Umeclidinium/vilanterol is a combination inhaled long-acting muscarinic receptor antagonist/long-acting beta2-adrenergic agonist (LAMA/LABA). Following oral inhalation both compounds act locally on airways to produce bronchodilation by separate mechanisms.
Umeclidinium is a long acting muscarinic receptor antagonist (also referred to as an anticholinergic). It is a quinuclidine derivative with activity across multiple muscarinic receptor subtypes. Umeclidinium exerts its bronchodilatory activity by competitively inhibiting the binding of acetylcholine with muscarinic receptors on airway smooth muscle. It demonstrates slow reversibility at the human M3 muscarinic receptor subtype in vitro and a long duration of action in vivo when administered directly to the lungs in pre-clinical models.
Vilanterol is a selective long-acting, beta2-adrenergic receptor agonist (beta2-adrenergic agonist). The pharmacologic effects of beta2-adrenergic agonists, including vilanterol, are at least in part attributable to stimulation of intracellular adenylate cyclase, the enzyme that catalyzes the conversion of adenosine triphosphate (ATP) to cyclic-3',5'-adenosine monophosphate (cyclic AMP). Increased cyclic AMP levels cause relaxation of bronchial smooth muscle and inhibition of release of mediators of immediate hypersensitivity from cells, especially from mast cells.
In Phase III, 6-month studies umeclidinium/vilanterol provided clinically meaningful improvements over placebo in lung function (as measured by forced expiratory volume in 1 second [FEV1]) over 24 hours following once daily administration, which were evident at 15 minutes following administration of the first dose (improvement over placebo by 112 ml (p<0.001*). Mean peak improvements in FEV1 within the first 6 hours following dosing relative to placebo was 224 ml (p<0.001*) at Week 24. There was no evidence for tachyphylaxis in the effect of umeclidinium/vilanterol over time.
The effect of umeclidinium/vilanterol on the QT interval was evaluated in a placebo and active (moxifloxacin) controlled QT study involving once daily administration of umeclidinium/vilanterol 113/22 micrograms or 500/100 micrograms (pre-dispensed dose with umeclidinium at eight times the recommended dose and vilanterol at four times the recommended dose) for 10 days in 103 healthy volunteers. The maximum mean difference in prolongations of QT interval (corrected using the Fridericia method, QTcF) from placebo after baseline-correction was 4.3 (90% CI=2.2 to 6.4) milliseconds seen 10 minutes after administration with umeclidinium/vilanterol 113/22 micrograms and 8.2 (90% CI=6.2 to 10.2) milliseconds seen 30 minutes after administration with umeclidinium/vilanterol 500/100 micrograms. Therefore, no clinically relevant pro-arrhythmic potential related to QT-interval prolongations was observed with umeclidinium/vilanterol 113/22 micrograms.
A dose-dependent increase in heart rate was also observed. The maximum mean difference in heart rate from placebo after baseline-correction was 8.4 (90% CI=7.0 to 9.8) beats/minute and 20.3 (90% CI=18.9 to 21.7) beats/minute seen 10 minutes after administration of umeclidinium/vilanterol 113/22 micrograms and 500/100 micrograms respectively.
In addition, no clinically significant effects on cardiac rhythm were observed on 24-hour Holter monitoring in 53 patients with COPD who were treated with umeclidinium/vilanterol 55/22 micrograms once daily in one 6-month study, or in a further 55 patients who received umeclidinium/vilanterol 113/22 micrograms once daily in another 6-month study and 226 patients who received 113/22 micrograms once daily in the 12-month study.
When umeclidinium and vilanterol were administered in combination by the inhaled route, the pharmacokinetics of each component was similar to those observed when each active substance was administered separately. For pharmacokinetic purposes each component can therefore be considered separately.
Following inhaled administration of umeclidinium in healthy volunteers, Cmax occurred at 5 to 15 minutes. The absolute bioavailability of inhaled umeclidinium was on average 13% of the dose, with negligible contribution from oral absorption. Following repeat dosing of inhaled umeclidinium, steady state was achieved within 7 to 10 days with 1.5 to 1.8-fold accumulation.
Following inhaled administration of vilanterol in healthy volunteers, Cmax occurred at 5 to 15 minutes. The absolute bioavailability of inhaled vilanterol was 27%, with negligible contribution from oral absorption. Following repeat dosing of inhaled vilanterol, steady state was achieved within 6 days with up to 2.4-fold accumulation.
Following intravenous administration to healthy volunteers, the mean volume of distribution was 86 litres. In vitro plasma protein binding in human plasma was on average 89%.
Following intravenous administration to healthy volunteers, the mean volume of distribution at steady state was 165 litres. In vitro plasma protein binding in human plasma was on average 94%.
In vitro studies showed that umeclidinium is primarily metabolised by cytochrome P450 2D6 (CYP2D6) and is a substrate for the P-glycoprotein (P-gp) transporter. The primary metabolic routes for umeclidinium are oxidative (hydroxylation, O-dealkylation) followed by conjugation (glucuronidation, etc), resulting in a range of metabolites with either reduced pharmacological activity or for which the pharmacological activity has not been established. Systemic exposure to the metabolites is low.
In vitro studies showed that vilanterol is primarily metabolised by cytochrome P450 3A4 (CYP3A4) and is a substrate for the P-gp transporter. The primary metabolic routes for vilanterol are O-dealkylation to a range of metabolites with significantly reduced beta1- and beta2-adrenergic agonist activity. Plasma metabolic profiles following oral administration of vilanterol in a human radiolabel study were consistent with high first-pass metabolism. Systemic exposure to the metabolites is low.
Plasma clearance following intravenous administration was 151 litres/hour. Following intravenous administration, approximately 58% of the administered radiolabelled dose (or 73% of the recovered radioactivity) was excreted in faeces by 192 hours post-dose. Urinary elimination accounted for 22% of the administered radiolabelled dose by 168 hours (27% of recovered radioactivity). The excretion of the drug-related material in the faeces following intravenous dosing indicated secretion into the bile. Following oral administration to healthy male volunteers, total radioactivity was excreted primarily in faeces (92% of the administered radiolabelled dose or 99% of the recovered radioactivity) by 168 hours post-dose. Less than 1% of the orally administered dose (1% of recovered radioactivity) was excreted in urine, suggesting negligible absorption following oral administration. Umeclidinium plasma elimination half-life following inhaled dosing for 10 days averaged 19 hours in healthy volunteers, with 3% to 4% excreted unchanged in urine at steady-state.
Plasma clearance of vilanterol following intravenous administration was 108 litres/hour. Following oral administration of radiolabelled vilanterol, mass balance showed 70% of the radiolabel in urine and 30% in faeces. Primary elimination of vilanterol was by metabolism followed by excretion of metabolites in urine and faeces. Vilanterol plasma elimination half-life following inhaled dosing for 10 days averaged 11 hours.
A population pharmacokinetic analysis showed that pharmacokinetics of umeclidinium and vilanterol were similar between COPD patients 65 years and older and those younger than 65 years of age.
Patients with severe renal impairment showed no evidence of an increase in systemic exposure to either umeclidinium or vilanterol (Cmax and AUC) following administration of umeclidinium/vilanterol with umeclidinium at twice the recommended dose and vilanterol at the recommended dose and no evidence of altered protein binding between patients with severe renal impairment and healthy volunteers.
Patients with moderate hepatic impairment (Child-Pugh Class B) showed no evidence of an increase in systemic exposure to either umeclidinium or vilanterol (Cmax and AUC) following administration of umeclidinium/vilanterol with umeclidinium at twice the recommended dose and vilanterol at the recommended dose and no evidence of altered protein binding between patients with moderate hepatic impairment and healthy volunteers. Umeclidinium/vilanterol has not been evaluated in patients with severe hepatic impairment.
A population pharmacokinetic analysis showed that no dose adjustment is required for umeclidinium or vilanterol based on the effect of age, race, gender, inhaled corticosteroid use, or weight. A study in CYP2D6 poor metabolisers showed no evidence of a clinically significant effect of CYP2D6 genetic polymorphism on systemic exposure to umeclidinium.
In nonclinical studies with umeclidinium and vilanterol, alone and in combination, findings were those typically associated with the primary pharmacology of either muscarinic receptor antagonists or beta2-adrenergic agonists respectively and/or local irritancy. The following statements reflect studies conducted on the individual components.
Umeclidinium was not genotoxic in a standard battery of studies and was not carcinogenic in lifetime inhalation studies in mice or rats at exposures 26 or 22-fold, times the human clinical exposure of umeclidinium 55 micrograms, based on AUC, respectively.
In genetic toxicity studies, vilanterol (as alpha-phenylcinnamate) and triphenylacetic acid were not genotoxic indicating that vilanterol (as trifenatate) does not represent a genotoxic hazard to humans. Consistent with findings for other beta2adrenergic agonists, in lifetime inhalation studies, vilanterol trifenatate caused proliferative effects in the female rat and mouse reproductive tract and in the rat pituitary gland. There was no increase in tumour incidence in rats or mice at exposures 0.5 or 13-fold, times the human clinical exposure of vilanterol 22 micrograms based on AUC, respectively.
Umeclidinium was not teratogenic in rats or rabbits. In a pre- and post-natal study, subcutaneous administration of umeclidinium to rats resulted in lower maternal body weight gain and food consumption and slightly decreased pre-weaning pup body weights in dams given 180 micrograms/kg/day dose (approximately 80-times the human clinical exposure of umeclidinium 55 micrograms, based on AUC).
Vilanterol was not teratogenic in rats. In inhalation studies in rabbits, vilanterol caused effects similar to those seen with other beta2-adrenergic agonists (cleft palate, open eyelids, sternebral fusion and limb flexure/malrotation) at 6-times the human clinical exposure based on AUC. When given subcutaneously there were no effects at 36-times the human clinical exposure of vilanterol 22 micrograms, based on AUC.
© All content on this website, including data entry, data processing, decision support tools, "RxReasoner" logo and graphics, is the intellectual property of RxReasoner and is protected by copyright laws. Unauthorized reproduction or distribution of any part of this content without explicit written permission from RxReasoner is strictly prohibited. Any third-party content used on this site is acknowledged and utilized under fair use principles.
