FluMist ready for 2006-2007 flu season

Nasal-spray flu vaccine FluMist will be available for commercial sale by mid-September.

MedImmune, Inc. announced today that the U.S. FDA (Food and Drug Administration) has approved the distribution of FluMist for the 2006-2007 flu season. The FluMist, a live, attenuated influenza vaccine (LAIV), is approved for use in healthy individuals between 5 to 49 years of age. According to a Q&A from the CDC (Center for Disease Control) the vaccine grows only in the nose and throat, but not in the lower respiratory tract, and will not cause severe symptoms often associated with the influenza illness.

How effective is the nasal-spray flu vaccine (LAIV)?

• In one large study among children aged 15-85 months, the nasal-spray flu vaccine (LAIV) reduced the chance of influenza illness by 92% compared with placebo. In a study among adults, the participants were not specifically tested for influenza. However, the study found 19% fewer severe febrile respiratory tract illnesses, 24% fewer respiratory tract illnesses with fever, 23-27% fewer days of illness, 13-28% fewer lost work days, 15-41% fewer health care provider visits, and 43-47% less use of antibiotics compared with placebo.

• FluMist is a comprehensive immunization option because the vaccine has been shown to provide protection against drifted strains of influenza.(*) Each year, three strains for the seasonal influenza vaccine are chosen in advance of the influenza season. “Vaccine mismatch” occurs when the predominant circulating strains do not match those in the vaccine. Significant vaccine mismatch has occurred in four of the last eight influenza seasons. Studies of FluMist have indicated that the vaccine protected against matched and mismatched strains.

Because FluMist is a nasal spray instead of an injection, it was supposed to encourage vaccinations by people who didn’t like to get stuck with needles. However, it turned out to be more expensive than the injectable vaccine, and had to be kept frozen during storage which was cumbersome. MedImmune recently applied and was approved for a “new generation liquid” vaccine that only need refrigeration, and the company is also seeking approval to expand use to children ageds 6 months to 59 years. The company plans to market the new liquid vaccine during the 2007-08 season to people as young as 12 months.

* Belshe RB, Gruber WC, Mendelman PM, et al. Efficacy of vaccination with live attenuated, cold-adapted, trivalent, intranasal influenza virus vaccine against a variant (A/Sydney) not contained in the vaccine. J Pediatrics. 2000b;136: 168-175.

[News Source: Yahoo News]