Safety, tolerability and pharmacokinetics of single escalating doses of indacaterol, a once-daily beta2-agonist bronchodilator, in subjects with COPD.

OBJECTIVES: To assess the safety and tolerability of 4 doses of indacaterol, a once-daily beta2-agonist, in subjects with chronic obstructive pulmonary disease (COPD). The 24-h bronchodilator effect and pharmacokinetics of indacaterol were also investigated. METHODS: 16 subjects aged 43 - 72 years with mild/moderate COPD were each given single doses of indacaterol of 400, 1,000, 2,000 and 3,000 µg, via a single-dose dry powder inhaler. RESULTS: Changes from predose (400, 1,000, 2,000, 3,000 µg doses, respectively) were as follows. Maximum mean decreases in fasting (up to 2 h post-dose) serum potassium were 0.12, 0.30, 0.38, 0.26 mmol/l; maximum mean increases (up to 2 h post-dose) in fasting serum glucose were 0.12, 0.40, 0.87, 1.01 mmol/l. The maximum increase in heart rate (by 3, 6, 12, 13 beats/min, respectively) was within 1 h post-dose. No clinically significant electrocardiogram abnormalities were reported. Most adverse events were mild or moderate, with none considered serious or leading to withdrawal. Indacaterol was rapidly absorbed and displayed multiphasic disposition kinetics. The terminal elimination phase with a half-life of 50 - 63 h could only be seen for doses of 1,000 µg or higher. Mean systemic exposure to indacaterol (AUC0-24) increased by ~ 9-fold from 400 to 3,000 µg. CONCLUSION: Even at doses far in excess of the therapeutic range, indacaterol had minimal systemic effects; such changes would be considered within safe limits for a single dose.

Bronchodilator effects of indacaterol and formoterol in patients with COPD.

BACKGROUND: Resting inspiratory capacity (IC) reflects static hyperinflation in chronic obstructive pulmonary disease (COPD). This study compared the effects of formoterol and indacaterol, a novel once-daily ultra-long-acting beta(2)-agonist (or ultra-LABA), on resting IC and forced expiratory volume in 1 s (FEV(1)). METHODS: Thirty patients with COPD (mean FEV(1)/FVC 0.49, mean FEV(1) 56% predicted) each inhaled three treatments (two in randomized sequence followed by open-label formoterol) on separate study days: a single dose of indacaterol 300 microg, matching placebo, and two doses of formoterol 12 microg 12 h apart. RESULTS: Indacaterol and formoterol increased FEV(1) and IC at all time points relative to placebo (p<0.001). Peak effects on FEV(1) were similar, while indacaterol had a greater effect on peak IC (31% vs 23% from pre-dose; p=0.034). Indacaterol had a greater effect than formoterol on FEV(1) at 8 h (1.47 vs 1.39 L; p=0.014) and 24 h (1.44 vs 1.35 L; p=0.003), and on IC from 4 to 24 h (differences of 0.13-0.19 L; p<0.05). At 24 h, indacaterol and formoterol increased FEV(1) by 17.7% and 7.5%, respectively, from pre-dose. CONCLUSIONS: This study discriminated between the effects on IC and FEV(1) of once daily indacaterol and twice daily formoterol. The greater effect of indacaterol on IC may translate into improved long-term clinical outcomes.

Pharmacokinetics of valsartan in patients with liver disease.

OBJECTIVES: Valsartan (CGP 48933), an orally active angiotensin II antagonist, is eliminated mainly by hepatic clearance. To characterize the compound(s) excreted in the bile, biliary excretion of valsartan was investigated by collection of bile after an intravenous dose of valsartan. In addition, to determine the exposure to valsartan when liver function is impaired, a pharmacokinetic study (open, single dose) was performed in patients with mild and moderate impairment of liver function. PATIENTS: Biliary excretion of valsartan (after intravenous administration of 20 mg valsartan) was assessed in a patient who underwent a hepaticojejunostomy with subsequent bile drainage. Exposure to valsartan in patients with mild (n = 6) or moderate (n = 6) impaired liver function (Child's-Pugh classification) and matching (sex, age, and weight) healthy volunteers (n = 12) was studied after oral administration of a single dose of 160 mg valsartan. RESULTS: After intravenous administration, valsartan was eliminated mainly as unchanged drug in the bile. Mean exposure (measured as area under the plasma valsartan concentration-time curve) to valsartan was increased about twofold in both the mild and the moderate groups compared with matched (age, sex, and weight) healthy volunteers. CONCLUSION: These data are consistent with the pharmacokinetics of valsartan in that biliary excretion is the main route of elimination.

Effect of renal impairment on the pharmacokinetics and pharmacodynamics of desirudin.

OBJECTIVE: To investigate the pharmacokinetics and pharmacodynamics of desirudin in subjects with various degrees of renal impairment in comparison with subjects with normal renal function. METHODS: Eight subjects with normal renal function (creatinine clearance > 90 ml/min) received 0.5 mg/kg desirudin intravenously over 30 minutes. Four subjects with mild renal failure (creatinine clearance between 61 and 90 ml/min) received 0.5 mg/kg. Five subjects with moderate renal failure (creatinine clearance between 31 and 60 ml/min) received 0.25 mg/kg. Six subjects with severe renal failure (creatinine clearance < 31 ml/min) received 0.125 mg/kg. RESULTS: Specific maximum concentration values (maximum concentrations corrected to a dose of 1 mg/kg) increased slightly with decreasing creatinine clearance. Mean specific area under the plasma concentration-time curve increased by a factor of 1.15, 2.83, and 7.0 for subjects with mild, moderate, and severe renal failure, respectively, compared with healthy subjects. Total urinary excretion of desirudin was about 55% to 60% of the dose in all four groups; elimination was delayed for subjects with moderate and severe renal failure. Total and renal clearance of desirudin were proportional to creatinine clearance. Total plasma clearance of desirudin was proportional to renal clearance of the drug. Prolongation of activated partial thromboplastin time was increased among subjects with moderate and severe renal failure despite a dose reduction. Area under the dynamic activated partial thromboplastin time curve for subjects with moderate renal failure remained the same as that for healthy subjects despite a dose reduction by a factor of two. Area under the dynamic curve increased by a factor of about 1.5 for subjects with severe renal failure despite a dose reduction by a factor of four. CONCLUSION: A dose reduction by a factor of six is recommended for persons with severe renal failure.

R-[N-acetyl]eglin c:poly(oxyethylene) conjugates: preparation, plasma persistence, and urinary excretion.

In this paper, we describe the preparation, purification, and characterization of conjugates of R-[N-acetyl]eglin c (Eglin c) with poly(oxyethylene) (POE; Eglin c:POE). The plasma profile and urinary excretion of the conjugates has been determined after iv administration in mice. The modification of Eglin c with POE does not significantly impair the ability of Eglin c to bind elastase as measured by an in vitro assay. In the best example, 79% of theoretical activity was retained by the conjugate. The in vivo results clearly show that the amount of Eglin c:POE in plasma after iv administration is much higher than comparative doses of unconjugated Eglin c. The time course of the plasma concentration of the conjugate matches closely that of the corresponding free polymer. Consequently, we can expect that higher plasma concentration could be achieved, if and when required, by selecting polymers of appropriate size.