Ularitide is a recombinant form of urodilatin, a natriuretic peptide synthesized in the distal tubular cells of the kidney. It regulates renal sodium and water excretion through binding to natriuretic peptide type A receptors, increasing intracellular cyclic guanosine monophosphate (cGMP) levels. While these effects, as well as others such as vasodilation, are also exhibited by other natriuretic peptides, urodilatin has a terminal extension that brings resistance to biological inactivation by neutral endopeptidase, whose activity is increased in decompensated heart failure. Animal studies have demonstrated enhanced diuresis and natriuresis and reduced PCWP (pulmonary capillary wedge pressure) and systemic vascular resistance relative to atrial natriuretic peptide (ANP [99-126], the active circulating isoform). When injected into the blood, ularitide appears to cause diuresis (urine output) and natriuresis (sodium excretion), as well as vasodilation. Ularitide is currently in Phase 3 development as a potential treatment for patients with acute decompensated heart failure (ADHF).