Versartis, Inc. is an endocrine-focused biopharmaceutical company. It develops long-acting therapeutic proteins for the treatment of endocrine disorders. The company develops new therapeutic proteins utilizing the novel half-life extension technology XTEN. Versartis was founded by Jeffrey L. Cleland, Mark de Boer, Willem Stemmer, Volker Schellenberger, and Joshua Silverman on December 10, 2008 and is headquartered in Redwood City, CA.