GS-9857 in patients with chronic hepatitis C virus genotype 1-4 infection: a randomized, double-blind, dose-ranging phase 1 study.

GS-9857, an inhibitor of the hepatitis C virus (HCV) nonstructural protein (NS) 3/4A, demonstrates potent activity against HCV genotypes 1-6 and improved coverage against commonly encountered NS3 resistance-associated variants (RAVs). In this study, the safety, tolerability, antiviral activity and pharmacokinetics (PK) of GS-9857 were evaluated in patients with chronic HCV genotype 1-4 infection. Patients with genotype 1-4 infection received placebo or once-daily GS-9857 at doses ranging from 50 to 300 mg for 3 days under fasting conditions. GS-9857 was well tolerated; all reported adverse events (AEs) were mild or moderate in severity. Diarrhoea and headache were the most commonly reported AEs. Grade 3 or 4 laboratory abnormalities were observed in 17% of patients receiving GS-9857; there were no Grade 3 or 4 abnormalities in alanine aminotransferase, aspartate aminotransferase or alkaline phosphatase levels. GS-9857 demonstrated potent antiviral activity in patients with chronic HCV infection, achieving mean and median maximum reductions in HCV RNA of ≥3 log10 IU/mL following administration of a 100-mg dose in patients with HCV genotype 1a, 1b, 2, 3 or 4 infection. The antiviral activity of GS-9857 was unaffected by the presence of pretreatment NS3 RAVs. In patients with genotype 1-4 infection, GS-9857 exhibited linear PK and was associated with a median half-life of 29-42 h, supporting once-daily dosing. Thus, the tolerability, efficacy and pharmacokinetic profile of GS-9857 support its further evaluation for treatment of patients with chronic HCV infection.

A phase 1, randomized, dose-ranging study of GS-5816, a once-daily NS5A inhibitor, in patients with genotype 1-4 hepatitis C virus.

GS-5816 is an inhibitor of the hepatitis C virus (HCV) NS5A protein that has demonstrated pan-genotypic activity and a high barrier to resistance in HCV replicon assays. The aim of this study was to evaluate the safety, antiviral activity and pharmacokinetics of once-daily doses of GS-5816 in patients with genotype 1-4 HCV infection. Patients with genotype 1-4 HCV infection were randomized to 3 days of GS-5816 at doses ranging from 5 to 150 mg or placebo. Adverse events were recorded, and plasma samples obtained for analysis of pharmacokinetics, HCV RNA and NS5A sequencing studies. GS-5816 5-150 mg for 3 days was well tolerated and resulted in rapid declines in HCV RNA that were sustained over the dosing period. In patients treated with the 150 mg dose of GS-5816, the mean maximal HCV RNA declines were 4.0, 4.0, 4.4, 3.3 and 3.5 log10 IU/mL in patients with genotype 1a, 1b, 2, 3 and 4 HCV infection, respectively. Pretreatment NS5A resistance-associated polymorphisms were detected in 31% (22/70) of patients. Genotype 1 and 3 HCV-infected patients without pretreatment NS5A resistance-associated polymorphisms had greater declines in HCV RNA than patients with resistance-associated polymorphisms. Plasma pharmacokinetics were supportive of once-daily dosing. GS-5816 demonstrated pangenotypic antiviral activity in patients with genotype 1-4 HCV infection. It will be further evaluated in combination with other pangenotypic direct-acting antivirals to achieve the goal of developing a well-tolerated, highly effective treatment for all HCV genotypes.

Pharmacokinetics of tedizolid in subjects with renal or hepatic impairment.

Two open-label, single-dose, parallel-group studies were conducted to characterize the pharmacokinetics of the novel antibacterial tedizolid and the safety of tedizolid phosphate, its prodrug, in renally or hepatically impaired subjects. Tedizolid pharmacokinetics in subjects with severe renal impairment without dialysis support was compared with that of matched control subjects with normal renal function. Effects of hemodialysis on tedizolid pharmacokinetics were determined in a separate cohort of subjects undergoing long-term hemodialysis. Effects of hepatic impairment on tedizolid pharmacokinetics were determined in subjects with moderate or severe hepatic impairment and compared with those of matched control subjects with normal hepatic function. Each participant received a single oral (hepatic impairment) or intravenous (renal impairment) dose of tedizolid phosphate at 200 mg; hemodialysis subjects received two doses (separated by 7 days), before and after dialysis, in a crossover fashion. The pharmacokinetics of tedizolid was similar in subjects with severe renal impairment and controls (∼8% lower area under the concentration-time curve [AUC], with a nearly identical peak concentration) and in subjects undergoing hemodialysis before and after tedizolid phosphate administration (∼9% lower AUC, with a 15% higher peak concentration); <10% of the dose was removed during 4 h of hemodialysis. Tedizolid pharmacokinetics was only minimally altered in subjects with moderate or severe hepatic impairment; the AUC was increased approximately 22% and 34%, respectively, compared with that of subjects in the control group. Tedizolid phosphate was generally well tolerated in all participants. These results suggest that tedizolid phosphate dose adjustments are not necessary in patients with any degree of renal or hepatic impairment. (This study has been registered at ClinicalTrials.gov under registration numbers NCT01452828 [renal study] and NCT01431833 [hepatic study].).

An evaluation of the pharmacokinetics of treprostinil diolamine in subjects with hepatic impairment.

WHAT IS KNOWN AND OBJECTIVE: Treprostinil diolamine (oral treprostinil) is a prostacyclin analogue under evaluation for the treatment for pulmonary arterial hypertension (PAH). This study assessed the pharmacokinetics (PK) and safety of treprostinil following oral administration of a single sustained-release 1 mg dose in subjects with hepatic impairment. METHODS: Four cohorts, including healthy volunteers, and subjects with mild, moderate and severe hepatic impairment were enrolled. Thirty subjects completed the study. Mean treprostinil clearance values (CL/F) decreased with the severity of hepatic impairment. The decrease in CL/F resulted in a marked increase in exposure levels of treprostinil. Relative to healthy subjects, mean area under the curve from time zero to 24 h after dosing interval (AUC0-24) values in subjects with mild, moderate and severe hepatic impairment increased by approximately 2·2-, 4·9- and 7·6-fold, respectively. The most frequent adverse events (AEs) exhibited in this study were similar to those seen with prostacyclin and its analogues and with AEs seen in other clinical studies with oral treprostinil (e.g. headache, diarrhoea and nausea). The overall incidence of all AEs and the specific events of headache and nausea increased with severity of hepatic impairment. WHAT IS NEW AND CONCLUSION: Based on these results, dosage adjustments should be performed in subjects with hepatic impairment.

The pharmacokinetics of peginterferon alfa-2a and ribavirin in African American, Hispanic and Caucasian patients with chronic hepatitis C.

BACKGROUND: Amongst Caucasian, Hispanic and African Americans with genotype 1 hepatitis C virus (HCV), there is a wide variation in response to treatment with peginterferon alfa-2a (PEG-IFN alfa-2a) and ribavirin. AIM: To evaluate the pharmacokinetics (PK) of PEG-IFN alfa-2a and ribavirin among these three groups. METHODS: Forty-seven patients with genotype 1 CHC (17 African Americans, 14 Hispanics and 16 Caucasians) received 8 weeks of PEG-IFN alfa-2a (180 µg/week) and ribavirin (1000 or 1200 mg/day). PEG-IFN alfa-2a serum concentrations and ribavirin plasma concentrations were measured following the first dose and at week 8. Pharmacokinetic parameters (C(max), T(max), AUC, CL/F) were estimated using noncompartmental methods. RESULTS: There was no difference in the pharmacokinetic parameters for PEG-IFN alfa-2a following single-dose or steady-state administration between African American or Hispanic patients compared with Caucasian patients. Ribavirin pharmacokinetic parameters were similar between Hispanic and Caucasian patients for single-dose and steady-state administration. The single-dose C(max) was 33% lower (P < 0.05) in African American compared with Caucasian patients. Other ribavirin single-dose and steady-state pharmacokinetic parameters were slightly decreased (approximately 20% lower) in African American patients, but were not considered clinically meaningful. CONCLUSIONS: No differences were observed in PEG-IFN alfa-2a pharmacokinetic parameters between African American or Hispanic patients compared with Caucasian patients. For ribavirin, no differences were observed in pharmacokinetic parameters between Hispanic and Caucasian patients. While a trend towards increased ribavirin clearance and decreased exposure was observed in African American patients vs. Caucasian patients, the differences were small and not considered clinically meaningful (Clinical Trial Number: NP17354).

Pharmacokinetics and pharmacodynamics of tonapofylline in subjects with severe renal impairment and in elderly subjects.

OBJECTIVE: The study was conducted to characterize the pharmacokinetics and pharmacodynamics of tonapofylline in subjects with severe renal impairment and in elderly subjects. METHOD: Subjects with severe renal impairment were matched demographically with healthy subjects. Elderly subjects with normal renal function for their ages were also enrolled. All subjects (n = 8 per group) received a single intravenous administration of tonapofylline at 1 mg/kg. RESULTS: The pharmacokinetics of tonapofylline was not significantly different in subjects with severe renal impairment, or in elderly subjects, as compared to healthy subjects. Among all pharmacokinetic parameters, the only statistically significant difference was observed for Cmax between the healthy and the severe renal impairment groups, which was 21% and considered clinically insignificant. Pharmacodynamic assessment demonstrated the natriuretic effects of tonapofylline across groups, with little accompanying kaliuresis. No change in renal function occurred after single dose of tonapofylline, despite substantial increases in excretion of urinary sodium. Single 1 mg/kg intravenous administration of tonapofylline was generally safe. CONCLUSION: The pharmacokinetics of tonapofylline in subjects with severe renal impairment and elderly subjects with normal renal function for age is similar to that in healthy subjects. It has been demonstrated in all groups that tonapofylline has natriuretic effects and is able to maintain renal function, which can be beneficial to patients with congestive heart failure.

A pilot study to examine the feasibility of insulin glargine in subjects with impaired fasting glucose, impaired glucose tolerance or new-onset type 2 diabetes.

OBJECTIVE: People with early type 2 diabetes and pre-diabetes (impaired glucose tolerance [IGT] and/or impaired fasting glucose [IFG]) are at risk of hyperglycaemia-related complications, including cardiovascular disease. Insulin, traditionally reserved as late treatment in type 2 diabetes, may also be a useful therapy in this population. We examined the short-term efficacy and tolerability of insulin glargine (glargine) in individuals with early or pre-type 2 diabetes. RESEARCH DESIGN AND METHODS: In this multicentre, double-blind, placebo-controlled, randomized, parallel group, 12-day study, subjects with IGT/IFG (n=9), newly diagnosed type 2 diabetes (n=9) or normal glucose tolerance (n=3) (confined to a clinical research unit taking a prescribed diet) were randomized to once-daily glargine (n=16) or placebo (saline; n=5) at bedtime. Dose was titrated to achieve target fasting blood glucose (FBG) 80-95 mg/dL. RESULTS: Over the treatment period, mean FBG decreased in glargine-treated subjects (from 100.0+/-18.8 to 85.6+/-18.4 mg/dL), but was unchanged in placebo-treated subjects (from 112.5+/-10.6 to 111.3+/-17.5 mg/dL). Mean eight-point blood glucose value decreased by 9.7 mg/dL in the glargine group, but increased by 8.1 mg/dL in the placebo group. Mean post-exercise blood glucose was similar before and after glargine treatment, but increased after placebo treatment. Five subjects receiving glargine experienced 16 mild symptomatic hypoglycaemia episodes; however, no hypoglycaemia occurred during exercise. Mean body weight decreased in both the glargine (-0.44 kg) and placebo (-0.25 kg) groups, in line with dietary restrictions. CONCLUSIONS: The results of this pilot study suggest that glargine can be used by people with IFG, IGT or new-onset type 2 diabetes for management of hyperglycaemia with low risk of hypoglycaemia. However titration of insulin in people on dietary restrictions should be more cautious as they may be more prone to hypoglycaemia. Further studies are warranted to determine the clinical benefits of this approach.

Raltegravir thorough QT/QTc study: a single supratherapeutic dose of raltegravir does not prolong the QTcF interval.

Raltegravir is a novel HIV-1 integrase inhibitor with potent in vitro activity (IC(95) = 31 nM in 50% human serum). A double-blind, randomized, placebo-controlled, double-dummy, 3-period, single-dose crossover study was conducted; subjects received single oral doses of 1600 mg raltegravir, 400 mg moxifloxacin, and placebo. The upper limit of the 2-sided 90% confidence interval for the QTcF interval placebo-adjusted mean change from baseline of raltegravir was less than 10 ms at every time point. For the raltegravir and placebo groups, there were no QTcF values >450 ms or change from baseline values >30 ms. A mean C(max) of approximately 20 muM raltegravir was attained, approximately 4-fold higher than the C(max) at the clinical dose. Moxifloxacin demonstrated an increase in QTcF at the 2-, 3-, and 4-hour time points. Administration of a single supratherapeutic dose of raltegravir does not prolong the QTcF interval. A single supratherapeutic dose design may be appropriate for crossover thorough QTc studies.

Posaconazole pharmacokinetics, safety, and tolerability in subjects with varying degrees of chronic renal disease.

Posaconazole is a triazole antifungal in development for the treatment of invasive fungal infections. The authors evaluated the pharmacokinetics and safety of posaconazole in healthy subjects and in those with mild (CL(CR) = 50-80 mL/min), moderate (CL(CR) = 20-49 mL/min), and severe chronic renal disease (CL(CR) <20 mL/min; receiving outpatient hemodialysis) (n = 6/group). Subjects received one 400-mg dose of posaconazole oral suspension with a standardized high-fat breakfast. For hemodialysis-dependent subjects, this dose was given on a nonhemodialysis day, and a second 400-mg dose was given 6 hours before hemodialysis. Blood samples were collected before dose and up to 120 hours postdose. For hemodialysis-dependent subjects following the second dose, additional samples (predialyzed and postdialyzed) were collected before, during, and after dialysis. There was no correlation between posaconazole pharmacokinetics and mild to moderate renal disease; the slopes of the linear regressions for creatinine clearance versus posaconazole AUC, C(max), CL/F, and t1/2 values were not significantly different from zero (P > .130). Mean CL/F values before and during hemodialysis were comparable. Furthermore, the difference in the predialyzed and postdialyzed posaconazole concentrations was only approximately 3%, supporting that posaconazole was not removed by hemodialysis. Protein binding was similar in all groups (approximately 98%) and was unaffected by hemodialysis. Posaconazole was generally well tolerated. One patient had elevated liver function test results that were not present at baseline and were thought to be possibly related to posaconazole. Results of this single-dose study indicate that dosage adjustments for patients with varying degrees of renal disease are not required.

Antihypertensive efficacy and safety of olmesartan medoxomil compared with amlodipine for mild-to-moderate hypertension.

The antihypertensive efficacy of the angiotensin II receptor blocker olmesartan medoxomil has been shown to compare favourably with that of other antihypertensive agents. This randomized, double-blind study compared the antihypertensive efficacy of the starting dose of olmesartan medoxomil with that of the calcium channel blocker amlodipine besylate (amlodipine) in subjects with mild-to-moderate hypertension. Following a 4-week, single-blind, placebo run-in period, 440 subjects aged >/=18 years were randomized to the starting dose of olmesartan medoxomil (20 mg/day), amlodipine (5 mg/day), or placebo for 8 weeks. Subjects were evaluated by 24-h ambulatory blood pressure monitoring (ABPM) and by seated cuff blood pressure (BP) measurements at trough. The primary end point was the change from baseline in mean 24-h diastolic blood pressure (DBP) by ABPM at Week 8. Secondary end points included change from baseline in mean 24-h ambulatory systolic blood pressure (SBP) at 8 weeks, change from baseline in mean seated trough cuff DBP and SBP measurements, and response and control rates for DBP <90 and <85 mmHg. Control rates for SBP <140 and <130 mmHg were also calculated. Olmesartan medoxomil and amlodipine produced significantly greater reductions in ambulatory and seated DBP and SBP compared with placebo. Mean reductions in ambulatory and seated BP were similar between the two active agents; however, in the olmesartan medoxomil group, significantly more patients achieved the SBP goal of <130 mmHg and the DBP goal of <85 mmHg. Both drugs were well tolerated at the recommended starting dose. Although amlodipine was associated with a higher incidence of oedema, this did not reach statistical significance. Olmesartan medoxomil is an effective antihypertensive agent, with BP-lowering efficacy at the starting dose similar to that of amlodipine, and is associated with more patients achieving the rigorous BP goals of SBP <130 mmHg and DBP <85 mmHg.

Evaluation of the pharmacokinetic profiles of the new testosterone topical gel formulation, Testim, compared to AndroGel.

A two-period, randomized, complete crossover study was performed to evaluate the pharmacokinetic profiles of Testim (AA2500), a new 1% testosterone topical gel formulation, compared to AndroGel, an already available 1% testosterone topical gel. Twenty-nine hypogonadal subjects received a single dose (50 mg testosterone) of each formulation seven days apart. C(max) estimates for total testosterone, dihydrotestosterone and free testosterone were greater (30, 19 and 38%, respectively) following the application of Testim compared to AndroGel. Similarly, AUC(0-24) estimates for total testosterone, dihydrotestosterone, and free testosterone were greater (30, 11 and 47%, respectively) following the application of Testim compared to AndroGel. Confidence intervals for C(max) and AUC(0-24) were not wholly contained within the bioequivalence limits for testosterone, therefore Testim trade mark and AndroGel are not bioequivalent with Testim providing higher serum levels and greater bioavailability than AndroGel.

Cardiovascular safety of sublingual apomorphine in patients on stable doses of oral antihypertensive agents and nitrates.

Sublingual (SL) apomorphine (2 to 6 mg) has been shown to be effective for treatment of male erectile dysfunction. Many patients with erectile dysfunction are also being treated for systemic hypertension and/or cardiovascular disease. In a double-blind, randomized, placebo-controlled, crossover trial, SL apomorphine 5 mg and placebo were administered on alternate days to 162 men who were on long-term therapy (> or =4 weeks) with angiotensin-converting enzyme inhibitors, beta blockers, diuretics, calcium channel blockers, alpha(1) blockers, or short- or long-acting nitrates. Blood pressure and heart rate were measured before and after dosing; cardiac rhythm was recorded by 4-hour Holter monitoring. The only potentially clinically significant interactions between SL apomorphine and the antihypertensive agents or short-acting nitrates were greater orthostatic decreases in systolic blood pressure in the alpha-blocker and calcium channel blocker groups (-10 and -6 mm Hg vs placebo, respectively). Administration of SL apomorphine after dosing with long-acting nitrates resulted in significant decreases in blood pressure when patients were standing (mean systolic change, -5 to -9 mm Hg 30 to 60 minutes postdose, p <0.05; mean diastolic change, -3 to -4 mm Hg 50 to 60 minutes postdose, p <0.05). The most common adverse events with SL apomorphine were dizziness, nausea, and headache. Syncope occurred in 1 patient in the beta-blocker group; symptomatic hypotension occurred in 2 patients each in the short- and long-acting nitrate groups. Thus, in patients receiving common antihypertensive agents and short-acting nitrates, as well as in most patients receiving long-acting nitrates, SL apomorphine at higher than recommended doses produced no clinically significant changes in heart rate or blood pressure greater than changes seen with SL apomorphine alone.

Comparative efficacy of olmesartan, losartan, valsartan, and irbesartan in the control of essential hypertension.

In a multicenter, randomized, double-blind trial, the authors compared the antihypertensive efficacy of once-daily treatment with the new angiotensin II type 1 receptor blocker (ARB) olmesartan (20 mg) with recommended starting doses of losartan (50 mg), valsartan (80 mg), and irbesartan (150 mg) in 588 patients with a cuff diastolic blood pressure (DBP) of greater than or equal to 100 and less than or equal to 115 mm Hg and a mean daytime DBP of greater than or equal to 90 mm Hg and less than 120 mm Hg, as measured by ambulatory blood pressure monitoring. Cuff and ambulatory blood pressures were monitored at baseline and after 8 weeks of treatment. All groups were predominantly white and approximately 62% male, and their mean age was approximately 52 years. In all groups, mean baseline DBP and systolic blood pressure (SBP) were approximately 104 and 157 mm Hg, respectively. The reduction of sitting cuff DBP with olmesartan (11.5 mm Hg), the primary efficacy variable of this study, was significantly greater than with losartan, valsartan, and irbesartan (8.2, 7.9, and 9.9 mm Hg, respectively). Reductions of cuff SBP with the four ARBs ranged from 8.4-11.3 mm Hg and were not significantly different. The reduction in mean 24-hour DBP with olmesartan (8.5 mm Hg) was significantly greater than reductions with losartan and valsartan (6.2 and 5.6 mm Hg, respectively) and showed a trend toward significance when compared to the reduction in DBP with irbesartan (7.4 mm Hg; p=0.087). The reduction in mean 24-hour SBP with olmesartan (12.5 mm Hg) was significantly greater than the reductions with losartan and valsartan (9.0 and 8.1 mm Hg, respectively) and equivalent to the reduction with irbesartan (11.3 mm Hg). All drugs were well tolerated. The authors conclude that olmesartan, at its starting dose, is more effective than the starting doses of the other ARBs tested in reducing cuff DBP in patients with essential hypertension.

Safety and efficacy of short-duration oral terbinafine for the treatment of tinea corporis or tinea cruris in subjects with HIV infection or diabetes.

Cutaneous fungal infections in immunocompromised patients can be aggressive and difficult to treat. To determine the safety and efficacy of oral terbinafine for the treatment of tinea corporis or tinea cruris in subjects with human immunodeficiency virus (HIV) infection or diabetes, 2 prospective, randomized, open-label studies were conducted in general community and referral centers. HIV-positive (n = 6) and diabetic patients (n = 8) between the ages of 18 and 75 years diagnosed with either tinea corporis or tinea cruris, as confirmed by potassium hydroxide (KOH) wet mount microscopy, were randomized to receive either 1 or 2 weeks of the antifungal treatment. Patients received oral terbinafine 250 mg once daily for 1 or 2 weeks. Main outcome measures were mycological cure, determined at week 6 for HIV-positive and diabetic patients. Three subjects were excluded from the efficacy analyses because of negative cultures at screening (n = 2) and lack of follow-up cultures (n = 1). Efficacy results were similar between the 1- and 2-week groups in both studies. All HIV-positive subjects and 83% of diabetic subjects achieved mycological cures at week 6 based on culture results. In a safety population that included all randomized patients (N = 14), no subject experienced adverse events or significant changes in laboratory findings related to study medication. Results of these small series indicate that a short course of oral terbinafine 250 mg once daily is a safe and effective treatment for tinea corporis or tinea cruris in subjects with HIV infection or diabetes.

A prospective, randomized, open-label trial comparing telmisartan 80 mg with valsartan 80 mg in patients with mild to moderate hypertension using ambulatory blood pressure monitoring.

OBJECTIVE: To compare the antihypertensive efficacy and tolerability of telmisartan 80 mg with valsartan 80 mg throughout a 24 h dosing interval. DESIGN: A prospective, randomized, open-label, blinded end point, parallel group study. Treatment efficacy was compared using ambulatory blood pressure monitoring (ABPM), cuff sphygmomanometry and calculated responder rates. Tolerability was assessed by physical examination, laboratory parameters, 12-lead electrocardiogram, blood pressure and heart rate monitoring, and evaluation of adverse events. SETTING: Thirty-five centres in the United States. PATIENTS: Four hundred and twenty-six patients with mild to moderate essential hypertension entered the study. Ninety-two per cent (n=393) completed the study. INTERVENTIONS: Patients underwent a four-week, single-blind, placebo run-in period before being randomly assigned to once-daily oral telmisartan 80 mg (n=214) or valsartan 80 mg (n=212) for an eight-week, open-label treatment period. RESULTS: Treatment with telmisartan was associated with a significantly greater mean reduction from baseline in the last 6 h ABPM mean for diastolic blood pressure compared with the valsartan-treated group (-7.5+/-0.6 mmHg versus -5.2+/-0.6 mmHg, respectively, P<0.01). Secondary analyses showed significantly greater efficacy with telmisartan 80 mg than with valsartan 80 mg, including greater mean reductions from baseline of ABPM (systolic blood pressure and diastolic blood pressure) during the daytime (06:00 to 21:59) and morning (06:00 to11:59) hours, and larger decreases in trough cuff blood pressure (P<0.01). Both treatments showed placebo-like tolerability profiles. CONCLUSIONS: Telmisartan 80 mg once daily was superior to valsartan 80 mg once daily in reducing diastolic blood pressure during the last 6 h of the 24 h dosing interval. These results may be due to telmisartan's longer plasma half-life or to a higher potency compared with valsartan, such that a higher dose of valsartan may produce effects similar to those of 80 mg telmisartan. These data confirm the long duration of action of telmisartan with consistent and sustained control of blood pressure over 24 h and during the last 6 h of the dosing interval. Both treatments were well tolerated; the adverse event data confirmed the excellent tolerability profiles of telmisartan and valsartan that have been reported previously.

Atrial natriuretic factor in oliguric acute renal failure. Anaritide Acute Renal Failure Study Group.

Atrial natriuretic peptide (ANP), an endogenous hormone synthesized by the cardiac atria, has been shown to improve renal function in multiple animal models of acute renal failure. In a recent multicenter clinical trial of 504 patients with acute tubular necrosis (oliguric and nonoliguric), ANP decreased the need for dialysis only in the oliguric patients. In the present study, 222 patients with oliguric acute renal failure were enrolled into a multicenter, randomized, double-blind, placebo-controlled trial designed to assess prospectively the safety and efficacy of ANP compared with placebo. Subjects were randomized to treatment with a 24-hour infusion of ANP (anaritide, 0.2 microgram/kg/min; synthetic form of human ANP) or placebo. Dialysis and mortality status were followed up for 60 days. The primary efficacy end point was dialysis-free survival through day 21. Dialysis-free survival rates were 21% in the ANP group and 15% in the placebo group (P = 0.22). By day 14 of the study, 64% and 77% of the ANP and placebo groups had undergone dialysis, respectively (P = 0.054), and 9 additional patients (7 patients, ANP group; 2 patients, placebo group) needed dialysis but did not receive it. Although a trend was present, there was no statistically significant beneficial effect of ANP in dialysis-free survival or reduction in dialysis in these subjects with oliguric acute renal failure. Mortality rates through day 60 were 60% versus 56% in the ANP and placebo groups, respectively (P = 0.541). One hundred two of 108 (95%) versus 63 of 114 (55%) patients in the ANP and placebo groups had systolic blood pressures less than 90 mm Hg during the study-drug infusion (P < 0.001). The maximal absolute decrease in systolic blood pressure was significantly greater in the anaritide group than placebo group (33.6 versus 23.9 mm Hg; P < 0.001). This well-characterized population with oliguric acute renal failure had an overall high morbidity and mortality.

Influence of renal function on the pharmacokinetics of cerivastatin in normocholesterolemic adults.

OBJECTIVE: The influence of impaired renal function on the pharmacokinetics of single and multiple doses of cerivastatin was evaluated in this nonrandomized, non-blinded, 7-day, multiple-dose study. METHODS: Thirty-five adults between the ages of 21 years and 75 years with normal renal function (CL(CR) >90 ml/min/1.73 m2, n = 9), or patients with either mild (CL(CR) 61 ml/min/1.73 m2 to < or =90 ml/min/1.73 m2, n = 9), moderate (CL(CR) 30 ml/min/1.73 m2 to < or =60 ml/ min/1.73 m2, n = 8), or severe (CL(CR) <30 ml/min/ 1.73 m2, but not on dialysis, n = 9) renal impairment were given cerivastatin 0.3 mg daily each evening for 7 days. The steady-state pharmacokinetics of cerivastatin, including the area under the concentration-time curve (AUC)0-24, peak plasma concentration (Cmax), time to reach Cmax (tmax) and elimination half-life (t1/2), were determined on day 1 and day 7. The logarithm of the pharmacokinetic variables was analyzed using analysis of variance (ANOVA). Safety assessments included physical examination, fundoscopy, vital signs, electrocardiogram (ECG), adverse events, and laboratory safety indices. RESULTS: The day-1 AUC in patients with mild renal impairment was similar to that of patients with normal function (19.6 microg/h/l vs 19.2 microg/h/l, respectively). However, the AUC for cerivastatin patients with moderate or severe renal impairment was 40-60% higher (30.8 microg/h/l and 29.0 microg/h/l, respectively). Cmax values for patients with normal, mild, moderate, and severe renal impairment were 3.3, 3.4, 4.6, and 5.2 microg/l, respectively. This modest increase in plasma cerivastatin levels is nearly equivalent to a 0.4-mg daily dose, which has been recently approved in the United States. The mean t1/2 of cerivastatin was less than 4.5 h in all patients, indicating that renal dysfunction did not promote cerivastatin accumulation. This observation was confirmed by the finding that the cerivastatin plasma levels on day 1 and day 7 were similar in all patient groups. Furthermore, the mean AUC and Cmax values for both demethylated and hydroxylated cerivastatin were similar in the patients with the most severe renal dysfunction to the corresponding values in healthy subjects. Cerivastatin was well tolerated in all patients irrespective of renal function. Adverse events were observed in 37% of the subjects; nearly all were mild and generally of short duration, and most resolved without intervention. Incidence of adverse events was similar across all three renal groups and the control group. There were no clinically significant laboratory changes other than those consistent with renal disease. CONCLUSION: This study demonstrates that dosage adjustment of the daily 0.3-mg cerivastatin dose in patients with significant renal impairment is likely unnecessary.

Pharmacokinetics of repaglinide in subjects with renal impairment.

OBJECTIVE: To evaluate the effect of renal impairment and renal failure on the pharmacokinetics and safety of repaglinide. METHODS: We conducted a phase I, multicenter, parallel-group, pharmacokinetic comparison trial with single and multiple doses of repaglinide in subjects with various degrees of renal impairment. Subjects with normal renal function (n = 6) and subjects with renal impairment (mild to moderate, n = 6; severe, n = 6) received treatment with 2 mg repaglinide for 7 days. Subjects in the hemodialysis group (n = 6) received two single doses of 2 mg repaglinide separated by a 7- to 14-day washout period. All subjects had repaglinide serum pharmacokinetic profiles measured for the first and last doses administered. Serum steady-state levels, urine levels, and dialysate levels were also measured. RESULTS: Pharmacokinetic parameters did not show significant changes after single or multiple doses of repaglinide, although the elimination rate constant in the group with severe renal impairment decreased after 1 week of treatment. Subjects with severe impairment had significantly higher area under the curve values after single and multiple doses of repaglinide than subjects with normal renal function. No significant differences in values for maximum serum concentration or time to reach maximum concentration were detected between subjects with renal impairment and those with normal renal function. Hemodialysis did not significantly affect repaglinide clearance. CONCLUSIONS: Repaglinide was safe and well tolerated in subjects with varying degrees of renal impairment. Although adjustment of starting doses of repaglinide is not necessary for renal impairment or renal failure, severe impairment may require more care when upward adjustments of dosage are made.

Long-term safety and antihypertensive efficacy of irbesartan: pooled results of five open-label studies.

An analysis of 5 multicenter, open-label studies was conducted to evaluate the long-term safety and efficacy of irbesartan in 1,006 patients with seated diastolic blood pressure (SeDBP) 95-110 mm Hg. Irbesartan monotherapy was started at 75 mg and titrated to 300 mg at 2- to 4-week intervals to achieve normalized blood pressure (SeDBP <90 mm Hg). If normalized BP was not attained with irbesartan 300 mg alone, adjunctive medications could be added. At 12 months of therapy, the mean reduction in seated systolic blood pressure/SeDBP was 21.0/15.8 mm Hg, and 83% (684/821) of patients were normalized. Of those normalized, 64% were receiving irbesartan monotherapy and 86% were receiving irbesartan or irbesartan/hydrochlorothiazide only. No evidence of tachyphylaxis to the antihypertensive effect of irbesartan was noted. Thus, long-term irbesartan therapy, with or without other antihypertensives, achieved and maintained normalized BP in the majority of patients and was well tolerated.

Flexible prandial glucose regulation with repaglinide in patients with type 2 diabetes.

Repaglinide is a novel, rapid-acting prandial glucose regulator. To investigate the effect of repaglinide, 1 mg before each meal, in maintaining glycaemic control in Type 2 diabetic patients who either miss a meal or have an extra meal, 25 patients were randomized to either a fixed-meal regimen of three meals/day or one of two mixed-meal regimens consisting of repeating patterns of two, three or four meals/day over a 20-day period. On the 21st day each patient received three meals. Overall glycaemic control was assessed by weekly serum fructosamine concentrations and 13-point and 37-point serum glucose profiles. Mean fructosamine concentrations decreased significantly to normal values during the treatment period (from 3.10 to 2.68 mg/dl on the fixed-meal regimen and from 3.37 to 2.85 mg/dl on the mixed-meal regimens; P < 0.05), with no statistically significant difference in glucose control between the fixed-meal and mixed-meal regimen groups. Fasting serum glucose levels decreased slightly in both groups, but were not altered by the number of meals consumed. Similarly, serum glucose profiles were not altered significantly by the number of meals consumed. Repaglinide was well tolerated, and no hypoglycaemic events were reported. Serum cholesterol levels were significantly reduced (P < 0.05) in both the fixed-meal and mixed-meal groups, as were triglyceride levels in the mixed-meal group (P < 0.05). It was concluded that meal-associated treatment with repaglinide was well tolerated irrespective of the number of meals consumed/day. Thus, since missing or postponing a meal is a realistic scenario for many individuals, repaglinide offers an oral anti-diabetic treatment which can be adjusted to suit each individual's lifestyle.