Clinical Pharmacology & Therapeutics (2003) 73 , P86–P86; doi:

Carvedilol is a relatively new drug with β‐and α1‐receptor blocking activity and antioxidant effects recently approved for the treatment of congestive heart failure (CHF). An ascending, multiple‐dose study was completed in 20 male patients with stable New York Heart Association (NYHA) Class III or IV CHF. The pharmacokinetics of carvedilol, S(−)‐carvedilol, R(+)‐carvedilol, and the active metabolites of carvedilol was assessed at steady state after twice‐daily oral administration of carvedilol for 7 days at 6.25, 12.5, 25, and 50 mg doses. Carvedilol exhibited stereoselective pharmacokinetics in CHF patients with dose‐proportional increases in steady‐state plasma concentrations of carvedilol and its enantiomers. Mean AUC and Cmax values for carvedilol were up to twofold higher in patients with Class IV CHF as compared to those with Class III CHF. Steady‐state plasma concentrations of the active metabolites also increased in a dose‐proportional manner and were typically 10% or less of that observed for carvedilol. In general, carvedilol was adequately tolerated by adult male CHF patients at the dose levels (6.25–50 mg) evaluated in this study as adverse events were consistent with those frequently observed in patients with CHF.

Eprosartan is an angiotensin II receptor antagonist being developed for the treatment of hypertension and heart failure. The effect of eprosartan on the steady‐state anticoagulant activity of warfarin was evaluated in 18 healthy male volunteers. Each subject's daily warfarin dose was titrated over 9 days to achieve a stable international normalized ratio (INR) of 1.3 to 1.6 by day 14. After the 14‐day warfarin titration phase, subjects were randomized to receive either eprosartan 300 mg or matching placebo twice a day for 7 days. All subjects continued to take the warfarin dose established during the 14‐day titration phase. The anticoagulant activity of warfarin was statistically equivalent when coadministered with eprosartan or with placebo. No serious or unexpected adverse events suggestive of abnormal bleeding occurred during coadministration of eprosartan and warfarin. As measured by the INR, there is no apparent effect of eprosartan on the anticoagulant effect of warfarin.

Eighteen healthy males received a single 300 mg oral dose of eprosartan as the commercial wet granulation formulation under fasting conditions and following a high-fat breakfast and a single 20 mg intravenous (i.v.) dose. The pharmacokinetics of i.v. eprosartan (mean±S.D.) were characterized by a low systemic plasma clearance (131.8±36.2 mL min−1) and a small steady-state volume of distribution (12.6±2.6 L). Oral bioavailability averaged 13.1%, due to incomplete absorption. In vitro dynamic flow cell dissolution data showed that pH-dependent aqueous solubility of eprosartan is one factor which limits absorption. Eprosartan terminal half-life was shorter after i.v. (approximately 2 h) versus oral (approximately 5–7 h) administration, which may be due to detection of an additional elimination phase or absorption rate-limited elimination following oral administration. Oral administration of eprosartan following a high-fat meal compared with fasting conditions resulted in a similar extent of absorption (based on AUC), but a decreased absorption rate. Cmax was approximately 25% lower, and a median delay of 1.25 h in time to Cmax was observed when eprosartan was administered with food. These minor changes in exposure are unlikely to be of clinical consequence; therefore, eprosartan may be administered without regard to meal times. © 1998 John Wiley & Sons, Ltd.

This was an open‐label, parallel group study to compare the pharmacokinetics of multiple oral doses of eprosartan in subjects with normal renal function (Clcr >80 mL/min; n = 8) and patients with mild (Clcr 60–80 mL/min; n = 8), moderate (Clcr 30–59 mL/min; n = 15), or severe (Clcr <30 mL/min; n = 3) renal insufficiency. Each subject received oral eprosartan 200 mg twice daily for 6 days and a single dose on day 7. Mean total maximum concentration (Cmax) and area under the concentration—time curve from 0 to 12 hours (AUC0–12) were similar for healthy subjects and those with mild renal impairment, but were an average of 25% to 35% and 51% to 55% greater for patients with moderate and severe renal impairment, respectively, compared with healthy subjects. Mean renal clearance (Clr), which was similar for healthy subjects and patients with mild renal impairment, was decreased an average of 41% and 95% in the groups with moderate and severe renal impairment, respectively, compared with normal subjects. Eprosartan was highly bound to plasma proteins in all groups; however, the unbound fraction was increased approximately two‐fold in the group with severe renal impairment. Mean unbound Cmax and AUC0–12 were an average of 53% to 61% and 185% to 210% greater for the patients with moderate and severe renal impairment, respectively, compared with healthy subjects. Headache was the most common adverse experience reported in all subgroups. Eprosartan was safe and well tolerated regardless of degree of renal impairment. Cmax and AUC were increased and renal clearance decreased in patients with moderate to severe renal impairment in comparison to healthy subjects and patients with mild renal impairment. However, based on the moderate renal clearance and known safety profile of eprosartan, it is not necessary to adjust the dose of eprosartan in patients with renal insufficiency.

AIMS:To compare the pharmacokinetics of eprosartan between young (18-45 years) and elderly (65 years) men and between young men and young, premenopausal women (18-45 years). METHODS:Twenty-four subjects (eight subjects/group) received a single 200 mg eprosartan oral dose followed by serial blood sampling over 24 h. RESULTS:Eprosartan was safe and well tolerated. There were no apparent differences in the pharmacokinetics of eprosartan between young females and young males or in the plasma protein binding of eprosartan (98%) for the three groups. On average, AUC (0,infinity) and Cmax values were approximately 2-fold higher in elderly men than young men [AUC (0,infinity) 95% CI: 1.22, 4.34; Cmax 95% CI: 0.98, 4.001. Similarly, unbound AUC (0,infinity) and Cmax values were, on average, approximately 2-fold higher in elderly men than young men [unbound AUC (0,infinity) 95% CI: 1.29, 4.44; unbound Cmax 95% CI: 1.02, 4.12]. tmax was delayed in the elderly men compared with young men, with a median difference of 2.5 h (95% CI: 1.00, 3.01 h). CONCLUSIONS:No gender differences were observed in the pharmacokinetics of eprosartan. There were approximately two fold higher AUC and Cmax values for eprosartan observed in elderly men as compared with young men, most likely due to increased bioavailability of eprosartan in the elderly. Based on the excellent safety profile in the elderly in Phase III clinical trials (doses up to 1200 mg eprosartan) eprosartan can be safely administered to elderly hypertensive patients without an initial dose adjustment. Subsequently, the dose of eprosartan, as for other antihypertensive agents, may be individualized based on tolerability/response.

Study Objective. To evaluate the pharmacokinetics and plasma protein binding of eprosartan in hepatic disease.Design. Single-dose, parallel-group study.Setting. Oklahoma Foundation for Digestive Research, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma.Patients. Eight healthy subjects with normal hepatic function and eight patients with hepatic disease.Intervention. All subjects received a single oral dose of eprosartan 100 mg.Measurements and Main Results. Eprosartan plasma concentrations were quantified by high-performance liquid chromatography; plasma protein binding was determined by ultrafiltration. Using analysis of variance, point estimates (PE) and 90% CIs were calculated. Total and unbound maximum concentrations and degree of plasma protein binding were similar for both groups. Total area under the plasma concentration-time curve (AUC(0-t)) was approximately 40% higher for the group with hepatic disease (PE 1.42, 90% CI 0.94-2.14). Similarly, unbound AUC(0-t) was approximately 50% higher (PE 1.53, 90% CI 0.98-2.39).Conclusion. Eprosartan was safe and well tolerated by both groups. Based on the increase in AUC in patients with hepatic disease compared with those with normal hepatic function, the dosage of eprosartan in patients with hepatic disease should be individualized based on tolerability and response.

AIMS:To study the effect of eprosartan, a nonbiphenyl tetrazole angiotensin II receptor antagonist, on digoxin pharmacokinetics in a randomized, open-label, two period, period balanced crossover study in 12 healthy men.METHODS:Each subject received a single 0.6 mg oral dose of digoxin (Lanoxicaps 0.2 mg/capsule, Glaxo Wellcome) alone or following 4 days of dosing with eprosartan 200 mg orally every 12 h. Each study period was separated by a 14 day washout interval. Serial blood samples were obtained for up to 96 h after each digoxin dose for determination of digoxin pharmacokinetics. The effect of eprosartan on digoxin pharmacokinetics was assessed through an equivalence-type approach using AUC(0, t') as the primary endpoint.RESULTS:For AUC(0, t'), the ratio of digoxin+eprosartan: digoxin alone was 0.99 with a 90% confidence interval (CI) of [0.90, 1.09]. For Cmax, the ratio was 1.00 with a 90% CI of [0.86, 1.17]. tmax was similar for both regimens. Both regimens were safe and well tolerated.CONCLUSIONS:Based on AUC and Cmax data, it can be concluded that eprosartan has no effect on the pharmacokinetics of a single oral dose of digoxin.

The cardiovascular effects of granisetron given as a 30-second i.v. bolus dose and of granisetron and ondansetron given by currently recommended methods were studied. Healthy adults 18 to 50 years of age were randomly assigned to one of four treatments during each of four study periods: granisetron 10 micrograms/kg (as the hydrochloride salt) i.v. over 5 minutes, granisetron 10 micrograms/kg i.v. over 30 seconds, ondansetron 32 mg (as the hydrochloride salt) i.v. over 15 minutes, and placebo. During each study period, the researchers gave each subject three sequential injections using a double-blind, double-dummy technique. Each subject was to receive all four regimens. Two resting 12-lead electrocardiograms (ECGs) were obtained before the regimen, and one was obtained at the end of each injection and at intervals up to 24 hours after the third injection. Sitting blood pressure and pulse were measured before treatments, immediately after the end of each injection, and at intervals up to 24 hours after injection 3. Safety data were analyzed for 13 subjects, and ECG interval data for 12 of them. The mean postdose QTc interval differed significantly among regimens. There were no other significant regimen-associated differences among the four mean results for any ECG interval. The mean post-dose QTc interval for ondansetron was significantly greater than that for each of the other regimens. The drug regimens were comparable in safety and tolerability. A total of 20 adverse effects, all mild to moderate, were reported in 10 subjects. Changes in vital signs were minimal. There were no clinically important cardiovascular changes associated with the i.v. administration of granisetron 10 micrograms/kg over 30 seconds, granisetron 10 micrograms/kg over 5 minutes, or ondansetron 32 mg over 15 minutes in healthy adults.

Clinical Pharmacology & Therapeutics (1996) 59, 201–201; doi: 10.1038/sj.clpt.1996.304

Single ascending doses of RSHZ19 (also known as SB 209763), a humanized monoclonal antibody (MAb) directed to the fusion protein of respiratory syncytial virus, were administered to healthy men to evaluate the safety, pharmacokinetics, antigenicity, and fusion inhibition (FI) activity of RSHZ19. Doses of RSHZ19 (0.025-10.0 mg/kg) or placebo were infused over 30 min, and subjects were followed for 10 weeks. Plasma concentrations of RSHZ19 and RSHZ19-specific antibodies were determined by ELISAs. FI titers were used to evaluate the ability of plasma to inhibit virus-induced fusion of VERO cells previously infected with RS Long strain virus. Twenty-six subjects, mean age 24, completed the study. RSHZ19 was safe and well tolerated, and no subject developed antibodies to RSHZ19 during follow-up. RSHZ19 had low plasma clearance and a half-life of approximately 23 days, similar to native IgG. Increases in FI titers relative to pretreatment levels were seen 24 h after MAb administration in all 4 subjects given 10 mg/kg and in 2 of 4 given 5 mg/kg.