Expertise that shapes every study.
Every study opportunity is evaluated through the lens of experienced investigators who understand both patient care and research delivery.
Their insight helps align protocols with site capabilities, patient populations, and therapeutic expertise, creating stronger study execution from the start.
The result is research informed by real-world clinical experience and delivered with the consistency sponsors expect.
Investigator judgment,
built into the network.
Our Investigator Advisory Board puts PhaseWell's leading PIs at the center of how the network runs. They review protocols before we take them on, develop the next generation of PIs, and shape the standards every site runs on.
Evaluating study design and operational feasibility before trials are accepted.
Growing the next generation of PIs across our sites.
Informing how PhaseWell selects trials and builds toward pragmatic, executable research.
Meet PhaseWell's Investigators.
The experienced clinical investigators who run our studies, rooted in the communities they serve.
Ashok Patel, MD
Principal Investigator
Dr. Ashok Patel is a board-certified psychiatrist with added qualifications in geriatric psychiatry. As the founder of Bio Behavioral Health in Toms River, New Jersey, he has over 30 years of experience in clinical trials of major depressive disorder, treatment-resistant depression, bipolar depression, generalized anxiety disorder, Alzheimer’s disease, dementia-related agitation and psychosis, Parkinson’s disease psychosis, and migraine.
Dr. Patel earned his medical degree from Kasturba Medical College in India, completed his psychiatry residency at St. Vincent’s Medical Center in New York, where he served as Chief Resident, and completed a fellowship in geriatric psychiatry at Cornell University Medical College. He previously served as Clinical Assistant Professor of Psychiatry at UMDNJ–Robert Wood Johnson Medical School and received the Alzheimer’s Association New Jersey Chapter Humanitarian of the Year award.
Carlos Sariol, MD, FACP
Latin Clinical Trial Center
Carlos Sariol, MD, FACP
Principal Investigator
Dr. Carlos Sariol is a physician-scientist trained in infectious diseases and virology who founded Latin Clinical Trial Center in San Juan, Puerto Rico, in 2006 and serves as its lead Principal Investigator. Under his leadership, the site has conducted more than 85 clinical studies across Phase II–IV. He has served as Sub-Investigator on more than 65 studies in diabetes, obesity, NASH/MASH, lupus, rheumatoid arthritis, and cardiovascular disease, and as Principal Investigator on trials in hypertension, cardiovascular risk reduction, type 2 diabetes, and dengue and Zika vaccines.
Dr. Sariol earned his medical degree from the Institute of Medical Sciences in Havana and completed a fellowship in infectious diseases and a master’s degree in virology at the Pedro Kourí Institute of Tropical Medicine. He previously directed the Virology Laboratory at the Caribbean Primate Research Center at the University of Puerto Rico School of Medicine. He has authored more than 30 peer-reviewed publications, is licensed to practice medicine in Puerto Rico and Florida, and is a Fellow of the American College of Physicians (FACP).
David Brown, MD
Principal Investigator
Dr. David Brown is board certified in psychiatry and neurology. He founded Community Clinical Research in Austin, Texas, in 1994 and has served as its Principal Investigator ever since. With over 30 years of experience, Dr. Brown has overseen more than 400 clinical trials, with depth in schizophrenia, as well as bipolar disorder, major depressive disorder, and Alzheimer’s disease, across Phase I through Phase III. He has co-authored publications in Schizophrenia Bulletin, the Journal of Clinical Psychiatry, and International Clinical Psychopharmacology.
Dr. Brown earned his medical degree and completed his psychiatry residency at the University of Texas Medical School at Houston, followed by a fellowship in the Biological Psychiatry Branch of the National Institute of Mental Health, where he trained in clinical drug trials and quantitative EEG. He previously served as Assistant Professor of Psychiatry at the University of Arkansas for Medical Sciences, is certified on a broad range of neuropsychiatric rating scales, and is bilingual in English and Spanish.
John Nardandrea, MD
Principal Investigator
Dr. John Nardandrea is a board-certified physician with more than 35 years in internal medicine and more than 25 years conducting clinical trials. He has served as Principal Investigator on more than 100 studies and as Sub-Investigator on more than 250, advancing treatments in Alzheimer’s disease and other neurodegenerative disorders, diabetes and obesity, chronic pain, cardiovascular disease, migraine, and infectious diseases. His recent work includes Phase II and Phase III trials of investigational therapies for early Alzheimer’s disease.
Dr. Nardandrea earned his undergraduate and medical degrees from the University of Florida and completed his internship and residency at Tallahassee Regional Medical Center. He is board certified in family practice, hospice, and palliative medicine and is a past President of the Marion County Medical Society.
Joseph Soufer, MD
Principal Investigator
Dr. Joseph Soufer is a board-certified internist with fellowship training in endocrinology and more than 25 years of experience leading clinical research. As lead Principal Investigator and founder of Chase Medical Research, he has participated in nearly 450 clinical studies spanning diabetes, obesity, dyslipidemia, hypertension, cardiovascular and kidney disease, osteoarthritis and neuropathic pain, osteoporosis, vaccines, and women’s health, including recent Phase III programs in obesity, type 2 diabetes, and lipid lowering.
Dr. Soufer earned his medical degree from the University of Brussels Medical School in Belgium, completed his internal medicine residency at Yale New Haven Hospital, and completed an endocrinology fellowship at Memorial Sloan Kettering Cancer Center. He served as Assistant Clinical Professor of Medicine at Yale University School of Medicine from 1994 to 2004 and is a past President of the American Diabetes Association’s Northwestern Chapter in Connecticut.
Nashat Gabrail, MD
Principal Investigator
Dr. Nashat Gabrail is a medical oncologist and hematologist who has led Gabrail Cancer Center in Canton, Ohio, since 1990, specializing in early-phase and bioequivalence oncology studies. He also leads the Gabrail Phase 1 Research Center and has helped build a network that brings industry-sponsored trials to community oncology practices. His work spans solid tumors and hematologic malignancies, with more than 100 publications and abstracts in journals including The Lancet Haematology and Blood.
Dr. Gabrail earned his medical degree from Mosul College of Medicine and is a member of the Royal College of Physicians (UK) and the Royal College of Pathologists. He completed an internal medicine residency at Hurley Medical Center and a hematology/oncology fellowship at the University of Missouri, then served as Assistant Professor of Medicine at Saint Louis University. He serves on the Board of the Community Oncology Alliance and consults with sponsors and CROs on protocol design.
Alex Gonzalez, MD, FACP, FACE
Principal Investigator
Dr. Alex Gonzalez is a board-certified endocrinologist and certified lipid specialist who has served as Principal Investigator at Latin Clinical Trial Center since 2019. He has led 12 trials as Principal Investigator and served as Sub-Investigator on additional studies, focusing on type 2 diabetes, obesity, lipoprotein(a), and cardiovascular risk reduction, including Phase III programs for tirzepatide, retatrutide, orforglipron, and maridebart cafraglutide. He is Associate Program Director of the Endocrinology Training Program at San Juan City Hospital and President of AG Thyroid & Endocrine Clinic.
Dr. Gonzalez graduated cum laude from Universidad Central del Caribe School of Medicine and completed his internal medicine residency and an endocrinology research fellowship at the University of Puerto Rico School of Medicine, followed by an endocrinology fellowship at San Juan City Hospital. He is board certified in internal medicine and in endocrinology, diabetes, and metabolism and is a Fellow of the American College of Physicians (FACP) and the American College of Endocrinology (FACE).
Anette Nieves, MD
Renstar Medical Research
Anette Nieves, MD
Principal Investigator
Dr. Anette Nieves is a fellowship-trained movement disorders neurologist who has conducted clinical research with Renstar Medical Research since 2007. She has served as Principal Investigator on more than 55 studies and as Sub-Investigator on more than 40, with a focus on Parkinson’s disease, Alzheimer’s disease, Lewy body dementia, and migraine. She practices at Neurological Specialists of Central Florida in Ocala and is a Parkinson Study Group investigator.
Dr. Nieves earned her medical degree from the University of Puerto Rico School of Medicine, completed her neurology residency at the University of Medicine and Dentistry of New Jersey, where she served as Chief Resident, and completed a movement disorders fellowship at the University of Toronto’s Toronto Western Hospital. She then served as Assistant Professor of Neurology at UMDNJ–Robert Wood Johnson Medical School before entering practice in Ocala. A member of the American Academy of Neurology, she is fluent in English and Spanish.
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Ashish Adlakha, MD
Principal Investigator
Dr. Ashish Adlakha is a board-certified neurologist with additional certifications in sleep medicine, electrodiagnostic medicine, and headache medicine, with more than 15 years of clinical experience. A Principal Investigator at Chase Medical Research since 2025, he has served as Sub-Investigator on more than 30 industry-sponsored trials in obesity, diabetes, cardiovascular disease, and dyslipidemia, and has consulted for the Institute of Neurodegenerative Disorders on early dementia and Parkinson’s disease research. He is experienced with neurological rating scales including the UPDRS, CDR, MoCA, ADAS-Cog, and MIDAS.
Dr. Adlakha earned his medical degree from Maulana Azad Medical College in New Delhi, India, and completed residencies in internal medicine at St. Francis Hospital in Evanston, Illinois, and in neurology at Tufts University, followed by a sleep medicine fellowship at Seton Hall University. He is an Attending Neurologist and Assistant Professor at the University of Connecticut and previously served as Attending Neurologist and Site Director for the Headache Centers of Excellence at VA Connecticut.
Ashley Cauthen, MD
Principal Investigator
Dr. Ashley Cauthen is a board-certified dermatologist who has conducted clinical research with Renstar Medical Research since 2014, serving as Principal Investigator on more than 50 studies and as Sub-Investigator on more than 15. Dr. Cauthen’s research has particular depth in moderate-to-severe plaque psoriasis, including biologic and biosimilar programs, as well as atopic dermatitis, hidradenitis suppurativa, rosacea, and actinic keratosis. Dr. Cauthen has practiced at MidState Skin Institute in Ocala since 2013.
Dr. Cauthen earned a Bachelor of Science in biology from the University of South Florida and a medical degree from Florida State University College of Medicine, then completed an internal medicine internship and dermatology residency at the University of South Florida College of Medicine. A member of Alpha Omega Alpha, Dr. Cauthen has also served as a dermatologist at the James A. Haley Veterans Affairs Hospital in Tampa and is a member of the American Academy of Dermatology and the American Society for Dermatologic Surgery.
Carlos Pantojas, MD
Latin Clinical Trial Center
Carlos Pantojas, MD
Principal Investigator
Dr. Carlos Pantojas is a rheumatologist and internist with more than 35 years in private practice in Puerto Rico and extensive experience in autoimmune disease research at Latin Clinical Trial Center. He has participated in nearly 20 industry-sponsored trials in systemic lupus erythematosus, rheumatoid arthritis, osteoarthritis pain, and other inflammatory conditions, including Phase II and Phase III programs for deucravacitinib, obexelimab, and peresolimab. He co-authored a 2018 publication in Rheumatology on baricitinib response in refractory rheumatoid arthritis.
Dr. Pantojas earned his medical degree from Universidad Central del Caribe and completed his internship, internal medicine residency, and rheumatology fellowship at San Juan City Hospital. He previously served as Assistant Professor of Internal Medicine at San Juan Bautista School of Medicine and as Rheumatology Consultant at Caguas Regional Hospital, and he has chaired the Scientific Committee of the Puerto Rico Rheumatology Association. He is a member of the American College of Rheumatology and the American College of Physicians.
David Oliver, DO
Principal Investigator
Dr. David Oliver is an osteopathic family physician who has conducted clinical research with Renstar Medical Research since 2005. He has served as Principal Investigator on more than 20 studies and as Sub-Investigator on more than 15, in areas including diabetes, dyslipidemia, osteoarthritis and chronic pain, opioid-induced bowel dysfunction, and vaccines. He practices with American Family Medical in Ocala and served as Chairman of the Department of Family Medicine at AdventHealth Ocala from 2022 to 2024.
Dr. Oliver earned his Doctor of Osteopathic Medicine degree from the West Virginia School of Osteopathic Medicine and completed his osteopathic family practice residency at Columbia Medical Center–Peninsula in Ormond Beach, Florida, where he served as Chief Resident. He has held adjunct faculty appointments at Nova Southeastern University and Lincoln Memorial University. He is a member of the American Osteopathic Association, the American College of Osteopathic Family Practice, and the Florida Osteopathic Medical Association.
James Doney, MD
Principal Investigator
Dr. James Doney is a board-certified internist who joined Chase Medical Research as a Principal Investigator in 2026, bringing hospital medicine experience from Hartford Hospital and Griffin Hospital. He has served as Sub-Investigator on more than 30 trials focused on cardiovascular outcomes, lipoprotein(a) and LDL cholesterol lowering, hypertension, heart failure, obesity, and knee osteoarthritis, as well as influenza vaccine research.
Dr. Doney earned a Bachelor of Arts in biological sciences from Warner University and his medical degree from St. George’s University, and completed his internal medicine residency at UPMC Mercy in Pittsburgh. He has practiced as a hospitalist attending physician with Hartford Hospital Medical Group since 2019 and served as a teaching inpatient hospitalist at Griffin Hospital in Derby, Connecticut, from 2022 to 2025, where he worked with physicians in training.
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Jenna Langello, PA-C
Principal Investigator
Jenna Langello, PA-C, is a certified physician assistant with clinical experience in cardiology, internal medicine, and urgent care. Langello joined Chase Medical Research in 2021 as a Clinical Research Coordinator and now serves as a Principal Investigator on numerous studies. She has supported more than 75 clinical trials, including as Principal Investigator on Phase III retatrutide studies in obesity, type 2 diabetes, cardiovascular disease, and knee osteoarthritis, with additional experience in vaccines, chronic kidney disease, and chronic pain.
Langello earned a Bachelor of Science in biology, cum laude, from Clark University and a Master of Health Sciences from the Duke University Physician Assistant Program. Before joining Chase Medical Research, she practiced with Advanced Cardiovascular Specialists and St. Vincent’s Medical Center in Bridgeport, Connecticut, as well as in urgent care. She is a member of the American Academy of Physician Assistants.
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Jillian Reid, DNP
Principal Investigator
Jillian Reid, DNP, is a board-certified adult-gerontology primary care nurse practitioner with clinical experience in internal medicine. Reid joined Chase Medical Research in 2023 as a Clinical Research Coordinator and now serves as a Principal Investigator. She has supported 30 clinical trials, serving as Principal Investigator on studies in lipoprotein(a) and cardiovascular outcomes, severe hypertriglyceridemia, and obesity with type 2 diabetes, and as Sub-Investigator on trials in diabetes, obesity, cardiovascular disease, diabetic peripheral neuropathic pain, migraine, and vaccines.
Reid earned her Bachelor of Science in Nursing and Doctor of Nursing Practice from Quinnipiac University and holds Adult-Gerontology Primary Care Nurse Practitioner certification from the American Nurses Credentialing Center. Before joining Chase Medical Research, she practiced as a nurse practitioner with Quinnipiac Internal Medicine and Impact Health and as a registered nurse at Bridgeport Hospital. She has also authored patient education articles on cardiovascular disease, obesity, and lipoprotein(a).
Jose Rivera-Acosta, MD
Latin Clinical Trial Center
Jose Rivera-Acosta, MD
Principal Investigator
Dr. Jose Rivera-Acosta is a gastroenterologist and transplant hepatologist who has served as Principal Investigator at Latin Clinical Trial Center since 2018. His research focuses on nonalcoholic steatohepatitis (NASH/MASH) and NASH cirrhosis, including Phase II and Phase III trials of resmetirom, obeticholic acid, efinopegdutide, and other investigational therapies, as well as Crohn’s disease. He has also served as Principal Investigator at Hospital Auxilio Mutuo for the Phase III REGENERATE study of obeticholic acid in NASH.
Dr. Rivera-Acosta earned his medical degree magna cum laude from the University of Puerto Rico School of Medicine, where he completed his internal medicine residency, serving as Chief Resident, and his gastroenterology fellowship. He completed a liver transplant hepatology fellowship at Emory University and is Assistant Professor of Medicine in the University of Puerto Rico’s Gastroenterology Division and a member of the gastroenterology and liver transplant hepatology faculty at Hospital Auxilio Mutuo.
Raj Karunakara, MD, FCCP
Renstar Medical Research
Raj Karunakara, MD, FCCP
Principal Investigator
Dr. Raj Karunakara is a board-certified pulmonary, critical care, and sleep medicine physician who has served as Medical Director of Ocala Lung & Critical Care Associates and the Sleep Center of Ocala since 2003. A Renstar Medical Research investigator since 2011, he has served as Principal Investigator on 32 clinical trials in COPD, idiopathic pulmonary fibrosis, obstructive sleep apnea, insomnia, and REM sleep behavior disorder, and his sleep laboratory supports research polysomnography studies.
Dr. Karunakara earned his medical degree from the University of Kerala in India. He completed his internal medicine residency at Unity Health System in Rochester, New York, and fellowships in pulmonary and critical care medicine at SUNY Downstate Medical Center. Certified by the American Board of Internal Medicine in internal medicine, pulmonary medicine, critical care medicine, and sleep medicine, he is a Fellow of the American College of Chest Physicians (FCCP) and Assistant Professor of Internal Medicine at the University of Central Florida College of Medicine.
Samuel Collier, MD
Principal Investigator
Dr. Samuel Collier is a board-certified psychiatrist specializing in complex mood disorders, treatment-resistant depression, and neuromodulation, including ECT, TMS, VNS, and DBS. He joined Community Clinical Research as a Principal Investigator in 2025 and conducts trials in schizophrenia, bipolar disorder, and major depressive disorder. He previously served as Principal Investigator on trials of VNS therapy and AXS-05 for treatment-resistant depression and as Sub-Investigator on a deep brain stimulation trial in Alzheimer’s disease.
Dr. Collier earned his medical degree from the University of Texas Medical School at Houston and completed his psychiatry residency at the University of Pennsylvania. During a decade on the faculty of UT Southwestern at Austin and UT Dell Medical School, where he rose to Associate Professor, he directed the Treatment Resistant Depression Integrated Practice Unit and the ECT Service at Ascension Seton. He is a Fellow of the American College of Psychiatrists and has co-authored textbook chapters on treatment-resistant depression.
Shilpa Shetty, MD
Chase Medical Research
Shilpa Shetty, MD
Principal Investigator
Dr. Shilpa Shetty is a board-certified endocrinologist and internist who joined Chase Medical Research as a Principal Investigator in 2026. She has served as Sub-Investigator on more than 20 trials in obesity, type 2 diabetes, dyslipidemia, hypertension, cardiovascular disease, and chronic pain, including diabetic peripheral neuropathic pain, low back pain, and osteoarthritis pain. She practices with Endocrine Associates of Connecticut in Hamden and serves as a Clinical Instructor in the Department of Medicine at Yale University.
Dr. Shetty earned her medical degree from Kasturba Medical College in India, completed her internal medicine internship and residency at Griffin Hospital in Derby, Connecticut, and completed a fellowship in endocrinology at UT Southwestern Medical Center in Dallas. She previously served as Assistant Professor of Medical Sciences at Quinnipiac University. She has published in Endocrine Practice and The Journal of Clinical Endocrinology & Metabolism and is a member of the Endocrine Society.
Sidney Clevinger, MD
Principal Investigator
Dr. Sidney Clevinger is a board-certified family medicine physician with more than 35 years in practice who has conducted clinical research with Renstar Medical Research since 1999. He has served as Principal Investigator on more than 140 studies and as Sub-Investigator on more than 240, spanning diabetes, chronic pain conditions including osteoarthritis, fibromyalgia, and diabetic neuropathy, Alzheimer’s disease, psoriasis, dyslipidemia, and hypertension. He is Medical Director of Family Care Specialists in Ocala and has served as President of the Medical Staff at Munroe Regional Medical Center.
Dr. Clevinger earned his medical degree from Ross University School of Medicine and completed his family practice residency through New York Medical College at St. Joseph Medical Center in Yonkers, New York. Certified by the American Board of Family Practice, he has served as medical director for numerous rehabilitation, home health, and geriatric care programs. He is a member of the American Geriatrics Society and the American Medical Directors Association and speaks English and Spanish.
Hamdy Mohtaseb, MD, FACP
Principal Investigator
Dr. Hamdy Mohtaseb is a board-certified medical oncologist and internist who also specializes in hematology, with more than 25 years of experience in hematology and oncology care. He has led Mohtaseb Cancer Center & Blood Disorders in Bullhead City, Arizona, and Henderson, Nevada, since 2009, and has served as a Principal Investigator at Pioneer Research Center, a PhaseWell Oncology partner site, since 2024. His earlier research on allogeneic immunity and graft-versus-leukemia effects in acute leukemia earned the Cancer Institute of New Jersey’s Gallo Award in 1998.
Dr. Mohtaseb earned his medical degree from Ain Shams University in Cairo, Egypt, and completed his internal medicine residency and hematology/oncology fellowship at Seton Hall University (St. Joseph’s Hospital and Medical Center) in New Jersey. He previously served as Medical Director of the KRMC Cancer Center in Kingman, Arizona. Board certified in internal medicine and medical oncology, he is a Fellow of the American College of Physicians (FACP) and a member of the American Society of Clinical Oncology and the American Society of Hematology.
Keith Lerro, MD, PhD
Carolina Cancer Research Center
Keith Lerro, MD, PhD
Principal Investigator
Dr. Keith Lerro is a board-certified medical oncologist and physician-scientist with more than 20 years of experience in oncology clinical research. He is President and Medical Director of Regional Medical Oncology Center in Wilson, North Carolina, and has served as a Principal Investigator at Carolina Cancer Research Center, a PhaseWell Oncology partner site, since 2024. Earlier in his career, he served as Principal Investigator and Sub-Investigator on Phase II–IV cooperative group trials, including NSABP, CALGB, and ECOG studies, and he has co-authored publications in the Journal of Clinical Oncology.
Dr. Lerro earned his medical degree from Albert Einstein College of Medicine and a PhD in molecular pharmacology from the State University of New York at Stony Brook. He completed his internal medicine residency at Montefiore Medical Center and a fellowship in oncology/hematology at Yale University School of Medicine. A past President of the North Carolina Oncology Association, he is a member of the American Society of Clinical Oncology and the Community Oncology Alliance.
Sumit Sawhney, MD
SSAK Partners
Sumit Sawhney, MD
Principal Investigator
Dr. Sumit Sawhney is a board-certified oncologist, hematologist, and internist who has practiced in Florida since 1997 and has served as President of Oncology and Hematology Associates of West Broward since 2010. He is a Principal Investigator at SSAK Partners, a PhaseWell Oncology partner site in Coral Springs, Florida, and has led nearly 20 clinical trials in breast, colorectal, lung, and pancreatic cancers, aggressive lymphoma, myelodysplastic syndromes, and chemotherapy-induced anemia.
Dr. Sawhney earned his medical degree from University College of Medical Sciences in New Delhi, India, and completed his internal medicine residency and hematology-oncology fellowship at the University of Illinois at Chicago, where he received the Chief Resident’s award. He is board certified in internal medicine, hematology, and oncology. He is a member of the American Society of Clinical Oncology, the American Society of Hematology, and the American College of Physicians.
Why investigators build their research with us.
Clinical research has steadily moved from academic centers into community oncology, and we have been proud to lead that transformation. Partnering with PhaseWell has accelerated it, expanding our ability to bring innovative therapies to more patients while staying rooted in community care.
Partnering with PhaseWell lets me focus on what I love most, delivering impactful care to my memory and movement disorder patients, without the pressures of large health systems. The people at PhaseWell genuinely care about patients, and I trust them to consistently do what is right.
What I value most is the culture of partnership. PhaseWell engages investigators as collaborators, respects clinical judgment, and operates with consistency and integrity. That level of trust makes a meaningful difference in how research is carried out day to day.
Become a PhaseWell investigator.
PhaseWell is a home for investigators who do serious research and care deeply about their patients. Community physicians with deep indication expertise, we'd like to talk.