Formoterol is a beta2-agonist that has both short and long acting
bronchodilator effects. Beta2-agonists used as
bronchodilators have been synthesized as racemates that comprise (R,R) and (S,S)-enantiomers. Compounds that are beta2-selective derive their
bronchodilator effect from an interaction between the (R,R)-enantiomer and the beta2-adrenoceptor.
Arformoterol is the (R,R)-enantiomer and is distinguished from the more commonly used racemic (RR/S,S)-diasteriomer of
formoterol. Overall literature on the use of
arformoterol in
COPD is very preliminary. There is some in vitro data that demonstrate significant bronchodilation and inhibition of
inflammation with
arformoterol, and these effects may be more pronounced than those caused by racemic
formoterol. There are limited clinical trial data that demonstrate that
arformoterol produces significant improvement in lung function in
COPD; however, many of the subjects involved had marked baseline airway reversibility.
Arformoterol has been very well tolerated in clinical trials and could potentially be used only once every 24 hours (due to its prolonged effect). It can only be given in nebulized form.
Arformoterol can potentially be given with other inhaled medications.