The primary objective of the study is to assess the safety and tolerability of IV administration of CD-NP and the dose relationship of CD-NP on improvement of clinical symptoms and renal function in ADHF patients.

Key Inclusion Criteria:

1. Hospitalized for acute decompensated heart failure.
2. Systolic blood pressure ≥ 115 mmHg and ≤ 200 mmHg, and diastolic blood pressure ≥ 60 mmHg and ≤ 110 mmHg at screening
3. Renally compromised.
4. Female patients must be post-menopausal or surgically sterile.

Key Exclusion Criteria:

1. Acute or suspected acute myocardial infarction (AMI) or troponin levels > 3X the upper limit of normal at the institution's local laboratory
2. Cardiogenic shock
3. Evidence of uncorrected volume or sodium depletion other clinical condition that would predispose the patient to adverse events
4. Clinically significant aortic or mitral valve stenosis
5. Temperature >38°C (oral or equivalent), sepsis or active infection requiring IV anti-microbial treatment
6. ADHF due to significant arrhythmias
7. Severe renal failure defined as creatinine clearance < 30 mL/min
8. Current or planned ultrafiltration, hemofiltration, or dialysis
9. Significant pulmonary disease
10. Major neurologic event, including cerebrovascular events in the prior 60 days.
11. Acute myocarditis or hypertrophic obstructive, restrictive, or constrictive cardiomyopathy (not including restrictive mitral filling patterns)
12. Known hypersensitivity or allergy to natriuretic peptide or its components, nesiritide, other natriuretic peptides or related compounds