Mass balance and metabolism of aclidinium bromide following intravenous administration of [¹⁴C]-aclidinium bromide in healthy subjects.
ABSTRACT Aclidinium bromide is a novel, inhaled long-acting muscarinic antagonist with low systemic activity developed for the treatment of COPD. It is an ester compound rapidly hydrolysed in plasma into inactive alcohol and acid metabolites. In this Phase I, open-label study, the rates and routes of elimination of radioactivity following intravenous administration of [¹⁴C]-aclidinium bromide were determined. The metabolites of aclidinium were also characterized and identified in plasma and excreta. Twelve healthy males were randomized (1:1) to receive a single intravenous 400 µg dose of [phenyl-U-¹⁴C]- or [glycolyl-U-¹⁴C]-aclidinium bromide (via 5 min infusion) to label alcohol or acid metabolites of aclidinium, respectively. Safety and tolerability were assessed over a 9-day period. Following intravenous administration, the parent compound was rapidly hydrolysed into its acid and alcohol metabolites. Primary excretion routes for [phenyl-U-¹⁴C]- and [glycolyl-U-¹⁴C]-aclidinium were renal (urine: 65% and 54%, respectively; feces: 33% and 20%, respectively), with 1% excreted as unchanged aclidinium. A total of three treatment-emergent adverse events in two subjects were reported and were related to infusion site pain. Overall, aclidinium is rapidly hydrolysed into two main metabolites, which are predominantly excreted in urine. Aclidinium bromide 400 µg administered intravenously was safe and well tolerated in healthy subjects.
- SourceAvailable from: chestpubs.org[show abstract] [hide abstract]
ABSTRACT: The use of anticholinergic bronchodilators in COPD is based on the reversal of cholinergic bronchomotor tone. There is little information about the magnitude of cholinergic tone in patients with COPD as compared with normal subjects. As an index of the amount of cholinergic tone we measured the maximum increase in FEV1 following administration of an optimal dose of the anticholinergic agent atropine methonitrate. The study included nine normal nonsmoking subjects, ten normal smokers and 22 subjects with mild to moderately severe COPD. We found that normal nonsmokers had smallest increases in FEV1 following atropine methonitrate administration. Responses of subjects with airway disease were progressively greater. Greatest responses occurred in the group of subjects with prebronchodilator FEV1 values less than 55 percent of predicted. The most plausible explanation for this is that cholinergic tone in COPD is increased in proportion to the severity of airway disease. Other explanations are possible.Chest 12/1989; 96(5):984-7. · 5.85 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Aclidinium bromide is a novel potent, long-acting inhaled muscarinic antagonist in development for the treatment of chronic obstructive pulmonary disease. Aclidinium showed subnanomolar affinity for the five human muscarinic receptors (M(1)-M(5)). [(3)H]Aclidinium dissociated slightly faster from M(2) and M(3) receptors than [(3)H]tiotropium but much more slowly than [(3)H]ipratropium. Its association rate for the M(3) receptor was similar to [(3)H]ipratropium and 2.6 times faster than [(3)H]tiotropium. Residence half-life of [(3)H]aclidinium at the M(2) receptor was shorter than at the M(3) receptor, demonstrating kinetic selectivity for the M(3) receptor. In isolated guinea pig trachea, aclidinium showed comparable potency to ipratropium and tiotropium, faster onset of action than tiotropium, and duration of action similar to tiotropium and significantly longer than ipratropium. Nebulized aclidinium inhibited bronchoconstriction induced by acetylcholine in guinea pigs in a concentration-dependent manner with an onset of action faster than tiotropium. Duration of action of aclidinium (t(1/2) = 29 h) was much longer than ipratropium (8 h) but shorter than tiotropium (64 h). In dogs, aclidinium induced a smaller and more transient increase in heart rate than tiotropium at comparable supratherapeutic doses. Therefore, under these conditions, aclidinium showed a greater therapeutic index than tiotropium (4.2 versus 1.6). These results indicate that aclidinium is a potent muscarinic antagonist with a fast onset of action, a long duration of effect, and a favorable cardiovascular safety profile.Journal of Pharmacology and Experimental Therapeutics 09/2009; 331(2):740-51. · 3.89 Impact Factor
- [show abstract] [hide abstract]
ABSTRACT: Systemic exposure to anticholinergics used for chronic obstructive pulmonary disease (COPD) may lead to side effects. This study assessed safety, tolerability, and pharmacokinetics of multiple doses of aclidinium bromide, a novel, long-acting antimuscarinic. Sixteen healthy participants received aclidinium bromide 200, 400, or 800 microg or placebo by dry-powder inhaler for 5 days, with > or =7 days washout. Aclidinium bromide and metabolite pharmacokinetics were assessed. Aclidinium bromide plasma levels were below the lower limit of quantification (LLOQ: 0.05 ng/mL) after 200 microg and in most participants after 400 microg. Plasma levels in all participants were below the LLOQ at all doses, including the highest dose, beyond 1 hour postdose. AUC(0-t) and C(max) at steady state were, respectively, 0.08 ng.h/mL and 0.12 ng/mL (aclidinium bromide), 0.40 ng.h/mL and 0.14 ng/mL (alcohol metabolite), and 13.47 ng.h/mL and 2.26 ng/mL (acid metabolite). The t(max) for aclidinium bromide 800 microg was 15 minutes (first kinetic time point). Adverse event frequency was comparable between treatment groups and placebo. The most commonly reported adverse events, probably treatment related, were coughing (n = 2) and dysphagia (n = 1); 94% of adverse events were mild. These data suggest a low systemic bioavailability and favorable safety profile for aclidinium bromide with repeated dosing for COPD.The Journal of Clinical Pharmacology 07/2009; 49(10):1239-46. · 2.84 Impact Factor