Facility Overview

Charles River’s site in Mattawan, Michigan, performs general toxicology studies and specialized studies such as DART, ototoxicity, ocular toxicology, and abuse liability. The facility also supports the development of medical devices and gene and cell therapies.

Download Mattawan, Michigan, At-a-Glance sheet

Meet the Team

The addition of experts and scientists from MPI Research brings fresh perspectives and years of experience to our growing Safety Assessment team. Take a moment for a quick “meet and greet” with a few of our new team members.

  • Roger Hayes, PhD, Sr. Director, Laboratory Sciences

    Roger Hayes

    Roger Hayes, PhD, is Senior Director, Laboratory Sciences at Charles River. Before joining the company in 2011, Dr. Hayes has held numerous leadership positions in the global life sciences industry and academia, leading teams in the development of state-of-the-art bioanalytical and analytical techniques, including mass spectrometry, chromatography, and automation in bringing medical and chemical products to market. For nearly two decades, he has led strategic and research initiatives for large pharmaceutical companies that included both GLP and non-GLP preclinical studies and clinical trials. At Merck Research Laboratories, Dr. Hayes directed the regulated bioanalysis group in support of preclinical and clinical safety trials and also advanced efficiencies for method development and validation. At Parke-Davis Pharmaceuticals, he managed the instrumentation support department, headed the bioanalytical groups for both safety and discovery research, and performed cutting-edge work as the leader of the drug metabolism mass spectrometry group. Before 1993, Dr. Hayes spent several years at Procter and Gamble, where he developed new analytical technology and processes.

    His career is rooted in academia, beginning at the University of Adelaide in Australia, where he received his PhD in 1985 and performed innovative research in gas phase ion chemistry. From there, he went to the University of Nebraska-Lincoln, where he served as an assistant director/assistant research professor and continued his groundbreaking research, with an emphasis on advancements in the use of mass spectrometry. Most recently, he served as President of Bioanalytical Operations, at Cetero Research where he focused on establishing overall corporate direction for bioanalytical and analytical services. Dr. Hayes has published extensively and has taught numerous aspects of LC/MS method development. He is an active member of the American Society for Mass Spectrometry and the American Association of Pharmaceutical Scientists.

  • Theodore Baird, PhD, DSP, Sr. Director of Safety Evaluation & Principal Study Director

    Theodore Baird

    Theodore Baird, PhD, DSP, serves as Senior Director of Safety Evaluation, and as a Principal Study Director at Charles River. He is also an adjunct professor in the Biomedical Sciences Department at Western Michigan University. Dr. Baird received his PhD in biological psychology from the University of Oklahoma Health Sciences Center in 1998, and came to MPI Research following a postdoctoral research fellowship in the Department of Pharmacology at the University of Michigan.  As an expert with 18 years of pharmaceutical industry experience, Dr. Baird has authored more than 450 reports on proprietary compounds with respect to cardiovascular, renal, gastrointestinal, central nervous and respiratory system safety and/or efficacy, as well as conducting a wide range of regulatory general toxicology studies in mice, rats, rabbits, guinea pigs, dogs, swine, and nonhuman primates. Dr. Baird’s publication record includes over 165 presentations, abstracts, and/or manuscripts. He is presently a member of the American College of Toxicology, as well as a current member and Diplomate of the Safety Pharmacology Society.

  • Dan Patrick DVM, DACVP, DABT, Toxicologic Pathologist & Director of Pathology

    Dan Patrick headshot

    Dan Patrick DVM, DACVP, DABT is a toxicologic pathologist and the Director of Pathology at Charles River. He received his DVM from Iowa State University, completed anatomic pathology residency training at Michigan State University, and is board certified by the American College of Veterinary Pathologists (ACVP) and the American Board of Toxicology (ABT). He has broad experience with the safety assessment of a wide variety of laboratory animal species and study types and promotes integration between pathologists, cross functional areas, external scientists, and Sponsors; providing problem-solving and mediation as needed. He has authored many scientific articles and textbook chapters and enjoys educational outreach, serving as an adjunct professor in the College of Veterinary Medicine at Michigan State University and serving as coordinator for the toxicologic pathology residency program at Michigan State University. Currently he is serving as an ACT Councilor and member the Society of Toxicologic Pathology’s (STP) Scientific and Regulatory Policy Committee which provides focus and perspective on scientific and regulatory issues which are pivotal to the practice of toxicologic pathology. Other ACT activities include serving as a liaison between the ACT and STP, organizer for ACT “Pathology for Non-Pathologists” courses, and has presented at ACT Annual Meetings and webinars. He is a member of the STP, ACT, SOT, ACVP, European Society of Toxicologic Pathology, and the American Veterinary Medical Association.

  • Mark Johnson, MS, Sr. Director of Surgical & Ophthalmology Services

    Mark Johnson

    Mark Johnson, MS, is the Senior Director of Surgical & Ophthalmology Services at Charles River. As an expert with more than 15 years of experience, he provides leadership for business development, scientific advancements, and oversight of the high-quality performance of the surgical staff, while performing GLP and non-GLP medical device evaluation, safety pharmacology, efficacy, as well as acute and sub chronic general toxicology studies in multiple species and surgical models. His areas of expertise include development of gene and cellular therapeutics for treatment of neurodegenerative and cardiovascular diseases, drug eluting coronary stents and other types of combination products, and development of small and large molecules requiring unique routes of administration to enhance the therapeutic benefit of the compound. Before joining MPI Research in 2000 as an Associate Study Director, he was a research associate in pharmacology and neuroscience at the University of Michigan. Mr. Johnson received his MS in neuropsychology from Eastern Michigan University in 1997. Mr. Johnson has presented and published extensively in the field of safety and efficacy studies with various biologic, pharmaceutical and medical devices. He is an active member of the Society for Biomaterials and the American Society of Gene and Cell Therapy.

  • Thomas Vihtelic, DVM, PhD, Director & Sr. Study Director of Experimental Therapeutics

    Thomas Vihtelic

    Thomas Vihtelic, DVM, PhD joined MPI Research in 2008 as a Study Director in Targeted Discovery Research and now serves as Director and Senior Study Director of Experimental Therapeutics. Dr. Vihtelic assists Sponsors in the design of preclinical studies in support of ophthalmology, inflammation, parasitology, and infectious disease therapies. Before joining MPI Research, he was a Research Associate Professor of Biology at the University of Notre Dame using molecular genetic strategies to study eye lens development and establishing a model of light-induced photoreceptor degeneration to characterize adult stem cell roles in the regenerating zebrafish retina. Dr. Vihtelic received a DVM from Michigan State University and a doctorate in molecular genetics from the University of Notre Dame. His doctoral research, which focused on characterization of Drosophila retinal degeneration genes, was followed by postdoctoral work at the University of Chicago (Department of Ophthalmology and Visual Sciences) and the Massachusetts Eye and Ear Infirmary (Howe Laboratory of Retina Molecular Genetics and Harvard Medical School) using mouse retinal degeneration mutants and transgenic lines. Dr. Vihtelic has presented and published in the field of experimental ophthalmology and maintains memberships in the Association for Research in Vision and Ophthalmology and American Association of Veterinary Parasitologists.

  • Rachel Tapp, MS, LATG, Sr. Study Director of Neurobehavioral Sciences

    Rachel Tapp

    Rachel Tapp, MS, LATG, is a Senior Study Director in neurobehavioral sciences at Charles River. As an expert with more than 15 years of experience, she ensures high level performance of regulatory and non-regulatory contracted neurobehavioral ototoxicity studies, focusing on study management, communication, and fostering Sponsor relationships. Ms. Tapp joined MPI Research in 2003 as a research associate and was promoted to Study Director in 2005. Before joining the company, she worked as a field research technician at the National Audubon Society and as a laboratory assistant in the Aquatic Toxicology Laboratory at Michigan State University. Ms. Tapp obtained her BS in zoology from Michigan State University in Michigan in 2002, and her MS in Pharmacology and Toxicology from Michigan State University in 2016. She has authored many auditory safety posters and articles and is an active member of the Association for Research in Otolaryngology, the Society for Neuroscience, and the Safety Pharmacology Society.

  • Joshua Bartoe, MS, DVM, Director of Ophthalmology Services

    Joshua Bartoe

    Joshua Bartoe, MS, DVM, serves as the Director of Ophthalmology Services at Charles River. He also remains an adjunct associate professor in the College of Veterinary Medicine at Michigan State University. Dr. Bartoe joined MPI Research full-time in 2014 after an 11 career in academic veterinary ophthalmology.  Previously he provided consulting services to MPI Research for 8 years. He graduated from The Ohio State University with his Doctorate in Veterinary Medicine in 2001 and was board-certified as a Diplomate of the American College of Veterinary Ophthalmologists in 2006 following residency training at Kansas State University. He brings a deep history of ophthalmology experience and study expertise to MPI Research. Dr. Bartoe is an active member of the Association for Research in Vision and Ophthalmology, Society of Toxicology, SOT Ocular Toxicology Specialty Section, as well as the American College of Veterinary Ophthalmologists.