What is "paricalcitol"

Paricalcitol (chemically it is 19-nor-1,25-(OH)-vitamin D. Marketed by Abbott Laboratories under the trade name Zemplar) is a drug used for the prevention and treatment of secondary hyperparathyroidism (excessive secretion of parathyroid hormone) associated with chronic renal failure. It is an analog of 1,25-dihydroxyergocalciferol, the active form of vitamin D (ergocalciferol).