Our Leadership

Robert J. Mulroy serves as our President and Chief Executive Officer and a member of our board of directors. Prior to joining Merrimack, Mr. Mulroy worked as a management consultant specializing in the healthcare and pharmaceutical industries. Mr. Mulroy also worked as a consultant in the field of international development and has served as an advisor to start-up companies in the biotechnology industry. Mr. Mulroy holds a master’s degree in public and private management from Yale University and a B.A. from Stanford University.

William A. Sullivan has served as our Chief Financial Officer since May 2011 and our Treasurer since February 2010. Mr. Sullivan served as our Controller from November 2007 to February 2010 and our Vice President of Finance from February 2010 to May 2011. Previously, Mr. Sullivan served as Corporate Controller of Vette Corp., a thermal management solutions company, from October 2004 to November 2007. Mr. Sullivan began his career at Arthur Andersen LLP, where he obtained his certified public accountant license. Mr. Sullivan holds an M.B.A. and an M.S. in accounting from Northeastern University’s Graduate School of Professional Accounting and a B.A. from Williams College. 

Fazal R. Khan, Ph.D. has led our Manufacturing division since April 2006. Prior to joining us, Dr. Khan served as Vice President of Manufacturing for Cellective Therapeutics, Inc., Vice President of Manufacturing Operations at Human Genome Sciences and Director of Biopharmaceuticals Development and Manufacturing at Hoffmann-LaRoche, Inc. Dr. Khan holds a Ph.D. and an M.S. in biochemistry and a B.S. from Aligarh University in India. 

Peter Laivins joined Merrimack in October 2011 and leads Late-stage Clinical Development. Additionally, he is Project Leader for MM-398 (nanotherapeutic-liposomal irinotecan), in Phase 3 development for Advanced Pancreatic Cancer. Prior to joining Merrimack, Mr. Laivins ran an independent consulting practice specializing in Oncology and Neuroscience. Mr. Laivins has also served as Vice President of Strategic Brand Management for ELAN BioPharmaceuticals. Mr. Laivins began his career at Pfizer Canada, Inc. and held positions of ascending responsibility at Pfizer International, in New York, and culminating as Group Leader of Pfizer US Oncology Marketing. Mr. Laivins holds an M.B.A. and a B.S. in Microbiology and Immunology from McGill University in Montreal, Canada.

Gavin MacBeath, Ph.D. is a founder of Merrimack and leads the development of predictive diagnostics focusing on identifying patients most likely to benefit from targeted therapies. Currently, he also serves on the Scientific Advisory Board of Aushon Biosciences and is a Lecturer and Principle Investigator at Harvard Medical School. He joined Merrimack in 2009 after serving on the faculty in the Department of Chemistry and Chemical Biology at Harvard University for eight years, where he focused on developing and applying protein microarray technology to facilitate basic research in the area of systems biology. Dr. MacBeath holds a Bachelors of Science from University of Manitoba, Canada, and a Ph.D. in Macromolecular and Cellular Structure and Chemistry from The Scripps Research Institute in La Jolla, California.

William M. McClements has led our Corporate Operations team since September 2011. Previously, Mr. McClements served as a member of the executive team for Integreon Managed Solutions, Inc., a global research and business services company, from May 2010 to September 2011. Before then, Mr. McClements served as Chief Operating Officer and a partner at Monitor Group, a global strategic advisory firm, from 1987 to May 2010. From September 2009 to March 2010, Mr. McClements also served as Acting President of Be the Change Inc., a non-profit focused on creating national issue-based campaigns. Mr. McClements holds an M.B.A. from Harvard Business School and a B.A. from Williams College.

Ulrik B. Nielsen, Ph.D. is a founder of Merrimack and leads the Discovery division which focuses on development of therapeutic and diagnostic programs from early stage discovery through clinical proof of concept. He also serves on the Board of Directors of Silver Creek Pharmaceuticals. Prior to joining Merrimack, Dr. Nielsen trained at University of California, San Francisco, and The Massachusetts Institute of Technology, where he researched the interface among biology, engineering and computational biology. Dr. Nielsen holds a Ph.D. in molecular biology and an M.S. in biochemistry from the University of Copenhagen, Denmark.

Birgit Schoeberl, Ph.D. is an internationally recognized leader in the application of Systems Biology to biology and drug development. At Merrimack, she leads early stage drug discovery and development programs. Currently, she also serves on the Board of Directors and Scientific Advisory Board of Silver Creek Pharmaceuticals. She joined Merrimack Pharmaceuticals in 2003 after doing postdoctoral training at MIT where she built some of the earliest computational models of signaling networks. Dr. Schoeberl holds an M.S. in chemical engineering from the University of Karlsruhe, Germany, and a Ph.D. from the Max-Planck-Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.

Edward J. Stewart leads Merrimack's commercial division which is responsible for enabling the rapid adoption of Merrimack’s novel integrated medicines by the global healthcare community.  Mr. Stewart has been with Merrimack since 2001 serving in various capacities, including most recently as Senior Vice President, Business Development. Mr. Stewart began his career at KPMG Peat Marwick LLP in the life sciences strategy consulting group. Mr. Stewart holds an M.B.A. from the Johnson Graduate School of Management at Cornell University and a B.S. from Bates College.