NPS-2143 is an antagonist at Ca2+-sensing receptors. It displays anti-osteoporotic, neuroprotective, cardioprotective, and antihypertensive activities. This calcilytic increases bone turnover without decreasing bone mineral density. NPS-2143 also inhibits production of amyloid-β (Aβ) and VEGF and neuronal death in models of Alzheimer’s disease. This compound prevents development of pulmonary arterial hypertension (PAH) and right ventricular hypertrophy in vivo. Additionally, NPS-2143 decreases secretion of CCK, inhibits increases in intracellular Ca2+ levels, and increases secretion of parathyroid hormone (PTH).