Blocking FcRn in humans reduces circulating IgG levels and inhibits IgG immune complex-mediated immune responses.

The neonatal crystallizable fragment receptor (FcRn) functions as an intracellular protection receptor for immunoglobulin G (IgG). Recently, several clinical studies have reported the lowering of circulating monomeric IgG levels through FcRn blockade for the potential treatment of autoimmune diseases. Many autoimmune diseases, however, are derived from the effects of IgG immune complexes (ICs). We generated, characterized, and assessed the effects of SYNT001, a FcRn-blocking monoclonal antibody, in mice, nonhuman primates (NHPs), and humans. SYNT001 decreased all IgG subtypes and IgG ICs in the circulation of humans, as we show in a first-in-human phase 1, single ascending dose study. In addition, IgG IC induction of inflammatory pathways was dependent on FcRn and inhibited by SYNT001. These studies expand the role of FcRn in humans by showing that it controls not only IgG protection from catabolism but also inflammatory pathways associated with IgG ICs involved in a variety of autoimmune diseases.

Pharmacokinetics, Safety, and CCR2/CCR5 Antagonist Activity of Cenicriviroc in Participants With Mild or Moderate Hepatic Impairment.

Cenicriviroc, a dual CCR2/CCR5 antagonist, is being evaluated for treatment of nonalcoholic steatohepatitis and liver fibrosis (CENTAUR; NCT02217475). As it is metabolized by the liver, cenicriviroc was investigated in hepatic-impaired participants for pharmacokinetic changes. Participants with mild-to-moderate hepatic impairment (HI) (Child-Pugh class A (N  =  7) or B (N = 8)) and matched controls (N = 15) received cenicriviroc 150 mg once daily for 14 days. Serial blood samples were obtained on Days 1 and 14. Safety, tolerability, and effects on CCR2/CCR5 ligands, cytokines, and bacterial translocation biomarkers were evaluated. Cenicriviroc exposures were increased by moderate HI (AUC0-τ  55%, Cmax 29% higher) but were not with mild HI (AUC0-τ 38%, Cmax 40% lower). Cenicriviroc was well tolerated. Rapid and potent CCR2/CCR5 blockade was observed, not associated with increases in hepatic inflammation or bacterial translocation biomarkers. Study findings suggest that cenicriviroc 150 mg can be used in patients with mild-to-moderate HI.

Safety and pharmacokinetics of multiple doses of aclidinium bromide administered twice daily in healthy volunteers.

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airway obstruction and increased cholinergic tone. The global initiative for chronic obstructive lung disease (GOLD) guidelines recommend long-acting anticholinergics for COPD maintenance treatment. Aclidinium bromide is a novel, long-acting muscarinic antagonist developed for the treatment of COPD. A phase I, randomized, single-blind, multiple-dose clinical trial was conducted to assess the safety and pharmacokinetics (PK) of multiple doses of twice-daily (BID) aclidinium in healthy subjects. Thirty healthy male and female subjects received aclidinium 200 µg, 400 µg, 800 µg, or placebo twice daily for 7 days. Subjects were randomized to 1 of 3 cohorts and 10 subjects in each cohort were randomized (8:2) to either aclidinium or placebo groups. Safety was assessed via adverse events (AEs), laboratory evaluations, vital signs, and ECGs. Plasma samples were obtained at multiple time points throughout the study and analyzed for aclidinium and its inactive acid and alcohol metabolites using a fully validated method of liquid chromatography coupled with tandem mass spectrometry. A total of 9 treatment-emergent AEs were reported (1, placebo; 3, aclidinium 400 µg; 5, aclidinium 800 µg), all of which were mild in severity. No serious AEs were reported. There were no clinically meaningful changes in laboratory parameters or vital signs. PK parameters on Day 7 following BID dosing of aclidinium showed that steady state was achieved for aclidinium and its metabolites. On Days 1 and 7, maximum plasma concentrations (Cmax) of aclidinium were generally observed at the first PK time point (5 min postdose) and rapidly declined, with plasma concentrations generally less than 10% of Cmax by 6 h postdose in all aclidinium groups. Mean effective t(½) after the evening dose on Day 7 ranged from 4.6 to 7.0 h for aclidinium 400 µg and 800 µg, similar to the terminal t(½) observed on Day 1 (4.5-5.9 h). Exposure for aclidinium and both metabolites increased with increasing dose, with the increase in exposure being less than dose proportional between the 400 µg and 800 µg doses. Overall, all doses of aclidinium were safe and well tolerated throughout the study. Pharmacokinetic steady state was reached for aclidinium and both metabolites within the 7-day treatment period for all doses tested. Aclidinium bromide exhibited time-independent PK following dosing to steady state, indicating that similar concentration versus time profiles will occur after repeated administration at the same dose and frequency.

Safety, tolerability, and pharmacokinetics of raltegravir after single and multiple doses in healthy subjects.

Raltegravir is a novel human immunodeficiency virus-1 integrase inhibitor with potent in vitro activity (95% inhibitory concentration (IC95)=33 nM in 50% human serum). Three double-blind, randomized, placebo-controlled, pharmacokinetic, safety, and tolerability studies were conducted: (1) single-dose escalation study (10-1,600 mg), (2) multiple-dose escalation study (100-800 mg q12 h x 10 days), and (3) single-dose female study (400 mg). Raltegravir was rapidly absorbed with a terminal half-life (t1/2) approximately 7-12 h. Approximately 7-14% of raltegravir was excreted unchanged in urine. Area under the curve (AUC)(0-infinity) was similar between male and female subjects. After multiple-dose administration, steady state was achieved within 2 days; there was little to modest accumulation of raltegravir. Trough levels were >33 nM for dose levels of 100 mg and greater. Raltegravir is generally well tolerated at doses of up to 1,600 mg/day given for up to 10 days and exhibits a pharmacokinetic profile supportive of twice-daily dosing with multiple doses of 100 mg and greater achieving trough levels >33 nM.

The influence of hepatic impairment on the pharmacokinetics of the dipeptidyl peptidase IV (DPP-4) inhibitor vildagliptin.

OBJECTIVE: Vildagliptin is a potent and selective dipeptidyl peptidase-IV (DPP-4) inhibitor that improves glycemic control in patients with type 2 diabetes mellitus by increasing alpha- and beta-cell responsiveness to glucose. This study investigated the pharmacokinetics of vildagliptin in patients with hepatic impairment compared with healthy subjects. METHODS: This was an open-label, parallel-group study in patients with mild (n = 6), moderate (n = 6) or severe (n = 4) hepatic impairment and healthy subjects (n = 6). All subjects received a single 100-mg oral dose of vildagliptin, and plasma concentrations of vildagliptin and its main pharmacologically inactive metabolite LAY151 were measured up to 36 h post-dose. RESULTS: Exposure to vildagliptin (AUC(0-infinity) and C(max)) decreased non-significantly by 20 and 30%, respectively, in patients with mild hepatic impairment [geometric mean ratio (90% CI): AUC(0-infinity), 0.80 (0.60, 1.06), p = 0.192; C(max), 0.70 (0.46, 1.05), p = 0.149]. Exposure to vildagliptin was also decreased non-significantly in patients with moderate hepatic impairment [-8% for AUC(0-infinity), geometric mean ratio (90% CI): 0.92 (0.69, 1.23), p = 0.630; -23% for C(max), geometric mean ratio (90% CI): 0.77 (0.51, 1.17), p = 0.293]. In patients with severe hepatic impairment, C(max) was 6% lower than that in healthy subjects [geometric mean ratio (90% CI): 0.94 (0.59, 1.49), p = 0.285], whereas AUC(0-infinity) was increased by 22% [geometric mean ratio (90% CI): 1.22 (0.89, 1.68), p = 0.816). Across the hepatic impairment groups, LAY151 AUC(0-infinity) and C(max) were increased by 29-84% and 24-63%, respectively, compared with healthy subjects. The single 100-mg oral dose of vildagliptin was well tolerated by patients with hepatic impairment. CONCLUSIONS: There was no significant difference in exposure to vildagliptin in patients with mild, moderate or severe hepatic impairment; therefore, no dose adjustment of vildagliptin is necessary in patients with hepatic impairment.

Predictive power of an in vitro system to assess drug interactions of an antimuscarinic medication: a comparison of in vitro and in vivo drug-drug interaction studies of trospium chloride with digoxin.

The authors studied a potential drug-drug interaction via findings from in vitro and in vivo studies, to assess whether the in vitro system was predictive of in vivo clinical pharmacokinetic outcomes. An in vitro experiment and a clinical study were performed to assess the potential for interaction. The effect of trospium chloride on human P-glycoprotein-mediated transport of [3H]-digoxin was determined in vitro. A randomized, crossover clinical trial in 40 subjects was performed to evaluate the effect of trospium on the pharmacokinetics of digoxin in vivo. The findings from the studies were then compared. The in vitro findings in this study were corroborated by the clinical study via assessment of inhibition and impact on pharmacokinetic parameters. The in vitro system for assessment of a potential interaction of 2 drugs excreted primarily through the kidney was predictive of the pharmacokinetic outcomes obtained from a clinical setting.

Bioequivalence of an ezetimibe/simvastatin combination tablet and coadministration of ezetimibe and simvastatin as separate tablets in healthy subjects.

OBJECTIVE: To assess the bioequivalence of an ezetimibe/simvastatin (EZE/SIMVA) combination tablet compared to the coadministration of ezetimibe and simvastatin as separate tablets (EZE + SIMVA). METHODS: In this open-label, randomized, 2-part, 2-period crossover study, 96 healthy subjects were randomly assigned to participate in each part of the study (Part I or II), with each part consisting of 2 single-dose treatment periods separated by a 14-day washout. Part I consisted of Treatments A (EZE 10 mg + SIMVA 10 mg) and B (EZE/SIMVA 10/10 mg/mg) and Part II consisted of Treatments C (EZE 10 mg + SIMVA 80 mg) and D (EZE/SIMVA 10/80 mg/mg). Blood samples were collected up to 96 hours post-dose for determination of ezetimibe, total ezetimibe (ezetimibe + ezetimibe glucuronide), simvastatin and simvastatin acid (the most prevalent active metabolite of simvastatin) concentrations. Ezetimibe and simvastatin acid AUC(0-last) were predefined as primary endpoints and ezetimibe and simvastatin acid Cmax were secondary endpoints. Bioequivalence was achieved if 90% confidence intervals (CI) for the geometric mean ratios (GMR) (single tablet/coadministration) of AUC(0-last) and Cmax fell within prespecified bounds of (0.80, 1.25). RESULTS: The GMRs of the AUC(0-last) and Cmax for ezetimibe and simvastatin acid fell within the bioequivalence limits (0.80, 1.25). EZE/ SIMVA and EZE + SIMVA were generally well tolerated. CONCLUSIONS: The lowest and highest dosage strengths of EZE/SIMVA tablet were bioequivalent to the individual drug components administered together. Given the exact weight multiples of the EZE/SIMVA tablet and linear pharmacokinetics of simvastatin across the marketed dose range, bioequivalence of the intermediate tablet strengths (EZE/SIMVA 10/20 mg/mg and EZE/SIMVA 10/40 mg/mg) was inferred, although these dosages were not tested directly. These results indicate that the safety and efficacy profile of EZE + SIMVA coadministration therapy can be applied to treatment with the EZE/SIMVA tablet across the clinical dose range.

FTY720 pharmacokinetics in mild to moderate hepatic impairment.

The influence of mild and moderate hepatic impairment on FTY720 pharmacokinetics was assessed. The authors enrolled 32 subjects consisting of 8 with mild and 8 with moderate hepatic impairment based on Child-Pugh criteria and 16 demographically matched control subjects. A single 1-mg oral dose of FTY720 was administered under fasting conditions. Blood, plasma, and urine samples were obtained over a 14-day period for measurement of FTY720 and metabolite concentrations and protein binding. Total blood lymphocyte counts and heart rate were serially monitored to assess pharmacologic responses to FTY720. Peak FTY720 blood concentrations were similar across groups. Oral clearance (CL/F) was reduced 10% in mild hepatic impairment (P = .493) and 31% in moderate hepatic impairment (P = .034). There were no significant differences in blood exposure to the hexanoic or butanoic acid metabolites among groups. The effect of FTY720 on blood lymphocytes was similar across groups, with a mean decrease of 44% from the predose value. Like-wise, the effect of FTY720 on supine heart rate was similar across groups, with a mean 13% decrease from the predose rate occurring 2 to 4 hours postdose and recovering within 1 to 2 days. Although hepatic impairment elicited changes in the disposition of FTY720, the magnitude of these changes suggests that the FTY720 dose does not need to be adjusted in mild or moderate hepatic-impaired patients.

No influence of moderate hepatic impairment on the pharmacokinetics of lumiracoxib, an oral COX-2 selective inhibitor.

The aim of this study was to evaluate the influence of hepatic impairment on the pharmacokinetics (PK) of the novel cyclooxygenase-2 (COX-2) selective inhibitor lumiracoxib (Prexige), so that dose recommendations for clinical use can be provided. This was an open-label, single dose, case-controlled study in which eight subjects with liver cirrhosis classed as moderate hepatic impairment (Child-Pugh score: 7-9) and eight demographically-matched healthy subjects received a single oral 400 mg dose of lumiracoxib. Routine safety assessments were made and blood samples were taken for determination of lumiracoxib concentrations for 96 h post dose. The ex vivo binding of lumiracoxib to plasma proteins was determined pre dose and at 2 and 12 h post dose. An analysis of variance was used to detect differences in PK parameters (AUC, Cmax and Tmax) between the treatment groups. There were no significant differences between subjects with moderate hepatic insufficiency and healthy subjects in the area under the lumiracoxib plasma concentration-time curves (AUC(0-infinity)): 29.2 +/- 6.7 microg h ml(-1) versus 28.7 +/- 6.3 mircrog h ml(-1). The rate of absorption of lumiracoxib was not significantly altered by hepatic impairment based on Cmax and Tmax. The protein-bound fraction of lumiracoxib exceeded 98% both in healthy control subjects and in those with moderate hepatic insufficiency. A single dose of 400 mg lumiracoxib was well tolerated. In conclusion, no dose adjustments appear to be required when lumiracoxib is administered to patients with either mild or moderate hepatic impairment.

Pharmacokinetics and pharmacodynamics of rosuvastatin in subjects with hepatic impairment.

OBJECTIVE: To assess the effect of chronic hepatic impairment on rosuvastatin disposition, pharmacodynamic activity and tolerability. METHODS: This was an open-label, non-randomised, parallel-group trial. Six subjects were enrolled in each of three hepatic-function strata: Child-Pugh class A (CP-A, mild impairment), Child-Pugh class B (CP-B, moderate impairment) and normal hepatic function; the latter two strata were age, weight, race, sex and smoking history matched. All subjects were given rosuvastatin 10 mg for 14 days. RESULTS: In subjects with CP-A, and in four of six subjects with CP-B, rosuvastatin steady-state AUC(0-24) and C(max) were similar to subjects with normal hepatic function (geometric mean values 60.7 ng h/ml and 6.02 ng/ml, respectively). Two of six subjects with CP-B who had the highest CP scores (i.e. the highest degrees of hepatic impairment) had the highest AUC(0-24) (128 ng h/ml and 242 ng h/ml) and C(max) (23.4 ng/ml and 96.7 ng/ml) values. Low-density lipoprotein cholesterol (LDL-C) was decreased in all strata, but the response was more variable in the CP-B group. Rosuvastatin was well tolerated, and the safety profile was similar in subjects with hepatic impairment and normal hepatic function. CONCLUSION: In most subjects with mild-to-moderate hepatic impairment, the steady-state pharmacokinetics of rosuvastatin were similar to subjects with normal hepatic function (more extensive hepatic impairment may increase systemic exposure to rosuvastatin), and most had LDL-C reductions similar to subjects with normal hepatic function.

Comparison of rofecoxib, celecoxib, and naproxen on renal function in elderly subjects receiving a normal-salt diet.

BACKGROUND: This study compared directly the renal effects of two selective cyclooxygenase (COX)-2 inhibitors (rofecoxib and celecoxib) with naproxen (dual COX-1/COX-2 inhibitor) and placebo in healthy elderly subjects on a sodium-replete diet. METHODS: A total of 67 elderly subjects stabilized in the clinic for weight and urinary sodium on a controlled 200-mEq sodium diet were randomized in a double-blind fashion to receive rofecoxib, 25 mg daily (n = 17); celecoxib, 200 mg twice daily (n = 17); naproxen, 500 mg twice daily (n = 17); or matching placebo (n = 16) for 28 days. Subjects were sequestered in the clinic for the first 14 treatment days on the controlled diet. RESULTS: Daily urinary sodium excretion during the first 72 hours of treatment (primary endpoint) significantly decreased in rofecoxib, celecoxib, and naproxen groups compared with baseline (P < or =.05). Rofecoxib and celecoxib decreases in urinary sodium excretion rates that were comparable with each other, on the basis of predefined boundaries (-39.5 versus -27.1 mEq/d, respectively) and to naproxen (-40.6, mEq/d). Rofecoxib, celecoxib, and naproxen increased mean systolic blood pressure to a similar degree (3.4, 4.3, and 3.1 mm Hg, respectively, versus -1.3 mm Hg for placebo) after 14 days of treatment; small changes also occurred in diastolic blood pressure (0.3, 0.8, and -0.4 mm Hg, respectively, versus -1.4 mm Hg for placebo). Changes from baseline in creatinine clearance, body weight, and urinary potassium excretion among active treatments were similar. After 28 days of treatment, findings were generally consistent with those at 14 days. No subject reported edema or discontinued treatment as the result of an adverse experience. CONCLUSION: In healthy elderly subjects on a sodium-replete diet, the COX-2 inhibitors rofecoxib and celecoxib did not differ from a nonselective nonsteroidal anti-inflammatory drug (naproxen), in influencing renal function as measured by urinary sodium excretion, systolic and diastolic blood pressure, creatinine clearance, or weight change.

Omapatrilat versus lisinopril: efficacy and neurohormonal profile in salt-sensitive hypertensive patients.

Omapatrilat, a vasopeptidase inhibitor, simultaneously inhibits neutral endopeptidase and ACE. The efficacy and hormonal profile of omapatrilat and lisinopril were compared in salt-sensitive hypertensive patients. On enrollment, antihypertensive medications were withdrawn, and patients received a single-blind placebo. On day 15, salt-sensitivity determinations were made. Salt-sensitive hypertensive patients returned within 5 to 10 days for baseline evaluations of ambulatory diastolic blood pressure, ambulatory systolic blood pressure, and atrial natriuretic peptide. Salt-sensitive hypertensive patients were randomized to receive double-blind omapatrilat (n=28) or lisinopril (n=33) at initial doses of 10 mg for 1 week, increasing to 40 and 20 mg, respectively, for an additional 3 weeks. Ambulatory blood pressure and urinary atrial natriuretic peptide were assessed at study termination. Both omapatrilat and lisinopril significantly reduced mean 24-hour ambulatory diastolic and systolic blood pressures; however, omapatrilat produced significantly greater reductions in mean 24-hour ambulatory diastolic blood pressure (P=0.008), ambulatory systolic blood pressure (P=0.004), and ambulatory mean arterial pressure (P=0.005) compared with values from lisinopril. Both drugs potently inhibited ACE over 24 hours. Omapatrilat significantly (P<0.001) increased urinary excretion of atrial natriuretic peptide over 0- to 24-hour (3.8-fold) and 12- to 24-hour (2-fold) intervals; lisinopril produced no change. Omapatrilat significantly (P<0.001) increased urinary excretion of cGMP over the 0- to 24- and 4- to 8-hour intervals compared with that from lisinopril. Neither drug had a diuretic, natriuretic, or kaliuretic effect. In conclusion, in salt-sensitive hypertensive patients, omapatrilat demonstrated the hormonal profile of a vasopeptidase inhibitor and lowered ambulatory diastolic and systolic blood pressures more than lisinopril.

Influence of hepatic impairment on everolimus pharmacokinetics: implications for dose adjustment.

OBJECTIVE: We assessed the influence of hepatic impairment on the pharmacokinetics of the immunosuppressant everolimus to provide dose recommendations for clinical use. METHODS: In this open-label, single-dose, case-control study, 8 subjects with liver cirrhosis classed as moderate hepatic impairment (Child-Pugh score, 7-9) and 8 demographically matched healthy control subjects received a single oral 2-mg dose of everolimus. Routine safety assessments were made, and blood samples were taken for determination of everolimus concentrations and protein binding. RESULTS: The apparent clearance of everolimus was significantly reduced by 53% in subjects with moderate hepatic impairment compared with healthy subjects (9.1 +/- 3.1 versus 19.4 +/- 5.8 L/h). This was manifested by a 115% higher area under the blood concentration-time curve (AUC) (245 +/- 91 versus 114 +/- 45 ng. h/ml) and 84% prolonged half-life (79 +/- 42 versus 43 +/- 18 hours) in subjects with hepatic impairment. The rate of absorption of everolimus was not altered by hepatic impairment on the basis of the maximum blood concentration (C(max)) and time to reach C(max) (t(max)). Protein binding was similar in the two groups (73.8% +/- 3.6% versus 73.5% +/- 2.4%). A significant positive correlation of the everolimus AUC with bilirubin level (r = 0.86) and a significant negative correlation with albumin concentration (r = 0.72) was observed. CONCLUSIONS: The dose of everolimus should initially be reduced by half in patients with mild and moderate hepatic impairment on the basis of the Child-Pugh classification. Therapeutic monitoring would be a helpful adjunct to subsequent titration of everolimus exposure in this subpopulation. Everolimus has not been assessed in patients with severe hepatic impairment.

Tegaserod coadministration does not alter the pharmacokinetics of theophylline in healthy subjects.

Tegaserod (HTF 919), a selective 5-HT4 receptor partial agonist, is in development for the treatment of functional gastrointestinal motility disorders. Tegaserod has been found to inhibit cytochrome P-450 (CYP) 1A2, for which theophylline is a prototype substrate. This study was designed to assess the effect of tegaserod on the single-dose pharmacokinetic and safety profile of theophylline. Eighteen subjects were enrolled in a randomized, open-label, two-period crossover study. After an overnight fast, subjects were randomized to receive one of two treatments: (1) a single dose of controlled-release formulation of theophylline (Theo-Dur, 600 mg) on day 1 or (2) a single dose of tegaserod (6 mg) on day 1, concomitant administration of tegaserod (6 mg) and theophylline (600 mg) on the morning of day 2, followed by an additional dose of tegaserod (6 mg) 12 hours later. Four to 10 days later, the subjects received the alternative treatment regimen. The pharmacokinetic parameters of theophylline, including AUC, Cmax, and t(1/2lambda z), were similar for both treatment regimens, although the tmax of theophylline was statistically different between the treatments. Except for a decrease in partial metabolic formation clearance from theophylline to 1-methyluric acid, which is unlikely to be clinically relevant, there were no statistically significant differences in renal clearance of theophylline and partial metabolic formation clearances following the combined treatment compared with theophylline alone. The results of the current study indicate that no dose adjustment is required when drugs metabolized via CYP1A2 are coadministered with tegaserod.

Interactions between simvastatin and troglitazone or pioglitazone in healthy subjects.

Two randomized, two-period crossover studies were conducted to evaluate the effects of repeat oral dosing of troglitazone (Study I) and pioglitazone (Study II) on the pharmacokinetics of plasma HMG-CoA reductase inhibitors following multiple oral doses of simvastatin and of simvastatin on the plasma pharmacokinetics of troglitazone (Study I) in healthy subjects. In both studies, each subject received two treatments. Treatment A consisted of once-daily oral doses of troglitazone 400 mg (Study I) or pioglitazone 45 mg (Study II) for 24 days with coadministration of once-daily doses of simvastatin 40 mg (Study I) or 80 mg (Study II) on Days 15 through 24. Treatment B consisted of once-daily oral doses of simvastatin 40 mg (Study I) or 80 mg (Study II) for 10 days. In Study I, the area under the plasma concentration-time profiles (AUC) and maximum plasma concentrations (Cmax) of HMG-CoA reductase inhibitors in subjects who received both troglitazone and simvastatin were decreased modestly (by approximately 30% for Cmax and approximately 40% for AUC), but time to reach Cmax (tmax) did not change, as compared with those who received simvastatin alone. Simvastatin, administered orally as a 40 mg tablet daily for 10 days, did not affect the AUC or tmax (p > 0.5) but caused a small but clinically insignificant increase (approximately 25%) in Cmax for troglitazone. In Study II, pioglitazone, at the highest approved dose for clinical use, did not significantly alter any of the pharmacokinetic parameters (AUC, Cmax, and tmax) of simvastatin HMG-CoA reductase inhibitory activity. For all treatment regimens, side effects were mild and transient, suggesting that coadministration of simvastatin with either troglitazone or pioglitazone was well tolerated. The modest effect of troglitazone on simvastatin pharmacokinetics is in agreement with the suggestion that troglitazone is an inducer of CYP3A. The insignificant effect of simvastatin on troglitazone pharmacokinetics is consistent with the conclusion that simvastatin is not a significant inhibitor for drug-metabolizing enzymes. The lack of pharmacokinetic effect of pioglitazone on simvastatin supports the expectation that this combination may be used safely.

Multiple-dose pharmacokinetics of a contraceptive patch in healthy women participants.

This open-label, randomized study evaluated the pharmacokinetics of norelgestromin (NGMN) and ethinyl estradiol (EE) following the application of a contraceptive patch (1/week) for three cycles (3 weeks/cycle). Healthy women (n = 24) wore a 20-cm(2) patch (ORTHO EVRA/EVRA) on either their abdomen or buttock during blood sampling weeks and on any of four approved sites at other times. Serum was analyzed for NGMN and EE from samples taken during Week 1 of Cycle 1 and Weeks 1-3 of Cycle 3. Steady-state conditions were achieved during the three-cycle study. The patch delivered NGMN and EE at steady-state concentrations within their reference ranges throughout three cycles of treatment; reference ranges are based on studies with ORTHO-CYCLEN/Cilest. Steady-state serum concentrations and area under the curve from 0 to 168 h increased only slightly from Cycle 1, Week 1 to Cycle 3, Week 3 for NGMN and EE, indicating minimal accumulation. Treatment was well tolerated, and patch adhesion was excellent.

Itraconazole alters the pharmacokinetics of atorvastatin to a greater extent than either cerivastatin or pravastatin.

BACKGROUND: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are metabolized by distinct pathways that may alter the extent of drug-drug interactions. Cerivastatin is metabolized by cytochrome P450 (CYP)3A4 and CYP2C8. Atorvastatin is metabolized solely by CYP3A4, and pravastatin metabolism is not well defined. Coadministration of higher doses of these statins with CYP3A4 inhibitors has the potential for eliciting adverse drug-drug interactions. OBJECTIVE: To determine the comparative effect of itraconazole, a potent CYP3A4 inhibitor, on the pharmacokinetics of cerivastatin, atorvastatin, and pravastatin. METHODS: In this single-site, randomized, three-way crossover, open-labeled study, healthy subjects (n = 18) received single doses of cerivastatin 0.8 mg, atorvastatin 20 mg, or pravastatin 40 mg without and with itraconazole 200 mg. Pharmacokinetic parameters [AUC(0-infinity), AUC(0-tn), peak concentration (Cmax), time to reach Cmax (tmax), and half-life (t1/2)] were determined for parent statins and major metabolites. RESULTS: Concomitant cerivastatin/itraconazole treatment produced small elevations in the cerivastatin AUC(0-infinity), Cmax, and t1/2 (27%, 25%, and 19%, respectively; P < .05 versus cerivastatin alone). Itraconazole coadministration produced similar changes in pravastatin pharmacokinetics [AUC elevated 51% (P < .05 versus pravastatin alone), 24% (Cmax), and 23% (t1/2), respectively]. However, itraconazole dramatically increased atorvastatin AUC (150%), Cmax (38%), and t1/2 (30%) (P < .05). The elevation in atorvastatin AUC was significantly greater than that of cerivastatin (P < .005) or pravastatin (P < .005). CONCLUSION: Itraconazole markedly elevated atorvastatin plasma levels (2.5-fold) after 20 mg dosing, suggesting that concomitant itraconazole/atorvastatin therapy be carefully considered. Itraconazole produced modest elevations in the plasma levels of cerivastatin 0.8 mg or pravastatin 40 mg (1.3-fold and 1.5-fold, respectively), indicating that combination treatment with itraconazole with cerivastatin or pravastatin may be preferable.

Effect of cyclooxygenase-2 inhibition on renal function in elderly persons receiving a low-salt diet. A randomized, controlled trial.

BACKGROUND: Most nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit both cyclooxygenase-1 (COX-1), whose inhibition is associated with gastrointestinal ulceration, and COX-2, whose inhibition is associated with therapeutic benefits. Although agents that do not produce COX-1 activity may have fewer adverse effects, targeted disruption of the COX-2 allele in mice has resulted in severe renal problems, suggesting that COX-2 inhibition may also produce adverse effects. OBJECTIVE: To determine the effect of rofecoxib, a member of the coxib class of drugs and a specific inhibitor of the COX-2 enzyme, on renal function in elderly patients. DESIGN: A randomized, three-period, single-dose crossover study and a randomized, parallel-group, multiple-dose study. SETTING: Clinical research units. PATIENTS: 75 patients 60 to 80 years of age. INTERVENTION: In the first study, single doses of rofecoxib, 250 mg (about 5-fold to 20-fold the recommended dose); indomethacin, 75 mg; and placebo were administered to 15 patients. In the second study, multiple doses of rofecoxib, 12.5 or 25 mg/d; indomethacin, 50 mg three times daily; or placebo were administered to 60 patients. Patients in both studies received a low-sodium diet MEASUREMENTS: Glomerular filtration rate, creatinine clearance, and urinary and serum sodium and potassium values. RESULTS: Compared with placebo, single doses of rofecoxib and indomethacin decreased the glomerular filtration rate by 0.23 m/s (P < 0.001) and 0.18 mL/s (P = 0.003), respectively. In contrast, respective decreases of 0.14, 0.13, and 0.10 mL/s were observed after multiple doses of rofecoxib, 12.5 mg/d (P = 0.019); rofecoxib, 25 mg (P = 0.029), and indomethacin (P = 0.086) were administered. Changes in creatinine clearance and serum and urinary sodium and potassium were less pronounced. CONCLUSIONS: The effects of COX-2 inhibition on renal function are similar to those observed with nonselective NSAIDs. Thus, COX-2 seems to play an important role in human renal function.

Single-dose pharmacokinetics of nateglinide in subjects with hepatic cirrhosis.

This single-dose, open-label, parallel-group study compared the pharmacokinetics and tolerability of 120 mg doses of nateglinide, a physiologic mealtime glucose regulator for type 2 diabetes, in 8 subjects with cirrhosis and 8 matched healthy subjects. In both groups, plasma concentration peaked in a median of 0.5 hours, and mean terminal elimination half-lives were comparable. Mean +/- SD pharmacokinetic parameters in cirrhotic versus healthy subjects were slightly different (Cmax, 7.7 +/- 4.9 vs. 5.6 +/- 1.3 micrograms/ml; AUC(0-t), 18.5 +/- 7.5 vs. 14.2 +/- 2.1 micrograms.h/ml, respectively). Mean apparent total clearance and mean renal clearance in both groups were comparable. Mean protein-bound fractions were equivalent; binding appeared unaltered by metabolites. One cirrhotic and 2 healthy subjects each reported one adverse event. No statistically significant or clinically relevant alteration in pharmacokinetic parameters of nateglinide resulted from hepatic dysfunction, and it was well tolerated; therefore, adjustment of nateglinide dosage is not required in subjects with mild to moderate cirrhosis.

The pharmacokinetics of ziprasidone in subjects with normal and impaired hepatic function.

AIMS: To assess whether hepatic impairment influences the pharmacokinetics of ziprasidone. METHODS: Thirty subjects with normal hepatic function or a primary diagnosis of clinically significant cirrhosis (Child-Pugh A or B) were enrolled into an open-label, multicentre, multiple-dose study. The subjects with chronic, stable hepatic impairment and the matched control subjects received ziprasidone 40 mg day(-1), given orally with food, as two divided daily doses for 4 days and a single 20 mg dose on the morning of day 5. Pharmacokinetic variables were determined from multiple venous blood samples collected on days 1 and 5. Liver function was evaluated quantitatively using antipyrine. RESULTS: On day 1 there were no statistically significant differences in the pharmacokinetics (AUC(0,12 h), Cmax, tmax) of ziprasidone between the two groups. On day 5 there were no statistically significant differences in the Cmax or tmax for ziprasidone between the two groups. The mean AUC(0,12 h) for ziprasidone was statistically significantly greater in the hepatically impaired subjects compared with the normal subjects (590 ng ml(-1) h vs. 467 ng ml(-1) h, P = 0. 042). However, the AUC(0,12 h) increased by only 26% in the cirrhotic group compared with the matched control group. The ziprasidone lambda(z) in the subjects with normal hepatic function was statistically significantly greater than that in the hepatically impaired subjects (P<0.001). There was no correlation between antipyrine lambda(z) and ziprasidone lambda(z) in the subjects with normal hepatic function or in those with hepatic impairment. CONCLUSIONS: The findings of this study indicate that mild to moderate hepatic impairment does not result in clinically significant alteration of ziprasidone pharmacokinetics.