The trial was a prospective, multi-center, double-blind, placebo-controlled,
randomized control trial.1
healthy children, ages 15-71 months old (average age 43 m/o), were randomized
in a 2:1 ratio to receive the live, intranasal influenza vaccine versus
placebo. Exclusion criteria included egg allergy and respiratory, cardiovascular,
and immuno-deficiency related chronic illnesses.
placebo was clinically indistinguishable from the experimental vaccine,
containing the same inactive ingredients as the vaccine.
vaccination, both groups were actively monitored for clinical symptoms
suggestive of influenza infection (e.g., fever, malaise, headaches,
congestion, myalgias, etc.). If subjects demonstrated the aforementioned
symptoms, an influenza culture was sent to determine influenza infection
to the vaccine's viral strains versus other viral etiology as the cause.
were further monitored for the vaccine's tolerability, and antibody
response via scheduled blood draws.
the 1070 subjects randomized to the vaccination arm, 14 had culture
confirmed influenza (1%). Among the 532 control subjects, 95 experienced
one or more influenza infections (>17%).
vaccine's overall efficacy, also referred to a Relative Risk Reduction
(RRR), was determined to be 93% (95% Confidence Interval=88-96%).
the vaccine's Absolute Risk Reduction (ARR) was 17%, and its Number
Needed to Treat (NNT) was 6 patients.