Senior Management
Robert F. Johnston, President & Chief Executive Officer
Mr. Johnston is CEO of ExSAR (2002–2005; 2009–present) and has been Chairman of the Board of Directors since 2002. He runs Johnston Associates, a venture capital firm that he founded in 1968 to provide seed capital for start-ups emerging in the biotechnology and healthcare fields. Mr. Johnston is the executive chairman of Pharmos Corporation, which acquired Vela Pharmaceuticals, Inc. He has founded numerous public companies including Sepracor, Cytogen (sold to EUSA Pharma), I-STAT (sold to Abbott), Genex and Envirogen (sold to Shaw Environmental), and was instrumental in the early formation of many private companies such as Sonomed, Immunicon (sold to J&J), PharmaStem (formerly Biocyte), Praelux (sold to Amersham/GE) and Targent (sold to Spectrum Pharmaceuticals). Mr. Johnston served as CEO of Cytogen from July 1988 to April 1989 and as CEO of Praelux (formerly SEQ) from November 1997 to January 1999. Additionally, he is a member of the Advisory Council of the Department of Molecular Biology at Princeton University, and the Executive Committee of the Friends of the Institute for Advanced Study in Princeton, New Jersey. Mr. Johnston received his BA from Princeton University and his MBA from New York University.
Robert J. Towarnicki, Interim President & Chief Operating Officer
Mr. Towarnicki is the President, Chief Operating Officer and a Director of ExSAR. Mr. Towarnicki’s prior experience includes serving as: President and Chief Executive Officer of Nucleonics, Inc., an RNAi therapeutics company; Chairman, President and Chief Executive Officer of Cell Pathways, Inc. (NASDAQ:CLPA), a small molecule cancer prevention and therapeutics company; and President and Chief Operating Officer of Integra LifeSciences Corporation (NASDAQ:IART), a medical device company focused on tissue regeneration technologies. Earlier experience includes: General Manager of Focus Technologies, a privately held esoteric disease reference laboratory; Vice President of Development and Operations for Collagen Corporation (NASDAQ:CGEN); Plant Manager for Pfizer Pharmaceuticals and ten years of increasing management responsibility in parenteral operations for Merck & Co. Mr. Towarnicki earned a BS and MS in Biology from Villanova University.
Yoshitomo Hamuro, PhD, Senior Director of Technology Development
Dr. Hamuro joined ExSAR in 2002 and has led the development of hydrogen/deuterium exchange (H/D-Exchange) analysis of protein dynamics, protein-ligand interactions and protein-protein interactions using mass spectrometry.
Prior to joining ExSAR, he was instrumental in the development of modern H/D-Exchange technology at the University of California, San Diego, in the laboratory of Professor Virgil Woods, scientific co-founder of ExSAR.
Dr. Hamuro previously conducted postdoctoral research on combinatorial chemistry and solid-phase chemistry at DuPont Central Research and Development and later on antibacterial β-peptides at the University of Pennsylvania in the laboratories of Professor William DeGrado. He obtained his PhD in 1996 from the University of Pittsburgh under Professor Andrew Hamilton on protein structure mimetics.
Stephen J. Coales, Manager of Technology Development & Operations
Stephen Coales has been with ExSAR since the lab was opened in 2002. Along with Yoshi Hamuro, Mr. Coales has worked on ExSAR’s H/D-Exchange Technology Service since then and has been responsible for training all lab operators in the use of ExSAR’s proprietary H/D-Exchange Systems. He has been responsible for the design, development and implementation of all of ExSAR’s custom temperature control devices, proprietary trap and proteolytic columns, fluidics systems, MS interfaces, methods and applications. Through this work, ExSAR has established protocols that allow the application of experimental times as low as 15 milliseconds. In addition to developing and maintaining the physical structure of ExSAR’s systems, Mr. Coales has also been responsible for writing methods for all of the sample handling and LC separations methods, which has included implementation of a complete range of troubleshooting documentation.
Mr. Coales came to ExSAR having worked in small molecule drug discovery at Tandem Labs, performing bioanalytical sample analysis and instrument validations. He has also worked at Bellingham & Stanley Ltd., on the development of optical refractomers and polarimeters. Prior to this he was a volunteer science teacher in West Africa for Voluntary Service Overseas, a UK charitable group. He has a bachelor’s degree in Environmental Biology from the University of Greenwich, London.