Nesiritide (hBNP): a new class of therapeutic peptide for the treatment of decompensated congestive heart failure

Agonist antibody to guanylate cyclase receptor NPR1 regulates vascular tone

Heart failure is a leading cause of morbidity and mortality1,2. Elevated intracardiac pressures and myocyte stretch in heart failure trigger the release of counter-regulatory natriuretic peptides, which act through their receptor (NPR1) to affect vasodilation, diuresis and natriuresis, lowering venous pressures and relieving venous congestion3-8. Recombinant natriuretic peptide infusions were developed to treat heart failure but have been limited by a short duration of effect9,10. Here we report that in a human genetic analysis of over 700,000 individuals, lifelong exposure to coding variants of the NPR1 gene is associated with changes in blood pressure and risk of heart failure. We describe the development of REGN5381, an investigational monoclonal agonist antibody that targets the membrane-bound guanylate cyclase receptor NPR1. REGN5381, an allosteric agonist of NPR1, induces an active-like receptor conformation that results in haemodynamic effects preferentially on venous vasculature, including reductions in systolic blood pressure and venous pressure in animal models. In healthy human volunteers, REGN5381 produced the expected haemodynamic effects, reflecting reductions in venous pressures, without obvious changes in diuresis and natriuresis. These data support the development of REGN5381 for long-lasting and selective lowering of venous pressures that drive symptomatology in patients with heart failure.

Management of diuretic-refractory, volume-overloaded patients with acutely decompensated heart failure

Fluid overload is a common presentation for decompensated heart failure, yet management strategies are poorly defined because of relatively few randomized clinical trials that delineate an optimal strategy. Patients refractory to diuretic therapy may be considered for treatment with inotropes or vasodilators, and others may be considered for venovenous ultrafiltration. The rationale for use of each therapy is reviewed.

Comparative costs of home positive inotropic infusion versus in-hospital care in patients awaiting cardiac transplantation

BACKGROUND

Outpatient positive inotropic support combined with implantation of an automatic implantable cardioverter defibrillator (AICD) may be used as a successful bridge to cardiac transplantation in patients with end-stage heart failure. A detailed comparative cost analysis of this outpatient strategy versus in-hospital care has not been previously reported.

METHODS AND RESULTS

Twenty-one United Network for Organ Sharing 1B patients awaiting cardiac transplantation received continuous outpatient inotropic therapy for a total of 3070 patient-days. Daily costs for outpatient and in-hospital treatment were calculated. Nonparametric decision analysis was used to determine the strategy with greatest cost savings (immediate hospital discharge after AICD implantation versus in-hospital care). A threshold analysis was performed to test the robustness of the decision analysis model. The outpatient strategy realized an average savings of $71,300 to $120,500 per patient. Decision analysis showed that no fixed period of in-hospital monitoring was more cost-saving than immediate hospital discharge after AICD implantation. Threshold analysis revealed that AICD costs would need to exceed $82,000 (currently $62,000) or that the difference between the outpatient and the in-hospital costs would need to be < or = $475 per day for any other intermediate strategy to be considered cost-saving.

CONCLUSION

Outpatient inotropic therapy combined with AICD implantation in selected patients awaiting cardiac transplantation is an effective cost-minimizing strategy.