Clinical Staff

Mark Leibowitz, M.D., Chief Medical Officer

Mark Leibowitz, M.D. is an experienced and skilled Investigator with approximately 25 years of research experience. Dr. Leibowitz has participated in an estimated 500 studies from Phase I-IV across a variety of different indications.

As part of his research portfolio, Dr. Leibowitz has conducted highly complex studies in healthy subjects and diverse patient populations including continuous cerebrospinal fluid studies, First in Human, Single and Multiple Ascending Dose studies, Ethnic bridging programs, QTc studies, as well as, serving as Principal Investigator for many adaptive trial designs. His experience includes leadership roles such as Medical Director for research sites located in California and Texas. In addition, he is currently a contributing member for a Data Safety Monitoring Board.

Juan Pablo Frias, M.D., Medical Director

Dr. Frias, a native of Chile, completed his undergraduate studies at the University of Florida and received his medical degree from Vanderbilt University School of Medicine. After serving 5 years as a General Medical Officer in the US Navy, he completed his training in Internal Medicine at Vanderbilt University and the University of Tennessee, and his Fellowship in Endocrinology, Diabetes and Metabolism at the University of California, San Diego. Dr. Frías has held leadership positions in Clinical and Medical Affairs at Eli Lilly, Amylin Pharmaceuticals, Pfizer, and Johnson and Johnson, where he served as Chief Medical Officer and Global Vice President of Clinical and Medical Affairs, Diabetes Care. Dr. Frías has held academic positions at the University of Colorado Health Sciences Center, Barbara Davis Center for Diabetes, and the University of California San Diego School of Medicine, where he is currently on the clinical faculty. He is also active in the non-profit organization Taking Control of Your Diabetes (TCOYD), where he lectures at the organization’s Latino Initiative patient conferences and provides continuing medical education for healthcare providers. Dr. Frías has been involved in diabetes and metabolism-related research for over 15 years and has authored numerous publications in this field.

Stanley Hsia, M.D., Primary Principal Investigator

Dr. Hsia is an Associate Professor of Medicine at Charles R. Drew University of Medicine and Science, and a Health Sciences Associate Clinical Professor with the David Geffen School of Medicine at UCLA. He is board certified in Internal Medicine and

Endocrinology & Metabolism, and is a consultant endocrinologist for the Diabetes Clinic at the Martin Luther King Jr. Multi-Service Ambulatory Care Center. He has also served as a program director for residents and endocrinology fellows, and as a clerkship director for the Drew/UCLA medical students. Dr. Hsia has been conducting clinical research over the past 13 years, including both industry and investigator-initiated trials, and has been funded by grants from National Institutes of Health and the American Diabetes Association. He has also published original research, book chapters, review papers and CME programs on the management of lipid disorders, insulin resistance, and diabetes mellitus.

Robert A Jenders, M.D., Primary Principal Investigator

Robert A Jenders, MD, MS, FACP, FACMI is Professor of Medicine and Co-Director of the Center for Biomedical Informatics at Charles Drew University and is Health Sciences Clinical Professor of Medicine and Associate Director of the Clinical and Translational Science Institute at the University of California, Los Angeles. A native of Milwaukee, Wisconsin, he received his undergraduate degree in computer science from Marquette University; completed his MD degree and did his medical residency at the University of Wisconsin-Madison; earned a master’s degree in computer science at Northeastern University; and completed a postdoctoral fellowship in biomedical informatics at Harvard University and the Massachusetts General Hospital. He is board-certified in internal medicine and clinical informatics, and he teaches in the residency training program and provides primary care at Harbor-UCLA Medical Center.

Funded by the National Institutes of Health (NIH), his research focuses on clinical decision support and other aspects of the application of information technology in clinical care. He has published numerous scientific papers and book chapters as well as lectured internationally on this topic. He serves on scientific study section panels for NIH and the US Agency for Healthcare Research and Quality (AHRQ) as well as reviews scientific papers for leading journals in biomedical informatics. He leads international efforts to develop health information technology standards as a committee co-chair in Health Level Seven International (HL7). His work at National Research Institute focuses on studies of treatment for diabetes and hypertension. Apart from his professional activities, he is an avid private pilot.

Parvin Syal, M.D., Primary Principal Investigator

Parvin Syal, M.D., completed his undergraduate studies at the University of Nairobi, Kenya and received his MBChB (medical degree equivalent in US) from Cambridge University, England. After extensive global medical training in England and Canada, Dr. Syal spent a semester performing community medicine in low income areas of Bombay, India. Dr. Syal’s medical training includes Internal Medicine, Surgery, Pediatrics, Orthopedics, Emergency Medicine among many other specialties.

Dr. Syal is a highly experienced and well recognized physician with industry teaching appointments and numerous publications. He has over 20 years of research experience both as a Principle Investigator and Sub Investigator. Dr. Syal is Medical Director and Owner of a local weight loss center and practices Internal and Family Medicine in the Van Nuys and Panorama City area. Dr. Syal treats patients with medical conditions such as Diabetes, Obesity, Binge Eating Disorder, Depression, Anxiety, Alzheimer’s Disease, Parkinson’s Disease, Cardiovascular Disease and many others. Dr. Syal has worked with NRI for over 12 years.

Tshekedi G. Dennis, M.D., F.A.P.A., Principal Investigator

Dr. Dennis is a board-certified Psychiatrist who has over ten years of research experience as an Investigator as well as 20 plus years in clinical medicine. He has conducted dozens of studies in indications such as Depressive Disorders, Post-Traumatic Stress Disorder (PTSD), General Anxiety, Schizophrenia, Dementia, Addiction and many more.

Dr. Dennis has received recognition as a Fellow of the American Psychiatric Association and as a past recipient of the Faculty of the Year award from the UCLA-Kern Medical Center. In the Southern California community, Dr. Dennis is an Assistant Clinical Professor of Psychiatry & Neuroscience at UCR SOM (University of California Riverside School of Medicine). He continues to be active with patient care as well as psychiatry education and training. NRI is happy to welcome him to our Investigator and Medical teams!

Rea Abaniel, MS, PA-C

Rea Abaniel, MS, PA-C is a nationally certified physician assistant. Rea earned her Master of Science from Western University of Health Sciences in Pomona, California. She holds a Bachelor of Science in Business Administration with a concentration in Finance from the University of California at Berkeley. She practices at the UCLA Playa Marina urgent care clinic where she serves a variety of clinical needs. Rea serves as a Sub-Investigator for National Research Institute. She is a member of California Academy of Physician Assistants.

Tricia Leon, Nurse Practitioner

Tricia Leon is a Nurse Practitioner having graduated with a MSN from California State University Long Beach. She received a B.S. in Nursing from University of Southern California where she graduated cum laude. Tricia serves as a Sub-Investigator for National Research Institute in a variety of different therapeutic areas including Metabolic and Cardiovascular Diseases and Women’s Health.

John Nelson, PA-C

John Nelson, PA-C, is a skilled Physician Assistant with over 20 years of medical and clinical research experience in a variety of indications such as Pulmonary Medicine and Critical Care, Internal Medicine, Gastroenterology, Infectious Disease, Emergency Medicine, and Geriatrics. He obtained his Physician Assistance certification from USC School of Medicine, PA Program. John currently serves as a Sub-Investigator for multiple sites at National Research Institute and is a member of the California Academy of Physician Assistants.