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Mr. Macdonald joined the board in November 2014 and became Chairman in June 2015. Mr. Macdonald served as the President and Chief Executive Officer and member of the board of directors of Tetraphase Pharmaceuticals, Inc. (Nasdaq: TTPH) from January 2008 to August 2019. From August 2003 until January 2008, Mr. Macdonald served as Executive Vice President of Operations of Idenix Pharmaceuticals, Inc. (Nasdaq: IDIX), a biopharmaceutical company. From 1981 to 2003 he served in various positions at Merck & Co., Inc. (NYSE: MRK), most recently serving as the Vice President for Anti-Infective and Hospital Products. Mr. Macdonald received an Honors Degree in biochemistry from Dundee University in Dundee, Scotland.