Up to Twelve-Month Efficacy Against Influenza Observed; Good Protection Demonstrated in Trial Evaluating the Benefit of the Recommended Two Doses
for Previously Unvaccinated Children
HONOLULU, May 5 /PRNewswire/ -- Data from two new studies presented at the annual meeting of the Pediatric Academic Societies (PAS) demonstrate that FluMist(R) (Influenza Virus Vaccine Live, Intranasal) may offer children both durable protection against influenza, as well as significant protection for previously unvaccinated children who receive the recommended two-dose regimen approximately four weeks apart. In the efficacy trial evaluating one and two doses in previously unvaccinated children, protection was also observed among previously unvaccinated children who received only one dose of FluMist.
"These data add to the growing body of evidence that FluMist offers good protection against influenza for children eligible to receive it," commented Chris Ambrose, M.D., director, medical affairs. "We hope that this data will help support public health efforts to encourage parents to vaccinate their children each year as soon as vaccine is available and follow dosing recommendations to optimally protect children against this infectious disease."
FluMist is different from the flu shot in that it uses live, attenuated -- or weakened -- viruses within the vaccine to help stimulate an immune response that is designed to closely resemble the body's natural response to an influenza infection.
Efficacy of FluMist Among Previously Unvaccinated Children
In a study involving 3,200 previously unvaccinated children between the ages of six (1) and 36 months, the efficacy of one dose of FluMist was compared to the recommended two doses. The study showed that for children receiving one dose of FluMist, efficacy against matched strains was 58 percent, and efficacy increased to 74 percent for those receiving two doses. In the second season of the study, both groups received a single dose of FluMist (per recommendations) and no difference in efficacy was seen (efficacies of 65 percent and 74 percent, respectively). Runny nose/nasal congestion and cough were the most frequently reported events. No events were significantly increased in FluMist recipients; cough was significantly decreased. This double-blind, placebo controlled study, led by Drs. Bracco and Farhat of the Federal University of San Paulo, Brazil, was conducted at 35 sites in the Southern Hemisphere during the 2001 and 2002 influenza seasons.
Dr. Ambrose stated: "Previously unvaccinated children under nine years of age are recommended to receive two doses of influenza vaccine, but studies have shown that less than 50 percent of these children actually receive the second dose. Our trial shows clear evidence that receiving the second dose of FluMist provides more robust protection. However, we are also encouraged that there was still protection for those that received one dose."
Duration of Influenza Protection Using Nasal Spray Flu Vaccine
In a second study, researchers at MedImmune examined data from four previous clinical trials of children between six months (1) and 18 years of age and found that children who were given FluMist had a comparable level of protection through 12 months after vaccination.
"The data on FluMist's duration of protection provide comfort for providers and parents who wish to vaccinate children in late summer or early fall," said Ambrose.
FluMist is a live attenuated influenza virus vaccine indicated for active immunization of individuals two to 49 years of age against influenza disease caused by influenza virus subtypes A and type B contained in the vaccine.
FluMist is contraindicated in individuals with history of hypersensitivity to eggs, egg proteins, gentamicin, gelatin or arginine or with life-threatening reactions to previous influenza vaccinations, and in children and adolescents receiving concomitant aspirin or aspirin-containing therapy.
Do not administer FluMist to children less than two years of age due to an increased risk of hospitalization and wheezing that was observed in clinical trials. FluMist should not be administered to any individual with asthma and to children less than five years of age with recurrent wheezing unless the potential benefit outweighs the potential risk. Do not administer FluMist to individuals with severe asthma or active wheezing.
If Guillain-Barre syndrome has occurred with prior influenza vaccination or if an individual is immunocompromised, the decision to give FluMist should be based on careful consideration of the potential benefits and risks. FluMist should not be administered to individuals with underlying medical conditions predisposing them to wild-type influenza infection complications unless the potential benefit outweighs the potential risk. FluMist should be given to a pregnant woman only if clearly needed.
Most common adverse reactions (occurring in 10 percent or more of individuals receiving FluMist and at a rate at least five percent higher than in those receiving placebo) are runny nose or nasal congestion in recipients of all ages, fever more than 100 degree F in children two to six years of age, and sore throat in adults.
FluMist may not protect all individuals receiving the vaccine. FluMist is for intranasal administration only.
Please see complete Prescribing Information for FluMist, call 1-877-FLUMIST (1-877-358-6478) or visit http://www.flumist.com/prescribing-information.aspx for additional information.
MedImmune strives to provide better medicines to patients, new medical options for physicians and rewarding careers to employees. Dedicated to advancing science and medicine to help people live better lives, the company is focused on infection, oncology, respiratory disease and inflammation, cardiovascular/gastrointestinal disease, and neuroscience. With approximately 3,000 employees worldwide and headquarters in Maryland, MedImmune is wholly owned by AstraZeneca plc (LSE: AZN.L, NYSE: AZN). For more information, visit MedImmune's website at http://www.medimmune.com.
(1) Do not administer FluMist to children less than two years of age due
to an increased risk of hospitalization and wheezing observed in
Copyright©2008 PR Newswire.
All rights reserved