Formoterol thrice weekly does not result in the development of tolerance to bronchoprotection
BE Davis | JK Reid | DW Cockcroft
of bronchoprotection routinely follows regular treatment
with beta2-agonists. There are no data on
the effects on bronchoprotection for thrice weekly use
of a beta2-agonist.
A double-blind, randomized, placebo controlled crossover
trial was conducted to investigate the effects of thrice
weekly administration of 12 mg of formoterol versus
placebo on bronchoprotection against methacholine. As
an expected positive control, formoterol 12 mg once
daily was also evaluated.
There was no significant difference versus placebo in
the bronchoprotective effects of 12 mg of formoterol
administered on day 8, following daily treatment for
seven days or treatment every other day (analysis of
variance P=0.34). However, a nonsignificant trend towards
lower concentration of methacholine that caused a 20%
fall in forced expiratory volume in 1 s developed only
following the daily formoterol dosing.
Thrice weekly dosing does not result in the development
of tolerance to bronchoprotection against the direct
acting stimulus methacholine.