Serelaxin, recombinant human relaxin-2, for treatment of acute heart failure (RELAX-AHF): a randomised, placebo-controlled trial.

BACKGROUND: Serelaxin, recombinant human relaxin-2, is a vasoactive peptide hormone with many biological and haemodynamic effects. In a pilot study, serelaxin was safe and well tolerated with positive clinical outcome signals in patients with acute heart failure. The RELAX-AHF trial tested the hypothesis that serelaxin-treated patients would have greater dyspnoea relief compared with patients treated with standard care and placebo. METHODS: RELAX-AHF was an international, double-blind, placebo-controlled trial, enrolling patients admitted to hospital for acute heart failure who were randomly assigned (1:1) via a central randomisation scheme blocked by study centre to standard care plus 48-h intravenous infusions of placebo or serelaxin (30 µg/kg per day) within 16 h from presentation. All patients had dyspnoea, congestion on chest radiograph, increased brain natriuretic peptide (BNP) or N-terminal prohormone of BNP, mild-to-moderate renal insufficiency, and systolic blood pressure greater than 125 mm Hg. Patients, personnel administering study drug, and those undertaking study-related assessments were masked to treatment assignment. The primary endpoints evaluating dyspnoea improvement were change from baseline in the visual analogue scale area under the curve (VAS AUC) to day 5 and the proportion of patients with moderate or marked dyspnoea improvement measured by Likert scale during the first 24 h, both analysed by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00520806. FINDINGS: 1161 patients were randomly assigned to serelaxin (n=581) or placebo (n=580). Serelaxin improved the VAS AUC primary dyspnoea endpoint (448 mm × h, 95% CI 120-775; p=0·007) compared with placebo, but had no significant effect on the other primary endpoint (Likert scale; placebo, 150 patients [26%]; serelaxin, 156 [27%]; p=0·70). No significant effects were recorded for the secondary endpoints of cardiovascular death or readmission to hospital for heart failure or renal failure (placebo, 75 events [60-day Kaplan-Meier estimate, 13·0%]; serelaxin, 76 events [13·2%]; hazard ratio [HR] 1·02 [0·74-1·41], p=0·89] or days alive out of the hospital up to day 60 (placebo, 47·7 [SD 12·1] days; serelaxin, 48·3 [11·6]; p=0·37). Serelaxin treatment was associated with significant reductions of other prespecified additional endpoints, including fewer deaths at day 180 (placebo, 65 deaths; serelaxin, 42; HR 0·63, 95% CI 0·42-0·93; p=0·019). INTERPRETATION: Treatment of acute heart failure with serelaxin was associated with dyspnoea relief and improvement in other clinical outcomes, but had no effect on readmission to hospital. Serelaxin treatment was well tolerated and safe, supported by the reduced 180-day mortality. FUNDING: Corthera, a Novartis affiliate company.

Neutrophil-to-Lymphocyte Ratio and Outcomes in Patients Admitted for Acute Heart Failure (As Seen in the BLAST-AHF, Pre-RELAX-AHF, and RELAX-AHF Studies).

Previous studies have suggested that the neutrophil-to-lymphocyte ratio (NLR) is a novel yet readily evaluable inflammatory biomarker that may be useful for determining cardiovascular prognosis during acute episodes. The study investigated the role of NLR in predicting cardiovascular (CV) outcomes in patients with acute heart failure (HF). Individual patient data from the BLAST-AHF (phase 2b study of the biased ligand of the angiotensin 2 type 1 receptor, TRV027), Pre-RELAX-AHF (phase 2b study of recombinant human relaxin-2, serelaxin), and RELAX-AHF (phase 3 study of serelaxin) randomized, placebo-controlled studies for patients with acute HF were pooled for analysis. Dyspnea visual analog scale area under the curve through day 5, worsening HF through day 5, 30-day all-cause mortality, 60-day HF/renal failure rehospitalizations or CV death, 180-day all-cause mortality, and 180-day CV death were assessed. There were several differences in the baseline characteristics of the patients divided by NLR tertile, with patients in the higher NLR having worse clinical characteristics. NLR was an independent predictor of 30-day all-cause mortality (adjusted hazard ratio [HR] per log2 NLR increment: 1.66 [1.22 to 2.25], p = 0.001), 60-day HF/renal failure rehospitalizations or CV death: 1.33 [1.12 to 1.57], p = 0.001), 180-day all-cause mortality (adjusted HR 1.27 [1.08 to 1.50], p = 0.003), and 180-day CV death (adjusted HR 1.24 [1.04 to 1.49], p = 0.018). NLR, a readily available inflammatory biomarker, was associated with independent risk for short- and long-term adverse outcomes in acute HF, surpassing traditional markers, such as natriuretic peptides.

Site enrollment rate, outcomes, and study drug effects in a multicenter trial. Results from RELAX-AHF.

BACKGROUND: Site selection is critical in acute heart failure trials. We assessed whether the enrollment rate per site affects patients' characteristics, outcomes and treatment response. METHODS AND RESULTS: A total of 1161 patients enrolled at 96 sites in the RELAX-AHF trial (serelaxin vs placebo) were included. Annualized enrollment rate was calculated as the total number of patients enrolled at each site divided by time that the site was open (patients per year). Sites were classified in low (<10), medium (10-20) and high enrolling sites (>20 patients per site/year) and were compared for prognosis and serelaxin effect. High enrolling sites were more prevalent in Eastern Europe and Israel. Time from hospital admission to randomization was shorter in high enrolling sites (6.3±4.4h>20 patients sites versus 8.7±4.5h for <10 patients sites; p<0.0001). Patients had slightly fewer comorbidities, lower levels of natriuretic peptides and creatinine and more severe pulmonary congestion in high enrolling sites. Use of evidence-based therapies was higher in high enrolling sites. The rates of worsening heart failure to day 5, 180-day cardiovascular and all-cause mortality and 60-day heart failure/renal failure rehospitalization or cardiovascular death, were similar across study groups even after adjustment for covariates. The effects of serelaxin on these outcomes did not differ by enrollment rate. CONCLUSIONS: Characteristics of RELAX-AHF study patients enrolled in high versus low enrolling sites differed only slightly and there were no differences in outcomes. Differences in serelaxin effects by enrollment rate were not discernible.

A multimarker multi-time point-based risk stratification strategy in acute heart failure: results from the RELAX-AHF trial.

AIMS: We evaluated the added prognostic value of a multi-time point-based multimarker panel of biomarkers in patients with acute heart failure (AHF). METHODS AND RESULTS: Seven circulating biomarkers [NT-proBNP, high sensitivity cardiac troponin T (hs-cTnT), soluble ST2 (sST2), growth differentiation factor 15 (GDF-15), cystatin-C, galectin-3, and high sensitivity C-reactive protein (hs-CRP)] were measured at baseline and on days 2, 5, 14, and 60 in 1161 patients enrolled in the RELAX-AHF trial. Patients with BNP ≥350 ng/L or NT-proBNP ≥1400 ng/L, mild to moderate renal impairment, and systolic blood pressure >125 mmHg were included in the trial. Time-dependent Cox regression analysis was utilized to evaluate the incremental value of serial measurement of biomarkers. Added value of individual biomarkers and their combination, on top of a pre-specified baseline model, was quantified with the gain in the C-index. Serial biomarker evaluation showed incremental predictive value over baseline measurements alone for the prediction of 180-day cardiovascular mortality except for galectin-3. While a repeat measurement as early as day 2 was adequate for NT-proBNP and cystatin-C in terms of maximizing discriminatory accuracy, further measurements on days 14 and 60 provided added value for hs-cTnT, GDF-15, sST2, and hs-CRP. Individual biomarker additions on top of the baseline model showed additional prognostic value. The greatest prognostic gain was, however, attained with the combination of NT-proBNP, hs-cTnT, GDF-15, and sST2, which yielded 0.08 unit absolute increment in the C-index to 0.87 (95% confidence interval 0.83-0.91]. CONCLUSION: In patients with AHF and mild to moderate renal impairment, a multimarker approach based on a panel of serially evaluated biomarkers provides the greatest prognostic improvement unmatched by a single time point-based single marker strategy.

Effects of serelaxin in acute heart failure patients with renal impairment: results from RELAX-AHF.

BACKGROUND: Serelaxin showed beneficial effects on clinical outcome and trajectories of renal markers in patients with acute heart failure. We aimed to study the interaction between renal function and the treatment effect of serelaxin. METHODS: In the current post hoc analysis of the RELAX-AHF trial, we included all patients with available estimated glomerular filtration rate (eGFR) at baseline (n = 1132). Renal impairment was defined as an eGFR <60 ml/min/1.73 m(2) estimated by creatinine. RESULTS: 817 (72.2 %) patients had a baseline eGFR <60 ml/min/1.73 m(2). In placebo-treated patients, baseline renal impairment was related to a higher 180 day cardiovascular (HR 3.12, 95 % CI 1.33-7.30) and all-cause mortality (HR 2.81, 95 % CI 1.34-5.89). However, in serelaxin-treated patients, the risk of cardiovascular and all-cause mortality was less pronounced (HR 1.19, 95 % CI 0.54 -2.64; p for interaction = 0.106, and HR 1.15 95 % CI 0.56-2.34 respectively; p for interaction = 0.088). In patients with renal impairment, treatment with serelaxin resulted in a more pronounced all-cause mortality reduction (HR 0.53, 95 % CI 0.34-0.83), compared with patients without renal impairment (HR 1.30, 95 % CI 0.51-3.29). CONCLUSION: Renal dysfunction was associated with higher cardiovascular and all-cause mortality in placebo-treated patients, but not in serelaxin-treated patients. The observed reduction in (cardiovascular) mortality in RELAX-AHF was more pronounced in patients with renal dysfunction. These observations need to be confirmed in the ongoing RELAX-AHF-2 trial.

Growth differentiation factor 15 (GDF-15) in patients admitted for acute heart failure: results from the RELAX-AHF study.

BACKGROUND: Growth differentiation factor 15 (GDF-15) was found to be upregulated in patients with chronic heart failure (HF) and associated with disease severity, however, data on patients with acute heart failure (AHF) is lacking. METHODS AND RESULTS: Levels of GDF-15 were measured at pre-specified time-points (baseline and at days 2, 5, 14, and 60) in patients enrolled in the placebo-controlled RELAXin in Acute Heart Failure (RELAX-AHF) study, which examined the effect of serelaxin in 1161 patients with AHF, systolic blood pressure >125 mmHg, and mild to moderate renal impairment. Neither baseline nor changes in GDF-15 were associated with the degree of dyspnoea or dyspnoea relief. After adjustment for baseline characteristics, baseline GDF-15 was not associated with the composite endpoint of heart failure or renal failure (HF/RF) readmission at 60 days/cardiovascular (CV) death or CV death at 180 days. In contrast, larger increases in GDF-15 levels at days 2 and 14 were associated with a greater risk of 60-day HF/RF rehospitalizations/CV death and CV death at 180 days. Serelaxin treatment was associated with significantly larger decreases of GDF-15 at days 2 and 5 than placebo. CONCLUSIONS: In AHF patients enrolled in the RELAX-AHF study, increases in GDF-15 levels, but not baseline measurements, were associated with a greater likelihood of adverse outcomes. Serelaxin administration was associated with greater decreases in GDF-15 compared with placebo.

Effect of serelaxin on mode of death in acute heart failure: results from the RELAX-AHF study.

BACKGROUND: Little is known about mode of death after acute heart failure (AHF) hospitalization. In the RELAX-AHF (Efficacy and Safety of Relaxin for the Treatment of Acute Heart Failure) study, serelaxin, the recombinant form of human relaxin-2, reduced post-discharge mortality at 180 days in selected patients with AHF. OBJECTIVES: The goal of this study was to assess the effect of serelaxin on specific modes of death in patients with AHF. METHODS: The RELAX-AHF study randomized 1,161 patients with AHF to 48 h of therapy with intravenous serelaxin or placebo. Patients were followed for vital status through 180 days. A blinded clinical events committee reviewed all deaths and adjudicated a cause of death on the basis of pre-specified criteria. Cox proportional hazard models were used to assess the effect of serelaxin on each mode of death, on the basis of pre-specified groupings of mode of death. RESULTS: There were 107 deaths (9.3%): 37 (35%) due to HF, 25 (23%) due to sudden death, 15 (14%) due to other cardiovascular (CV) causes, 19 (18%) due to non-CV causes, and 11 (10%) classified as unknown. The treatment effect of serelaxin was most pronounced on other CV deaths (hazard ratio [HR]: 0.29; 95% CI: 0.12 to 0.73; p = 0.005) and sudden death (HR: 0.46; 95% CI: 0.20 to 1.07; p = 0.065). There was no apparent impact of serelaxin treatment on HF deaths or non-CV deaths. CONCLUSIONS: In the RELAX-AHF study, the effects of serelaxin on mortality were primarily driven by reduction in mortality from other CV causes and sudden death, without apparent impact on HF deaths. (Efficacy and Safety of Relaxin for the Treatment of Acute Heart Failure [RELAX-AHF]; NCT00520806).