The Immunetrics team is driven to advance mechanistic understanding of diseases, to advance global modeling capabilities, and to improve healthcare outcomes. With experts in mathematics, biology, and software engineering, we collaborate closely with our clients to solve new challenges with the most impact.


Steven Chang, M.S., CEO, Board Member, is a successful technology entrepreneur with more than 30 years of experience in identifying emerging market needs and combining state of the art technologies and resources to meet those needs. This includes raising over $30 million in corporate capital and starting/leading multiple early stage companies. His career includes diverse markets such as power generation, transportation logistics, critical care medicine, pharmaceutical drug development, quantitative systems pharmacology and mobile applications. He played a role in the early years of the monetization of the Internet by providing key research and development for multiple companies, including Yahoo!, to target users based on their specific behavior and interests. In the late 1990s, he helped commercialize proprietary technologies that enabled real-time ad hoc query processing on terabyte sized databases with no loss in data resolution.

Many of the technologies and products offered under his direction have been key to keeping billion dollar businesses competitive in their respective markets. Early in his career, Steve headed up the Intelligent Software Systems group at Westinghouse/CBS Corporation’s Science and Technology Center and developed decision optimization and computer modeling systems that were successfully deployed in many Fortune 500 companies, including Kraft Foods, Colgate-Palmolive, Nestle, and Airborne Express. He was also instrumental in establishing the first Westinghouse presence on the Internet and was the recipient of two George Westinghouse Signature Awards for Excellence. Steve attained both BS and MS degrees in Electrical Engineering from the Rensselaer Polytechnic Institute.

John Bartels, Chief Technology Officer, has been developing mathematical models for more than 20 years, primarily in biological applications. John provides the technical direction and foundation for Immunetrics’ custom simulation platforms and proprietary tools. Prior to joining Immunetrics, John held senior engineering positions at Nomos Corporation, Westinghouse Electric Corporation, and Digital Equipment Corporation. John holds a B.S. in Computer Science from the Rensselaer Polytechnic Institute and an M.S. in Mathematics from the University of Pittsburgh.

Patricia Rogan, Vice President, Operations, has more than 30 years of experience in executive financial and administrative management at public, private and startup technology companies, including software and biotechnology firms. Prior to joining Immunetrics, Pat was an executive at Innovation Works, Inc., a regional seed stage investor in technology companies. She previously held executive management positions at LaunchCyte, LLC and Dravo Corporation. Pat holds a B.A. and an MBA from the University of Pittsburgh.

John Harn, Platform Manager, Quantitative Systems Pharmacology  oversees the professional services group which develops QSP models for Immunetrics’ pharmacological clients. John has over 30 years of experience in the development of instrumentation and distributed control systems for industrial and laboratory applications. For the past 20 years, he has specialized in the development of healthcare related applications. Prior to joining Immunetrics, John managed a group that developed instrumentation and laboratory management software for a clinical laboratory that specialized in oncology. John has a B.S. in Electrical Engineering and a B.S. with majors in Computer Science and Applied Mathematics from Geneva College, and a M.S. in Electrical Engineering from the University of Pittsburgh.

Board of Directors

Tom Petzinger, Board Member, is Executive Vice President of Knopp Neurosciences Inc. and CEO of LaunchCyte LLC, a founder of Immunetrics and five other life science companies. He also serves on the boards of Reaction Biology Corp., Crystalplex Corp., and Celsense Inc. Prior to co-founding LaunchCyte, he spent 22 years at The Wall Street Journal in several capacities, including Washington Economics Editor, Deputy Washington Bureau Chief, and weekly columnist. The author of three books, Tom holds a B.S. in journalism from Northwestern University, where he was a Richter Undergraduate International Scholar.

William Macias, MD, PhD, Board Member, has over 26 years of drug development experience and currently provides consulting services as CEO of Focus Biomedical Consulting LLC.  Prior to founding Focus Biomedical Consulting, he was a Distinguished Medical Fellow and member of senior management at Eli Lilly and Company.  During his 23 years at Lilly, he held multiple roles in early, mid, and late stage drug development.  He led multiple global registration programs leading to submission and approval of medications across diverse therapeutic areas (critical care, cardiology and immunology) in both biologic and small molecules.  Prior to joining Lilly he was an Associate Professor of Medicine at the Indiana University Medical Center.  He held board certifications in Internal Medicine, Nephrology, and Critical Care Medicine.