Safety and Efficacy of Vocacapsaicin for Management of Postsurgical Pain: A Randomized Clinical Trial.

BACKGROUND: Nonopioid management of postsurgical pain remains a major unmet need. Few studies have evaluated TRPV1 agonists for analgesia after surgery. We studied intraoperative vocacapsaicin, a novel prodrug of the TRPV1 agonist capsaicin, in a validated model of postsurgical pain. METHODS: This was a triple-blinded, randomized, placebo-controlled, dose-ranging trial in patients undergoing bunionectomy. We randomized patients 1:1:1:1 to surgical site administration of 14 mL of placebo or one of three vocacapsaicin concentrations: 0.30, 0.15, or 0.05 mg/mL. The prespecified primary endpoint was the area-under-the-curve of the Numerical Rating Scale (NRS) pain score at rest through 96 hours for the 0.3 mg/mL group. Prespecified ordered, secondary endpoints for the 0.3 mg/mL group included percent of patients who did not require opioids from 0-96 hours, total opioid consumption through 96 hours, and the area-under-the-curve of the NRS pain score for the first week. RESULTS: We randomized 147 patients. During the first 96 hours, vocacapsaicin 0.30 mg/mL reduced pain at rest by 33% vs. placebo (primary endpoint, 95% CI [10%, 52%], effect size (Cohen's D) = 0.61, p = 0.005). Twenty-six percent of patients receiving vocacapsaicin 0.30 mg/mL did not require postoperative opioids for analgesia (p=0.025) vs. 5% of patients receiving placebo. Vocacapsaicin 0.30 mg/mL reduced opioid consumption over the first 96 hours by 50% vs. placebo (95% CI [26%, 67%], effect size = 0.76, p = 0.002). Vocacapsaicin 0.30 mg/mL reduced pain over the first week by 37% vs. placebo (95% CI [12%, 57%], effect size = 0.62, p = 0.004). Treatment effect persisted for at least 2 weeks. All study endpoints showed an administered concentration vs. response relationship. Vocacapsaicin was well-tolerated with no differences between groups in any safety parameter. CONCLUSIONS: A single, local administration of vocacapsaicin during surgery reduced pain and opioid consumption for at least 96 hours after surgery compared to control. TRIAL REGISTRATION: ClinicalTrials.gov NCT03599089.

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.

Effects of danicamtiv, a novel cardiac myosin activator, in heart failure with reduced ejection fraction: experimental data and clinical results from a phase 2a trial.

AIMS: Both left ventricular (LV) and left atrial (LA) dysfunction and remodelling contribute to adverse outcomes in heart failure with reduced ejection fraction (HFrEF). Danicamtiv is a novel, cardiac myosin activator that enhances cardiomyocyte contraction. METHODS AND RESULTS: We studied the effects of danicamtiv on LV and LA function in non-clinical studies (ex vivo: skinned muscle fibres and myofibrils; in vivo: dogs with heart failure) and in a randomized, double-blind, single- and multiple-dose phase 2a trial in patients with stable HFrEF (placebo, n = 10; danicamtiv, n = 30; 50-100 mg twice daily for 7 days). Danicamtiv increased ATPase activity and calcium sensitivity in LV and LA myofibrils/muscle fibres. In dogs with heart failure, danicamtiv improved LV stroke volume (+10.6 mL, P < 0.05) and LA emptying fraction (+10.7%, P < 0.05). In patients with HFrEF (mean age 60 years, 25% women, ischaemic heart disease 48%, mean LV ejection fraction 32%), treatment-emergent adverse events, mostly mild, were reported in 17 patients (57%) receiving danicamtiv and 4 patients (40%) receiving placebo. Danicamtiv (at plasma concentrations ≥2000 ng/mL) increased stroke volume (up to +7.8 mL, P < 0.01), improved global longitudinal (up to -1.0%, P < 0.05) and circumferential strain (up to -3.3%, P < 0.01), decreased LA minimal volume index (up to -2.4 mL/m2 , P < 0.01) and increased LA function index (up to 6.1, P < 0.01), when compared with placebo. CONCLUSIONS: Danicamtiv was well tolerated and improved LV systolic function in patients with HFrEF. A marked improvement in LA volume and function was also observed in patients with HFrEF, consistent with pre-clinical findings of direct activation of LA contractility.

Effects of serelaxin in patients admitted for acute heart failure: a meta-analysis.

AIMS: The effectiveness and safety of 48 h intravenous 30 µg/kg/day serelaxin infusion in acute heart failure (AHF) has been studied in six randomized, controlled clinical trials. METHODS AND RESULTS: We conducted a fixed-effect meta-analysis including all studies of intravenous serelaxin initiated within the first 16 h of admission for AHF. Endpoints considered were the primary and secondary endpoints examined in the serelaxin phase III studies. In six randomized controlled trials, 6105 total patients were randomized to receive intravenous serelaxin 30 µg/kg/day and 5254 patients to control. Worsening heart failure to day 5 occurred in 6.0% and 8.1% of patients randomized to serelaxin and control, respectively (hazard ratio 0.77, 95% confidence interval 0.67-0.89; P = 0.0002). Serelaxin had no statistically significant effect on length of stay, or cardiovascular death, or heart or renal failure rehospitalization. Serelaxin administration resulted in statistically significant improvement in markers of renal function and reductions in both N-terminal pro-B-type natriuretic peptide and troponin. No significant adverse outcomes were noted with serelaxin. Through the last follow-up, which occurred at an average of 4.5 months (1-6 months), serelaxin administration was associated with a reduction in all-cause mortality, with an estimated hazard ratio of 0.87 (95% confidence interval 0.77-0.98; P = 0.0261). CONCLUSIONS: Administration of intravenous serelaxin to patients admitted for AHF was associated with a highly significant reduction in the risk of 5-day worsening heart failure and in changes in renal function markers, but not length of stay, or cardiovascular death, or heart or renal failure rehospitalization. Serelaxin administration was safe and associated with a significant reduction in all-cause mortality.

Cardiac Myosin Activation with Gene Therapy Produces Sustained Inotropic Effects and May Treat Heart Failure with Reduced Ejection Fraction.

Chronic inotropic therapy is effective for the treatment of heart failure with reduced ejection fraction, but has been limited by adverse long-term safety profiles, development of tolerance, and the need for chronic parenteral administration. A safe and convenient therapeutic agent that produces sustained inotropic effects could improve symptoms, functional capacity, and quality of life. Small amounts of 2-deoxy-adenosine triphosphate (dATP) activate cardiac myosin leading to enhanced contractility in normal and failing heart muscle. Cardiac myosin activation triggers faster myosin crossbridge cycling with greater force generation during each contraction. This paper describes the rationale and results of a translational medicine effort to increase dATP levels using a gene therapy strategy to deliver and upregulate ribonucleotide reductase (R1R2), the enzyme responsible for dATP synthesis, selectively in cardiomyocytes. In small and large animal models of heart failure, a single dose of this gene therapy has led to sustained inotropic effects with a benign safety profile. Further animal studies are appropriate with the goal of testing this agent in patients with heart failure.

Translation of Cardiac Myosin Activation with 2-deoxy-ATP to Treat Heart Failure via an Experimental Ribonucleotide Reductase-Based Gene Therapy.

Despite recent advances, chronic heart failure remains a significant and growing unmet medical need, reaching epidemic proportions carrying substantial morbidity, mortality, and costs. A safe and convenient therapeutic agent that produces sustained inotropic effects could ameliorate symptoms, and improve functional capacity and quality of life. We discovered small amounts of 2-deoxy-ATP (dATP) activate cardiac myosin leading to enhanced contractility in normal and failing heart muscle. Cardiac myosin activation triggers faster myosin crossbridge cycling with greater force generation during each contraction. We describe the rationale and results of a translational medicine effort to increase dATP levels using a gene therapy strategy that upregulates ribonucleotide reductase, the rate-limiting enzyme for dATP synthesis, selectively in cardiomyocytes. In small and large animal models of heart failure, a single dose of this gene therapy has led to sustained inotropic effects with no toxicity or safety concerns identified to-date. Further animal studies are being conducted with the goal of testing this agent in patients with heart failure.

Challenges in acute heart failure clinical management: optimizing care despite incomplete evidence and imperfect drugs.

Acute heart failure is a common condition associated with considerable morbidity, mortality, and cost. However, evidence-based data on treating heart failure in the acute setting are limited, and current individual treatment options have variable efficacy. The healthcare team must often individualize patient care in ways that may extend beyond available clinical guidelines. In this review, we address the question, "How do you do the best you can clinically with incomplete evidence and imperfect drugs?" Expert opinion is provided to supplement guideline-based recommendations and help address the typical challenges that are involved in the management of patients with acute heart failure. Specifically, we discuss 4 key areas that are important in the continuum of patient care: differential diagnosis and risk stratification; choice and implementation of initial therapy; assessment of the adequacy of therapy during hospitalization or observation; and considerations for discharge/transition of care. A case study is presented to highlight the decision-making process throughout each of these areas. Evidence is accumulating that should help guide patients and healthcare providers on a path to better quality of care.

Effect of serelaxin on cardiac, renal, and hepatic biomarkers in the Relaxin in Acute Heart Failure (RELAX-AHF) development program: correlation with outcomes.

OBJECTIVES: The aim of this study was to assess the effects of serelaxin on short-term changes in markers of organ damage and congestion and relate them to 180-day mortality in patients with acute heart failure. BACKGROUND: Hospitalization for acute heart failure is associated with high post-discharge mortality, and this may be related to organ damage. METHODS: The Pre-RELAX-AHF (Relaxin in Acute Heart Failure) phase II study and RELAX-AHF phase III study were international, multicenter, double-blind, placebo-controlled trials in which patients hospitalized for acute heart failure were randomized within 16 h to intravenous placebo or serelaxin. Each patient was followed daily to day 5 or discharge and at days 5, 14, and 60 after enrollment. Vital status was assessed through 180 days. In RELAX-AHF, laboratory evaluations were performed daily to day 5 and at day 14. Plasma levels of biomarkers were measured at baseline and days 2, 5, and 14. All-cause mortality was assessed as a safety endpoint in both studies. RESULTS: Serelaxin reduced 180-day mortality, with similar effects in the phase II and phase III studies (combined studies: N = 1,395; hazard ratio: 0.62; 95% confidence interval: 0.43 to 0.88; p = 0.0076). In RELAX-AHF, changes in markers of cardiac (high-sensitivity cardiac troponin T), renal (creatinine and cystatin-C), and hepatic (aspartate transaminase and alanine transaminase) damage and of decongestion (N-terminal pro-brain natriuretic peptide) at day 2 and worsening heart failure during admission were associated with 180-day mortality. Serelaxin administration improved these markers, consistent with the prevention of organ damage and faster decongestion. CONCLUSIONS: Early administration of serelaxin was associated with a reduction of 180-day mortality, and this occurred with fewer signs of organ damage and more rapid relief of congestion during the first days after admission.

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.

Design of the RELAXin in acute heart failure study.

BACKGROUND: Acute heart failure (AHF) remains a major public health burden with a high prevalence and poor prognosis. Relaxin is a naturally occurring peptide hormone that increases cardiac output, arterial compliance, and renal blood flow during pregnancy. The RELAX-AHF-1 study will evaluate the effect of RLX030 (recombinant form of human relaxin 2) on symptom relief and clinical outcomes in patients with AHF. METHODS: The protocol includes a completed phase 2 234-patient dose-finding study (Pre-RELAX-AHF) and an ongoing phase 3 1,160-patient trial (RELAX-AHF-1). Patients with AHF and systolic blood pressure >125 mm Hg are randomized within 16 hours of presentation to a 48-hour IV infusion of RLX030 or placebo. The 30 µg/kg per day dose of RLX030 was chosen for RELAX-AHF-1 based on effects on dyspnea, clinical outcomes, and safety observed in Pre-RELAX-AHF. Primary efficacy end points in RELAX-AHF-1 are (1) the area under the curve of change of the dyspnea Visual Analog Scale from baseline through day 5 and (2) whether the patient reports moderately to markedly better dyspnea at 6, 12, and 24 hours. Secondary efficacy end points include days alive and out of the hospital through day 60 and cardiovascular death or rehospitalization for heart failure or renal failure through day 60. Patients will be followed up through day 180 for mortality. As of September 19, 2011, 978 patients have been enrolled. CONCLUSIONS: Pre-RELAX-AHF results suggested that infusion of RLX030 may accelerate dyspnea relief and improve prognosis in patients hospitalized with AHF. RELAX-AHF-1 will further evaluate these effects.

Early drop in systolic blood pressure and worsening renal function in acute heart failure: renal results of Pre-RELAX-AHF.

AIMS: We aimed to determine the relation between baseline systolic blood pressure (SBP), change in SBP, and worsening renal function (WRF) in acute heart failure (AHF) patients enrolled in the Pre-RELAX-AHF trial. METHODS AND RESULTS: The Pre-RELAX-AHF study enrolled 234 patients within 16 h of admission (median 7 h) for AHF and randomized them to relaxin given intravenous (i.v.) for 48 h or placebo. Blood pressure was measured at baseline, at 3, 6, 9, 12, 24, 36, and 48 h and at 3, 4, and 5 days after enrolment. Worsening renal function was defined as a serum creatinine increase of ≥0.3 mg/dL by Day 5. Worsening renal function was found in 68 of the 225 evaluable patients (30%). Patients with WRF were older (73.5 ± 9.4 vs. 69.1 ± 10.6 years; P= 0.003), had a higher baseline SBP (147.3 ± 19.9 vs. 140.8 ± 16.7 mmHg; P= 0.01), and had a greater early drop in SBP (37.9 ± 16.0 vs. 31.4 ± 12.2 mmHg; P= 0.004). In a multivariable model, higher age, higher baseline creatinine, and a greater early drop in SBP, but not baseline SBP, remained independent predictors of WRF. Furthermore, WRF was associated with a higher Day 60 (P= 0.01), and Day 180 (P= 0.003) mortality. CONCLUSIONS: Worsening renal function in hospitalized AHF patients is related to a poor clinical outcome and is predicted by a greater early drop in SBP. Trial registration clinicaltrials.gov identifier NCT00520806.

Permutation criteria to evaluate multiple clinical endpoints in a proof-of-concept study: lessons from Pre-RELAX-AHF.

BACKGROUND: Clinically relevant endpoints cannot be routinely targeted with reasonable power in a small study. Hence, proof-of-concept studies are often powered to a primary surrogate endpoint. However, in acute heart failure (AHF) effects on surrogates have not translated into clinical benefit in confirmatory studies. Although observing an effect on one of many endpoints due to chance is likely, observing concurrent positive trends across several outcomes by chance is usually unlikely. METHODS: Pre-RELAX-AHF, which compared 4 relaxin doses with placebo in AHF, has shown favourable trends versus placebo (one-sided P < 0.10) on six of nine clinical endpoints in the 30 µg/kg/day group. To illustrate evaluation of multiple, correlated clinical endpoints for evidence of efficacy and for dose selection, a permutation method was applied retrospectively. By randomly re-assigning the treatment group to the actual data for each of the 229 subjects, 20,000 permutation samples were constructed. RESULTS: The permutation P value for at least six favourable trends among nine endpoints in any dose groups was 0.0073 (99.9% CI 0.0053-0.0093). This is higher than would be expected if the endpoints were uncorrelated (0.00026), but much lower than the probability of observing one of nine comparisons significant at the traditional two-sided P < 0.05 (0.74). Thus, the result was unlikely due to correlated endpoints or to chance. CONCLUSIONS: Examining consistency of effect across multiple clinical endpoints in a proof-of-concept study may identify efficacious therapies and enable dose selection for confirmatory trials. The merit of the approach described requires confirmation through prospective application in designing future studies.

Low lymphocyte ratio as a novel prognostic factor in acute heart failure: results from the Pre-RELAX-AHF study.

BACKGROUND: Previous studies have suggested that a lower lymphocyte ratio (Ly%) in the white blood cell (WBC) differential count is related to worse outcomes in patients with acute heart failure (AHF) and other cardiovascular disorders. METHODS: In the Pre-RELAX-AHF study, 234 patients with AHF, systolic blood pressure >125 mm Hg and brain natriuretic peptide ≥350 pg/ml or equivalent were randomized to 1 of 4 intravenous doses of relaxin or placebo and followed up for 6 months following randomization. Complete blood count and differential were performed by a central laboratory at baseline and then daily to day 5 and on day 14. RESULTS: The WBC count by itself was not associated with measures of disease severity or outcome, and patients with Ly% <13% had similar baseline characteristics to patients with Ly% >13%, except for a higher baseline WBC count, elevated baseline glucose, older age and higher rates of peripheral vascular disease. However, patients with Ly% <13% had less improvement of dyspnea, greater worsening of heart failure, longer length of initial hospital stay and fewer days alive and out of hospital. Statistical significance was reached for all-cause death by days 60 and 180 (hazard ratio = 1.11 per percent decrease, 95% confidence interval 1.03-1.19; p = 0.0048). CONCLUSIONS: Despite no association with any baseline characteristic known to strongly predict outcome in AHF, low Ly% is associated with less symptom relief and worse in-hospital and postdischarge clinical outcomes.

Acute heart failure clinical drug development: from planning to proof of activity to phase III.

Over the last decades, attempts to develop new therapies for acute heart failure (AHF) have largely failed. Limitations in understanding the pathophysiology of AHF, its natural history, the effects of current therapies, the properties of new agents, and, importantly, study designs and execution have contributed to these disappointing results. We propose a novel approach for the development of new agents for AHF. Initial stages of development (proof of activity and phase IIa studies) should provide a granular understanding of the mechanism of the actions and pharmacodynamic properties of the new intervention, first in animal models of HF and then in small tightly designed human studies. This will facilitate the identification of patients who are more likely to show a favorable response. In phase II studies (proof of concept), the assessment of efficacy and final dose selection should not be based on surrogate endpoints but rather on clinically meaningful endpoints such as the relief of AHF symptoms, i.e. breathlessness, as well as consistent trends in the relief of other symptoms and clinical signs of recurrence (worsening HF either in hospital or after discharge) and short-term mortality. Lastly, other safety parameters, i.e. effects such as renal and myocardial damage, should be assessed. In some instances, the decision to move to phase III may be based on clear consistent trends rather than on 1 statistically significant endpoint. In studies that confirm clinical utility (phase III), efficacy will be judged relative to the magnitude of the benefit, i.e. improvements in symptoms (breathlessness), the prevention of symptom recurrence, and short-term mortality, balanced by the consideration of safety signals including an estimation of absolute mortality.

Dyspnoea and worsening heart failure in patients with acute heart failure: results from the Pre-RELAX-AHF study.

AIMS: Although dyspnoea is the most common cause of admission for acute heart failure (AHF), more needs to be known about its clinical course and prognostic significance. METHODS AND RESULTS: The Pre-RELAX-AHF study randomized 232 subjects with AHF to placebo or four doses of relaxin and evaluated early (6-24 h Likert scale) and persistent [change in visual analogue scale area under the curve (VAS AUC) through Day 5] dyspnoea relief. Worsening heart failure (WHF) was defined as worsening AHF signs and symptoms requiring additional therapy. Patients were followed until Day 180. Early dyspnoea relief was observed in only 25% of all patients, and VAS AUC at 5 days was 45% over baseline values in all patients (32% placebo; 50% all relaxin-treated patients). Worsening heart failure to Day 5 was observed in 16% of all patients (21% placebo; 14% relaxin). Lack of persistent dyspnoea relief and WHF were associated with a longer length of initial hospital stay and worse 60-day outcomes. CONCLUSION: Dyspnoea relief in patients admitted with AHF is often incomplete, and many may show WHF after the initial stabilization. Both lack of persistent dyspnoea relief and in-hospital WHF predict a longer length of stay and worse outcome.

Relaxin: review of biology and potential role in treating heart failure.

Relaxin is a naturally occurring human peptide initially identified as a reproductive hormone. More recently, relaxin has been shown to play a key role in the maternal hemodynamic and renal adjustments that accommodate pregnancy. An understanding of these physiologic effects has led to the evaluation of relaxin as a pharmacologic agent for the treatment of patients with acute heart failure. Preliminary results have been encouraging. In addition, the other known biologic properties of relaxin, including anti-inflammatory effects, extracellular matrix remodeling effects, and angiogenic and anti-ischemic effects, all may play a role in potential benefits of relaxin therapy. Ongoing, large-scale clinical testing will provide additional insights into the potential role of relaxin in the treatment of heart failure.

Scientific rationale and design of a phase I safety study of relaxin in women with severe preeclampsia.

The pathophysiology of preeclampsia involves profound systemic vasoconstriction. Its etiology may be related to reduced blood flow to the placenta, leading to the elaboration of soluble, vasoactive factors which increase maternal systemic vascular resistance and cause renal dysfunction. Reduced bioactivity of vascular endothelial growth factor (VEGF) may play a central role in this pathophysiology. Previous clinical studies have strongly suggested that relaxin is a systemic and renal vasodilator. In nonclinical studies, relaxin administration to monkeys has been associated with increased vessel density in the endometrium, and in previous human trials relaxin administration has been highly correlated with increased menstrual bleeding in women. VEGF has been proposed as a mechanism for these endometrial effects. Together, these data suggest that relaxin may be able to relieve systemic and renal vasoconstriction and improve placental perfusion in women with preeclampsia. As a first step in the development program for relaxin in this indication, a multicenter, randomized, double-blind, placebo-controlled phase I safety study in women with severe preeclampsia has been launched in the USA. Three doses of relaxin, 3, 10, and 30 microg/kg of body weight/day, or placebo, will be administered for up to 72 h in women admitted to the hospital for management of their disease. Although the trial is primarily focused on safety, signs of efficacy, such as changes in blood pressure and renal markers, will also be assessed.

Relaxin for the treatment of patients with acute heart failure (Pre-RELAX-AHF): a multicentre, randomised, placebo-controlled, parallel-group, dose-finding phase IIb study.

BACKGROUND: Most patients admitted for acute heart failure have normal or increase blood pressure. Relaxin is a natural human peptide that affects multiple vascular control pathways, suggesting potential mechanisms of benefit for such patients. We assessed the dose response of relaxin's effect on symptom relief, other clinical outcomes, and safety. METHODS: In a placebo-controlled, parallel-group, dose-ranging study, 234 patients with acute heart failure, dyspnoea, congestion on chest radiograph, and 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 were recruited from 54 sites in eight countries and enrolled within 16 h of presentation. Patients were randomly assigned, in a double-blind manner via a telephone-based interactive voice response system, to standard care plus 48-h intravenous infusion of placebo (n=62) or relaxin 10 microg/kg (n=40), 30 microg/kg (n=43), 100 microg/kg (n=39), or 250 microg/kg (n=50) per day. Several clinical endpoints were explored to assess whether intravenous relaxin should be pursued in larger studies of acute heart failure, to identify an optimum dose, and to help to assess endpoint selection and power calculations. Analysis was by modified intention to treat. This study is registered with ClinicalTrials.gov, number NCT00520806. FINDINGS: In the modified intention-to-treat population, 61 patients were assessed in the placebo group, 40 in the relaxin 10 microg/kg per day group, 42 in the relaxin 30 microg/kg per day group, 37 in the relaxin 100 microg/kg per day group, and 49 in the relaxin 250 microg/kg per day group. Dyspnoea improved with relaxin 30 microg/kg compared with placebo, as assessed by Likert scale (17 of 42 patients [40%] moderately or markedly improved at 6 h, 12 h, and 24 h vs 14 of 61 [23%]; p=0.044) and visual analogue scale through day 14 (8214 mm x h [SD 8712] vs 4622 mm x h [9003]; p=0.053). Length of stay was 10.2 days (SD 6.1) for relaxin-treated patients versus 12.0 days (7.3) for those given placebo, and days alive out of hospital were 47.9 (10.1) versus 44.2 (14.2). Cardiovascular death or readmission due to heart or renal failure at day 60 was reduced with relaxin (2.6% [95% CI 0.4-16.8] vs 17.2% [9.6-29.6]; p=0.053). The number of serious adverse events was similar between groups. INTERPRETATION: When given to patients with acute heart failure and normal-to-increased blood pressure, relaxin was associated with favourable relief of dyspnoea and other clinical outcomes, with acceptable safety.

A preliminary assessment of the effects of ATI-2042 in subjects with paroxysmal atrial fibrillation using implanted pacemaker methodology.

AIMS: ATI-2042 (budiodarone) is a chemical analogue of amiodarone with a half life of 7 h. It is electrophysiologically similar to amiodarone, but may not have metabolic and interaction side effects. The sophisticated electrocardiograph logs of advanced DDDRP pacemakers were used to monitor the efficacy of ATI-2042. The aim of this study was to determine the preliminary efficacy and safety of ATI-2042 in patients with paroxsymal atrial fibrillation (PAF) and pacemakers. METHODS AND RESULTS: Six women with AF burden (AFB) between 1 and 50% underwent six sequential 2-week study periods. Patients received 200 mg bid of ATI-2042 during Period 2 (p2), 400 mg bid during p3, 600 mg bid during p4, 800 mg bid during p5, and no drug during baseline and washout (p1 and p6). Pacemaker data for the primary outcome measure AFB were downloaded during each period. Mean AFB decreased between baseline and all doses: AFB at baseline (SD) was 20.3 +/- 14.6% and mean AFB at 200 mg bid was 5.2 +/- 4.2%, at 400 mg bid 5.2 +/- 5.2%, at 600 mg bid 2.8 +/- 3.4%, and at 800 mg bid 1.5 +/- 0.5%. The mean reductions in AFB at all doses of ATI-2042 were statistically significant (P < 0.005). Atrial fibrillation burden increased in washout. Atrial fibrillation episodes tended to increase with ATI-2042, but this was offset by substantial decreases in episode duration. ATI-2042 was generally well tolerated. CONCLUSION: ATI-2042 effectively reduced AFB over all doses studied by reducing mean episode duration. A large-scale study will be required to confirm this effect.

Relaxin, a pleiotropic vasodilator for the treatment of heart failure.

Relaxin is a naturally occurring peptide hormone that plays a central role in the hemodynamic and renovascular adaptive changes that occur during pregnancy. Triggering similar changes could potentially be beneficial in the treatment of patients with heart failure. The effects of relaxin include the production of nitric oxide, inhibition of endothelin, inhibition of angiotensin II, production of VEGF, and production of matrix metalloproteinases. These effects lead to systemic and renal vasodilation, increased arterial compliance, and other vascular changes. The recognition of this has led to the study of relaxin for the treatment of heart failure. An initial pilot study has shown favorable hemodynamic effects in patients with heart failure, including reduction in ventricular filling pressures and increased cardiac output. The ongoing RELAX-AHF clinical program is designed to evaluate the effects of relaxin on the symptoms and outcomes in a large group of patients admitted to hospital for acute heart failure. This review will summarize both the biology of relaxin and the data supporting its potential efficacy in human heart failure.