Mr. Essner serves as the Board's Lead Independent Director. He previously served as Chairman, Chief Executive Officer and President of Wyeth Pharmaceuticals, Inc., a global pharmaceuticals company, which is now part of Pfizer Inc. Specifically, he served as Wyeth s Chairman between 2003 and his retirement from Wyeth in 2008, as its Chief Executive Officer between 2001 and 2007, its President between 2000 and 2006, its Chief Operating Officer between 2000 and 2001 and its Executive Vice President between 1997 and 2000. Prior to Wyeth, Mr. Essner spent more than a decade in various senior management positions at Sandoz Pharmaceuticals Corporation, in addition to serving as a Senior Advisor of Global Healthcare for The Carlyle Group Inc., a private equity, alternative asset management and financial services corporation, between 2009 and 2019. He also serves as an Executive in Residence and Adjunct Professor of Business at Columbia Business School, where he teaches courses in healthcare management, and previously served as a director of Amicus Therapeutics Inc. Mr. Essner is a graduate of Miami University and received his master s degree from the University of Chicago. Mr. Essner brings to the Board extensive industry leadership experience in the pharmaceutical industry.