Efficacy and Safety of Ularitide for the Treatment of Acute Decompensated Heart Failure

Inclusion Criteria: 1. Males and females aged 18 to 85 years. 2. Unplanned hospitalization or emergency department visit for ADHF. Acute HF is defined as including all of the following: * Dyspnea at rest in a recumbent sitting position (30 to 45 degrees), which has worsened within the past week; * Radiological evidence of HF on a chest X-ray (if an appropriate chest; * computerized tomography scan is done; the X-ray need not be performed); * Brain natriuretic peptide (BNP) \>500 pg/mL or NT-pro BNP \>2000 pg/mL. 3. Ability to start infusion of the study drug within 12 h after initial clinical assessment. 4. Ability to reliably carry out self-assessment of symptoms. 5. Systolic blood pressure ≥116 mmHg and ≤180 mmHg at the time of randomization. 6. Persisting dyspnea at rest despite standard background therapy for ADHF (as determined by the Investigator) which must include IV furosemide (or equivalent diuretic) at ≥40 mg (or its equivalent) at any time after start of emergency services (ambulance, emergency department, or hospital). At the time of randomization, the patient must still be symptomatic. In addition, the patient should not have received an IV bolus of a diuretic for at least 2 h prior to randomization, and the infusion rates of all ongoing IV infusions of medications to treat HF must not have been increased or decreased for at least 2 h prior to randomization. 7. Ability to understand the purpose and risks of the study and provide signed and dated informed consent and authorization to use protected health information (in accordance with national and local privacy regulations). Exclusion Criteria: 1. Known active myocarditis, obstructive hypertrophic cardiomyopathy, congenital heart disease, restrictive cardiomyopathy, constrictive pericarditis, uncorrected clinically significant primary valvular disease. 2. Treatment with dobutamine at a dose \>5 μg/kg/min or use of drugs for support of BP at the time of randomization. 3. Treatment with levosimendan, milrinone, or any other phosphodiesterase inhibitor within 7 days before randomization. 4. Treatment with nesiritide within 30 days before randomization. 5. Creatinine clearance \<25 mL/min/1.73m² (as measured by the MDRD formula) at the time of screening. 6. Planned coronary revascularization procedure (percutaneous coronary intervention or coronary artery bypass grafting) within 5 days of randomization. 7. Clinical diagnosis of acute coronary syndrome meeting any 2 of the following 3 criteria: 1. Prolonged chest pain at rest, or an accelerated pattern of angina 2. Electrocardiogram changes indicative of ischemia or myocardial injury defined as: a new ST elevation at the J point of two anatomically contiguous leads with the cut-off points: ≥0.2 mV in men ≥40 years (\>0.25 mV in men \<40 years) or ≥0.15 mV in women in leads V2-V3 and/or ≥0.1 mV in other leads; or ST depression and T wave changes. New horizontal or down sloping ST depression ≥0.05 mV in two contiguous leads; and/or new T inversion ≥0.3 mV in two contiguous leads. 3. Serum troponin \>3 times upper limit of normal. 8. Clinically suspected acute mechanical cause of ADHF (e.g., papillary muscular rupture). The diagnosis need not be confirmed by imaging or cardiac catheterization. 9. Anemia (hemoglobin \<9 g/dL or a hematocrit \<25%). 10. Known vasculitis, active infective endocarditis, or suspected infections, e.g., pneumonia, acute hepatitis, systemic inflammatory response syndrome, or sepsis. 11. Body temperature ≥38°C just prior to randomization. 12. Acute or chronic respiratory disorder (e.g., severe chronic obstructive pulmonary disease) or primary pulmonary hypertension sufficient to cause dyspnea at rest, which may interfere with the ability to interpret dyspnea assessments or hemodynamic measurements. 13. Terminal illness other than congestive HF with expected survival \<180 days. 14. Any previous exposure to ularitide. 15. Known allergy to natriuretic peptides. 16. Participation in an investigational clinical drug study within 30 days prior to randomization. 17. Current drug abuse or chronic alcoholism sufficient to impair participation and compliance to the study protocol. 18. Women who are breast-feeding. 19. Women of child-bearing potential (i.e., pre-menopausal women) without documentation of a negative urine/blood pregnancy assay within 12 h prior to randomization. 20. Any condition that, in the Investigator's opinion, makes the patient unsuitable for study participation. 21. Legal incapacity or limited legal capacity. 22. Patients requiring mechanical circulatory support. 23. Patients with severe hepatic impairment.