mass production of flu vaccines has been a challenge for vaccine manufacturers because the supply of chicken eggs (in which the vaccine is made) is limited. To help speed production, the vaccine was developed by reverse genetics using a seed virus “for vaccine production in a matter of weeks, a process that usually requires several months,” Fauci said in an article he prepared for The Washington Times in March. The lack of manufacturing capacity is another problem that makes mass production difficult. According to Fauci, the vaccine maker will manufacture flu vaccine in shifts, with next winter’s flu vaccine production ending this month and the avian vaccine production beginning in mid-September at the earliest.

Studies will continue on the remaining 335 volunteers and additional tests are needed to determine the appropriate dosage of the vaccine and whether dose-sparing techniques can be used to stretch available supplies. Though the vaccine is not ready for use by the general public, the government plans to stockpile the vaccine and distribute doses in the event of a US pandemic.

–Kaylynn Chiarello