The Authors

Dennis P Heller, Ph.D.

Dr. Heller is Vice President of Drug Development for XenoBiotic Laboratories (XBL) Inc. In his current role, Dr. Heller is responsible for Business Development, Marketing, Client management, and Project management support. On the scientific side, Dr. Heller has been involved with human radiolabel DMPK and biodistribution imaging studies, dosimetry and PK analysis for over 15 years.

Prior to joining XBL in 2004, Dr. Heller was VP, Business Development for Pharmaceutical Profiles, a UK CRO that utilized gamma scintigraphy in drug development. From 1996-2000, Dr. Heller was Associate Director of Imaging and Radiopharmaceuticals for MDS Pharma Services (formerly Phoenix International Life Sciences) where he conducted many human radiolabel mass balance studies. Prior to moving to industry, Dr. Heller was Assistant Professor, Department of Radiology, Division of Radiation Oncology at the University of Cincinnati, Ohio where he taught graduate courses in radiation biology conducted research into the mechanisms of radiation resistance of cancer cells.

Dr. Heller received his B.Sc. in Physics from the University of Waterloo, M.Sc. in Medical Physics from the University of Manitoba, and Ph.D. in Medical Physics/Radiation Biology from Carleton University all in Canada.

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Ronald E. White, Ph.D.

Ronald E. White, Ph.D. is President of White Global Pharma Consultants, LLC, based in Cranbury, New Jersey. He was formerly Senior Vice President for DMPK Science and Technology at XenoBiotic Laboratories, Inc., Distinguished Research Fellow, Pharmaceutical Candidate Optimization at Bristol-Myers Squibb, and Vice President of Drug Metabolism and Pharmacokinetics at the Schering-Plough Research Institute.

Prior to joining industry in 1987, he was Associate Professor of Pharmacology at the University of Connecticut School of Medicine. He is presently a member of the Editorial Board of the journal Drug Metabolism and Disposition and Adjunct Professor of Chemical Biology in the Rutgers University School of Pharmacy. Dr. White holds a Ph.D. in Organic Chemistry from the University of Wisconsin and pursued post-doctoral research in the mechanism of cytochrome P450 enzymes at the University of Michigan. He is a member of several scientific societies, including the American Chemical Society, the American Association of Pharmaceutical Sciences, the American Society for Biochemistry and Molecular Biology, and the International Society for the Study of Xenobiotics.

Dr. White has lectured and published extensively in the areas of drug metabolizing enzymes, pharmacokinetics and drug discovery and is the holder of five United States patents.

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Robert J. Guttendorf, R.Ph, Ph.D.

Dr. Guttendorf is a Senior Consultant, DMPK, at Aclairo Pharmaceutical Development Group, Inc. in Vienna, VA.  In over 25 years of pharmaceutical industry experience, he has held leadership positions in small biotech and large pharmaceutical companies, including Director of Discovery and Preclinical Development at Pfizer Global R&D and Parke-Davis Pharmaceutical Research, Scientific Strategy Advisor at Pfizer, Vice President of Pharmacology and Biopharmaceutics at Advancis (Middlebrook) Pharmaceutical Co., and Vice President of Pharmacology and Experimental Therapeutics at Sequoia Pharmaceuticals.

Prior to joining the pharmaceutical industry, Dr. Guttendorf received a B.S. in Pharmacy from West Virginia University and a Ph.D. in Pharmaceutical Sciences from the University of Kentucky. He has directed ADME/PK support for discovery through NDA across a variety of therapeutic areas, overseeing numerous nonclinical pharm-tox and clinical pharmacology programs, and a host of regulatory submissions. At Parke‑Davis/Pfizer, he helped pioneer the implementation of higher throughput ADME/PK screening approaches in drug discovery and was instrumental in defining best practices for DMPK in drug discovery and development.

He has presented and published numerous papers on various topics in ADME/PK, including the strategic use of ADME data to improve drug discovery and development.  Dr. Guttendorf holds adjunct faculty appointments at the University of Maryland University College, Hood College, and Duquesne University.

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