Marion Dahlke

A randomized, double-blind, placebo-controlled, multicentre study to assess haemodynamic effects of serelaxin in patients with acute heart failure

Aims The aim of this study was to evaluate the haemodynamic effects of serelaxin (30 µg/kg/day 20-h infusion and 4-h post-infusion period) in patients with acute heart failure (AHF). Methods and results This double-blind, multicentre study randomized 71 AHF patients with pulmonary capillary wedge pressure (PCWP) ≥18 mmHg, systolic blood pressure (BP) ≥115 mmHg, and estimated glomerular filtration rate ≥30 mL/min/1.73 m2 to serelaxin (n = 34) or placebo (n = 37) within 48 h of hospitalization. Co-primary endpoints were peak change from baseline in PCWP and cardiac index (CI) during the first 8 h of infusion. Among 63 patients eligible for haemodynamic analysis (serelaxin, n = 32; placebo, n = 31), those treated with serelaxin had a significantly higher decrease in peak PCWP during the first 8 h of infusion (difference vs. placebo: −2.44 mmHg, P = 0.004). Serelaxin showed no significant effect on the peak change in CI vs. placebo. Among secondary haemodynamic endpoints, a highly significant reduction in pulmonary artery pressure (PAP) was observed throughout the serelaxin infusion (largest difference in mean PAP vs. placebo: −5.17 mmHg at 4 h, P < 0.0001). Right atrial pressure, systemic/pulmonary vascular resistance, and systolic/diastolic BP decreased from baseline with serelaxin vs. placebo and treatment differences reached statistical significance at some time points. Serelaxin administration improved renal function and decreased N-terminal pro-brain natriuretic peptide levels vs. placebo. Treatment with serelaxin was well tolerated with no apparent safety concerns. Conclusion The haemodynamic effects of serelaxin observed in the present study provide plausible mechanistic support for improvement in signs and symptoms of congestion observed with this agent in AHF patients. ClinicalTrials.gov identifier NCT01543854.

Renal Hemodynamic Effects of Serelaxin in Patients With Chronic Heart Failure: A Randomized, Placebo-Controlled Study

Background—Serelaxin is a promising therapy for acute heart failure. The renal hemodynamic effects of serelaxin in patients with chronic heart failure are unknown. Methods and Results—In this double-blind, randomized, placebo-controlled, multicenter study, patients with New York Heart Association Class II to III chronic heart failure, left ventricular ejection fraction ⩽45%, and estimated glomerular filtration rate (GFR) 30 to 89 mL/min per 1.73 m2 received intravenous serelaxin 30 &mgr;g/kg per day or placebo for 24 hours. Primarily, we assessed the difference between serelaxin and placebo on renal plasma flow (para-aminohippuric acid clearance) and GFR (iothalamate clearance) over 8 to 24 hours. All 22 patients from 1 clinical site were excluded from primary analyses before unblinding because of implausible measurements. The primary analysis comprised 65 patients, mean age was 68 (±10) years, 89% were male, mean estimated GFR was 64 (±19) mL/min per 1.73 m2, and 34% had New York Heart Association Class III symptoms. Renal plasma flow increased by 29% with serelaxin and 14% with placebo (13% relative increase with serelaxin; P=0.0386), whereas GFR changes did not differ significantly during 8 to 24 hours. Filtration fraction increased by 36% with serelaxin and 62% with placebo (16% relative decrease with serelaxin; P=0.0019) during 8 to 24 hours. Changes in systolic blood pressure were largely similar, and creatinine clearance did not differ between groups. Adverse event rates were similar with serelaxin (20.5%) and placebo (25.0%). Conclusions—In patients with chronic heart failure, serelaxin increased renal plasma flow and reduced the increase in filtration fraction compared with placebo, but did not affect GFR. These results suggest beneficial renal hemodynamic effects in patients with chronic heart failure. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01546532.

Aliskiren penetrates adipose and skeletal muscle tissue and reduces renin-angiotensin system activity in obese hypertensive patients

Objective: In animals, the direct renin inhibitor aliskiren showed extensive tissue binding in the kidney and long-lasting renal effects. Aliskiren provides prolonged blood pressure-lowering effects following treatment discontinuation in patients. Therefore, we investigated whether aliskiren attains tissue concentrations sufficient to inhibit local renin–angiotensin system (RAS) activity in patients. Methods: We included 10 hypertensive patients with abdominal adiposity in an open-label study. Following 1–2 weeks washout, patients received 2 weeks placebo, then 4 weeks aliskiren 300 mg once daily, followed by 4 weeks washout, and then 4 weeks amlodipine 5 mg once daily. Drug concentrations and RAS biomarkers were measured in interstitial fluid using microdialysis and in biopsies from abdominal subcutaneous adipose and skeletal muscle. Results: We detected aliskiren in all compartments. After 4 weeks of treatment, microdialysate aliskiren concentrations (ng/ml) were 2.4 ± 2.1 (adipose) and 7.1 ± 4.2 (skeletal muscle), similar to plasma concentrations (8.4 ± 4.4); tissue concentrations (ng/g) were 29.0 ± 16.7 (adipose) and 107.3 ± 68.6 (skeletal muscle). Eight weeks after discontinuation, aliskiren was measurable in tissue biopsies but not in plasma or in interstitial fluid. Pooled microdialysate samples from two sets of four patients suggested reduction in tissue angiotensin II with aliskiren but not with amlodipine. Conclusion: In obese hypertensive patients, aliskiren penetrates adipose and skeletal muscle tissue at levels that are apparently sufficient to reduce tissue RAS activity. Furthermore, tissue binding may contribute to aliskirens prolonged blood pressure-lowering effect following discontinuation.

Safety and tolerability of serelaxin, a recombinant human relaxin-2 in development for the treatment of acute heart failure, in healthy Japanese volunteers and a comparison of pharmacokinetics and pharmacodynamics in healthy Japanese and Caucasian populations

Serelaxin, a recombinant form of the human relaxin‐2 hormone, is currently under clinical investigation for treatment of acute heart failure. This double‐blind, placebo‐controlled, dose‐ranging study investigated the effect of Japanese ethnicity on the pharmacokinetics (PK), pharmacodynamics (PD), and safety and tolerability of serelaxin. Japanese healthy subjects (n = 32) received 10, 30, or 100 µg/kg/day of serelaxin, or placebo, administered as a 48‐hour intravenous infusion. A Caucasian cohort (n = 8) receiving 30 µg/kg/day open‐label serelaxin was included for comparison. In all subjects, serum serelaxin concentrations increased rapidly after the start of infusion, approached steady state as early as 4 hours, and declined rapidly upon treatment cessation. Serum exposure to serelaxin increased with increasing doses. Statistical dose proportionality was shown for AUCinf over the entire dose range. A significant increase in estimated glomerular filtration rate from baseline to Day 2 (30 and 100 µg/kg/day) and to Day 3 (10 and 100 µg/kg/day) was observed compared with placebo. Serelaxin was well tolerated by all subjects. In conclusion, PK, PD, and safety profiles of serelaxin were generally comparable between Japanese and Caucasian subjects, suggesting that no dose adjustment will be required in Japanese subjects during routine clinical use of this agent.

Pharmacokinetics of serelaxin in patients with hepatic impairment: a single-dose, open-label, parallel group study.

AIMS Serelaxin is a recombinant form of human relaxin-2 in development for treatment of acute heart failure. This study aimed to evaluate the pharmacokinetics (PK) of serelaxin in patients with hepatic impairment. Secondary objectives included evaluation of immunogenicity, safety and tolerability of serelaxin. METHODS This was an open-label, parallel group study (NCT01433458) comparing the PK of serelaxin following a single 24 h intravenous (i.v.) infusion (30 μg kg(-1)  day(-1) ) between patients with mild, moderate or severe hepatic impairment (Child-Pugh class A, B, C) and healthy matched controls. Blood sampling and standard safety assessments were conducted. Primary non-compartmental PK parameters [including area under the serum concentration-time curve AUC(0-48 h) and AUC(0-∞) and serum concentration at 24 h post-dose (C24h )] were compared between each hepatic impairment group and healthy controls. RESULTS A total of 49 subjects (including 25 patients with hepatic impairment) were enrolled, of which 48 subjects completed the study. In all groups, the serum concentration of serelaxin increased over the first few hours of infusion, reached steady-state at 12-24 h and then declined following completion of infusion, with a mean terminal half-life of 7-8 h. All PK parameter estimates were comparable between each group of patients with hepatic impairment and healthy controls. No serious adverse events, discontinuations due to adverse events or deaths were reported. No serelaxin treatment-related antibodies developed during this study. CONCLUSIONS The PK and safety profile of serelaxin were not affected by hepatic impairment. No dose adjustment is needed for serelaxin treatment of 48 h i.v. infusion in patients with hepatic impairment.

Effect of Verapamil on the Pharmacokinetics of Aliskiren in Healthy Participants

The authors describe the drug‐drug interaction between aliskiren and verapamil in healthy participants. Eighteen participants first received an oral dose of aliskiren 300 mg (highest recommended clinical dose) in period 1. After a 10‐day washout period, the participants received verapamil 240 mg/d for 8 days (period 2). On day 8, the participants also received an oral dose of aliskiren 300 mg. Safety and pharmacokinetic analyses were performed during each treatment period. Concomitant administration of a single dose of aliskiren during steady‐state verapamil resulted in an increase in plasma concentration of aliskiren. The mean increase in AUC0‐∞, AUClast, and Cmax was about 2‐fold. On day 8, in the presence of aliskiren, AUCτ,ss of R‐norverapamil, R‐verapamil, S‐norverapamil, and S‐verapamil was decreased by 10%, 16%, 10%, and 25%, respectively. Similarly, the Cmax,ss of R‐norverapamil, R‐verapamil, S‐norverapamil, and S‐verapamil was decreased by 13%, 18%, 12%, and 24%, respectively. Aliskiren did not affect the AUCτ,ss ratios of R‐norverapamil/R‐verapamil and S‐norverapamil/S‐verapamil. Aliskiren administered alone or in combination with verapamil was well tolerated in healthy participants. In conclusion, no dose adjustment is necessary when aliskiren is administered with moderate ABCB1 inhibitors such as verapamil (240 mg/d).

Pharmacokinetic drug-drug interaction assessment of LCZ696 (an angiotensin receptor neprilysin inhibitor) with omeprazole, metformin or levonorgestrel-ethinyl estradiol in healthy subjects.

LCZ696 is a novel angiotensin receptor neprilysin inhibitor in development for the treatment of cardiovascular diseases. Here, we assessed the potential for pharmacokinetic drug‐drug interaction of LCZ696 (400 mg, single dose or once daily [q.d.]) when co‐administered with omeprazole 40 mg q.d. (n = 28) or metformin 1000 mg q.d. (n = 27) or levonorgestrel‐ethinyl estradiol 150/30 μg single dose (n = 24) in three separate open‐label, single‐sequence studies in healthy subjects. Pharmacokinetic parameters of LCZ696 analytes (sacubitril, LBQ657, and valsartan), metformin, and levonorgestrel‐ethinyl estradiol were assessed. Omeprazole did not alter the AUCinf of sacubitril and pharmacokinetics of LBQ657; however, 7% decrease in the Cmax of sacubitril, and 11% and 13% decreases in AUCinf and Cmax of valsartan were observed. Co‐administration of LCZ696 with metformin had no significant effect on the pharmacokinetics of LBQ657 and valsartan; however, AUCtau,ss and Cmax,ss of metformin were decreased by 23%. Co‐administration of LCZ696 with levonorgestrel‐ethinyl estradiol had no effect on the pharmacokinetics of ethinyl estradiol and LBQ657 or AUCinf of levonorgestrel. The Cmax of levonorgestrel decreased by 15%, and AUCtau,ss and Cmax,ss of valsartan decreased by 14% and 16%, respectively. Co‐administration of LCZ696 with omeprazole, metformin, or levonorgestrel‐ethinyl estradiol was not associated with any clinically relevant pharmacokinetic drug interactions.

Pharmacokinetics of serelaxin in patients with severe renal impairment or end‐stage renal disease requiring hemodialysis: A single‐dose, open‐label, parallel‐group study

Serelaxin, a recombinant human relaxin‐2 hormone, is in clinical development for treating acute heart failure. This open‐label, parallel‐group study investigated serelaxin pharmacokinetics (PK) after a single 4‐hour intravenous infusion (10 µg/kg) in patients with severe renal impairment (n = 6) or end‐stage renal disease (ESRD) requiring hemodialysis (PK on the day of dialysis [n = 6] or during dialysis‐free interval [n = 6]), compared with matched healthy subjects (n = 18). In all participants, serum serelaxin concentration peaked at the end of infusion and subsequently declined with mean terminal elimination half‐life of 6.5–8.8 hours. Compared with healthy subjects, a moderate decrease in serelaxin systemic clearance (37%–52%) and increase in its exposure (30%–115%) were observed in all patients. During the 4‐hour hemodialysis in ESRD patients, 30% serelaxin was removed, with hemodialysis clearance constituting approximately 52% of total systemic clearance. Serelaxin was well tolerated with no deaths, serious adverse events (AE), or AE‐related discontinuations. Antiserelaxin antibodies were not detected in any participant. Given the shallow dose‐response relationship observed with serelaxin in clinical studies and its wide therapeutic window, the observed PK differences in patients with severe renal impairment compared with healthy subjects are unlikely to pose a safety risk and do not warrant a predefined dosage adjustment in such patients.

Proportional pulse pressure relates to cardiac index in stabilized acute heart failure patients

ABSTRACT Aims: In chronic heart failure, proportional pulse pressure (PPP) is suggested as an estimate of cardiac index (CI). The association between CI and PPP in acute heart failure (AHF) has not been described. Methods: This was examined using hemodynamic measurements (from a trial using serelaxin) in 63 stabilized AHF patients. Results: Mean (SD) age was 68 (11), 74% male, mean (SD) ejection fraction (EF) was 33.4% (13.7), mean (SD) CI (L/min/m2) was 2.3 (0.6). CI correlated with PPP (Pearson R = 0.42; p < 0.0001) based on a linear mixed-effects model analysis of 171 pairs of measurements from 47 patients (out of 63) where CI and PPP were measured within 3 min of each other during. Serelaxin treatment did not modify the established correlation between CI and PPP. Time-weighted average CI correlated with time-weighted average PPP (Spearman Rank R = 0.35; p = 0.0051) over the −4 h to 24 h time interval. In a multivariable regression analysis, low PPP was an independent predictor of low CI (p < 0.0001). Conclusions: In patients with AHF after initial clinical stabilization, both baseline and post-baseline CI measurements are positively related to PPP. This was the most closely related non-invasive blood pressure variable to CI.

Population pharmacokinetics of serelaxin in patients with acute or chronic heart failure, hepatic or renal impairment, or portal hypertension and in healthy subjects

Serelaxin is a recombinant human relaxin‐2 peptide being developed for the treatment of acute heart failure (AHF). The present analyses aimed to evaluate serelaxin pharmacokinetics following intravenous administration and to identify covariates that may explain pharmacokinetic variability in healthy subjects and patients.