Levosalbutamol for chronic obstructive pulmonary disease: a treatment evaluation

Introduction: Chronic obstructive pulmonary disease (COPD) is an inflammatory disorder associated with considerable morbidity and mortality. β2-adrenoceptor agonists (β2-agonists) act by stimulating the β2-adrenoceptor present on smooth muscle and other cells in the airways, resulting in bronchodilatation. β2-agonists play a central role in the treatment of breathlessness in patients with COPD. Salbutamol is a chiral drug with (R)-and (S)-isomers. Almost all β2-agonists that are currently used are racemic mixtures of (R)-and (S)-salbutamol. Areas covered: (R)-salbutamol alone (Xenopex®, generically known as levosalbutamol) is now indicated for the treatment or prevention of bronchospasm with reversible obstructive airway disease. This evaluation demonstrates that (R)-salbutamol provides a beneficial β2-agonist effect at a cellular level and in experimental models of airways disease. Furthermore, we demonstrate that (S)-salbutamol opposes the desirable effects of (R)-salbutamol and can actually cause features of asthma and COPD in vitro and in experimental asthma. Expert opinion: Despite this strong body of preclinical experimental evidence, (R)-salbutamol has not shown consistent superiority over (S)-or racemic salbutamol in the treatment of patients with COPD.