Efficacy
FluMist® starts working where flu typically starts — in the nose — to help stimulate a natural immune response.1,2
Since influenza strains change year to year, past clinical trial results are not indicative of future results.
Scroll down to see full Important Safety Information.
Efficacy in Adults
Adult Effectiveness Study: Reductions in Influenza-like Illness (ILI) vs. Placebo1,5
In healthy adults ≤49 years of age, FluMist was substantially effective in reducing cases of influenza-like illness (ILI).
Reduction of ILI vs. placebo in a multicenter, randomized, double-blind, placebo-controlled trial in 3,637 adults (FluMist n=2,411, placebo n=1,226) 18 through 49 years of age during the 7-week, site-specific outbreak period during the 1997-1998 influenza season. Results based on illness signs and symptoms; enrollees not tested specifically for influenza.
Flu vaccine effectiveness was not demonstrated in a subgroup of adults 50 years to 64 years of age.
Challenge Study: Efficacy in Preventing Influenza vs. Placebo6
Prevention of laboratory-documented influenza vs. placebo in a multicenter, randomized, double-blind, placebo-controlled trial in 60 healthy adults (FluMist n=29, placebo n=31) 18 years to 41 years of age who were challenged with wild-type virus during the 1995-1996 influenza season.
Efficacy in Children
Overall Efficacy in Children Aged 24 to 59 Months During 2004-2005 Influenza Season (FluMist vs. Flu Shot)1-3*
In a large, head-to-head influenza vaccine trial in children published in the New England Journal of Medicine, FluMist demonstrated a 54% reduction in influenza cases versus the flu shot.1-3†
In the same study:
- Children receiving the flu shot were 2 times more likely to get the flu than those who received FluMist.1-3
- FluMist demonstrated similar results against mismatched strains.1-3
Full study published in the New England Journal of Medicine — February 2007.
* Study Design: Randomized, double-blind, double-dummy comparison of the relative efficacy of FluMist and TIV intramuscular injection that included children 24 months to 59 months of age, with a 42-day and a 6-month follow-up for safety through the end of the influenza surveillance period for the 2004-2005 influenza season (N=4,166). Vaccine-naive children in both groups received 2 doses. Comparative efficacy vs. culture-confirmed modified CDC influenza-like illness due to matched and mismatched strains [ATP population].
† Data is representative of the indicated population: full study population is represented in the Prescribing Information
‡ The attack rates for FluMist vs. the flu shot for all strains circulating during the 2004-2005 flu season were as follows: A/New Caledonia (H1N1) (0.0% vs. 1.0%), A/Wyoming (H3N2) (0% vs. 0%), A/California-like (H3N2) (1.2% vs. 4.9%), matched B/Yamagata lineage (1.4% vs. 1.9%, NS), and mismatched B/Yamagata lineage and B/Victoria (2.1% vs. 2.3%, NS), respectively.
§ Injectable influenza vaccine made by Sanofi Pasteur, Inc.
Matched & Mismatched Efficacy in Children Aged 24 to 59 Months During 2004-2005 Influenza Season (FluMist vs. Flu Shot)1-3 II
FluMist achieved these significant reductions against matched and mismatched influenza strains:1-3
II Data is representative of the indicated population; full study population is represented in the Prescribing Information.
** The attack rates for FluMist vs. the flu shot for all matched strains circulating during the 2004-2005 flu season were as follows: A/New Caledonia (H1N1) (0.0% vs. 1.0%), A/Wyoming (H3N2) (0% vs. 0%), and matched B/Yamagata lineage (1.4% vs. 1.9%, NS), respectively.
†† The attack rates for FluMist vs the flu shot for all mismatched strains circulating during the 2004-2005 flu season were as follows: A/California-like (H3N2) (1.2% vs 4.9%), and mismatched B/Yamagata lineage and B/Victoria (2.1% vs 2.3%, NS), respectively.


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