Calcilytic compounds are small molecule antagonists of the calcium receptor that temporarily increase the secretion of the body's own parathyroid hormone, which may result in the formation of new bone. Under the terms of an August 2011 agreement, GSK has worldwide rights to pursue the research and the development of Ronacaleret (751689) for stem cell transplants, in addition to osteoporosis and other bone disorders. GSK will be responsible for all development, manufacturing and commercialization of Ronacaleret. NPS will be entitled to development and milestones and royalties on any future sales of Ronacaleret.