OncoMed Pharmaceuticals, Inc. announced that its Chairman and Chief Executive Officer, Paul J. Hastings, has begun a personal leave of absence for medical reasons. Mr. Hastings will continue to be the Chief Executive Officer and Chairman of the Board of Directors during his leave of absence. In Mr. Hastings’ absence, OncoMed will be led by the Company’s senior management team including the creation of an Office of the President consisting of Executive Vice President, Research and Development, John Lewicki, and Executive Vice President and Chief Financial Officer, Sunil Patel. In addition, OncoMed’s Board of Directors has appointed a special committee of the Board, consisting of Jack Lasersohn, lead director of the Board, Perry Karsen, Deepa Pakianathan and Rick Winningham, to work closely with Dr. Lewicki and Mr. Patel during Mr. Hastings’ medical leave.