CTT Leadership

Leisel Koerber, BBA, CCRC

Executive Vice President

Leisel Koerber, BBA, CCRC

Executive Vice President

Leisel Koerber is Executive Vice President at Clinical Trials of Texas. Since 2006, she has held multiple positions in clinical research, including site director and clinical research coordinator. Leisel directs day-to-day operations and strategies, ensuring the success of over 100 studies per year. These trials include first-in-human through Phase IV, dermatology, internal medicine, women’s health, mental health, Alzheimer’s Disease, metabolic disorders, vaccines, healthy population, and device studies.

She has worked on more than 500 trials and was instrumental in the development of a proprietary clinical trial management system (CTMS) and electronic source document software. She has also worked to create and implement quality management systems. Leisel has a BBA from The University of Texas at San Antonio and is a CCRC.

Ayo Avworo, DNP, APRN, FNP, BC, CPI

Assistant Director, Operations

Ayo Avworo, DNP, APRN, FNP, BC, CPI

Assistant Director, Operations

Ayoade Avworo, DNP, APRN, FNP-BC, CPI, is the Assistant Director of Operations and a board-certified Family Nurse Practitioner. She was born in Nigeria and moved to the United States as an international student in 2006. At the University of Texas Health Science Center San Antonio, she earned her bachelor’s, master’s, and doctoral degrees in nursing. She has practiced nursing for more than 7 years and is passionate about quality, safety, and excellence in nursing care. Dr. Avworo is a member of the American Association of Nurse Practitioners, Texas Nurse Practitioners, and Sigma Theta Tau International – Honor Society of Nursing. In 2017, Dr. Avworo was recognized as a “Top Family Nurse Practitioner in San Antonio” by the International Nurses Association.

Douglas Denham, DO, CPI

Chief Medical Director

Douglas Denham, DO, CPI

Chief Medical Director

Douglas Scott Denham, DO, CPI, is Chief Medical Director of Clinical Trials of Texas and is board-certified in family medicine, with more than 25 years of experience. He has served as Principal Investigator on more than 700 studies in the areas of diabetes, fatty liver, healthy volunteers, hyperlipidemia, seasonal allergies, vaccines, growth hormone, diabetic peripheral neuropathy, implantable devices, insulin pumps, clamp studies, renal studies, and more. His experience includes Phase I-IV protocols, including first-in-human studies.

At the University of North Texas Health Science Center, Texas College of Osteopathic Medicine, Dr. Denham earned his Doctoral degree in Osteopathic Medicine. He completed his residency at the University of Texas Health Science Center at San Antonio.

Staci Poettgen, BS

Director, Compliance

Staci Poettgen, BS

Director, Compliance

Staci Poettgen, Director of Compliance at Clinical Trials of Texas, oversees the Regulatory, Training, QA, and QC departments.  She started her clinical research career as a clinical research coordinator for a pharmaceutical company.  Staci came to CTT, leveraging her experience as a clinical research associate for a CRO and then as a project manager for a medical device company.  She was born and raised in San Antonio, Texas, and is a graduate of Texas A&M University with a degree in Biomedical Science.  At CTT, she has expanded the QC/QA and Regulatory departments and helped manage the development of CTT’s first Training Department, which provides onboarding training as well as ongoing clinical and non-clinical skills and personal development for the staff.

Monica Landin

HR

Monica Landin

HR

Monica Landin, HR, is a professional with 20+ years in the healthcare industry with 10 years being in management.  She has worked across multiple industries from retail to healthcare and life sciences in both small and medium-sized companies. Monica has experience within Human Resources including employee relations, full-cycle recruiting, onboarding/training, performance management, compensation/payroll, federal and state law compliance, and benefits. Monica enjoys being outdoors and making memories with her family in her free time.

Meet the Investigators

Douglas Denham, DO, CPI

Chief Medical Director

Douglas Denham, DO, CPI

Chief Medical Director

Douglas Scott Denham, DO, CPI, is Chief Medical Director of Clinical Trials of Texas and is board-certified in family medicine, with more than 25 years of experience. He has served as Principal Investigator on more than 700 studies in the areas of diabetes, fatty liver, healthy volunteers, hyperlipidemia, seasonal allergies, vaccines, growth hormone, diabetic peripheral neuropathy, implantable devices, insulin pumps, clamp studies, renal studies, and more. His experience includes Phase I-IV protocols, including first-in-human studies.

At the University of North Texas Health Science Center, Texas College of Osteopathic Medicine, Dr. Denham earned his Doctoral degree in Osteopathic Medicine. He completed his residency at the University of Texas Health Science Center at San Antonio.

Ayo Avworo, DNP, APRN, FNP, BC, CPI

Assistant Director, Operations

Ayo Avworo, DNP, APRN, FNP, BC, CPI

Assistant Director, Operations

Ayoade Avworo, DNP, APRN, FNP-BC, CPI, is the Assistant Director of Operations and a board-certified Family Nurse Practitioner. She was born in Nigeria and moved to the United States as an international student in 2006. At the University of Texas Health Science Center San Antonio, she earned her bachelor’s, master’s, and doctoral degrees in nursing. She has practiced nursing for more than 7 years and is passionate about quality, safety, and excellence in nursing care. Dr. Avworo is a member of the American Association of Nurse Practitioners, Texas Nurse Practitioners, and Sigma Theta Tau International – Honor Society of Nursing. In 2017, Dr. Avworo was recognized as a “Top Family Nurse Practitioner in San Antonio” by the International Nurses Association.

Parke Hedges, MD

Principal Investigator

Parke Hedges, MD

Principal Investigator

Principal Investigator

Dr. Parke Hedges was born in Arkansas and spent his childhood years in Indiana. His family moved to Texas in 1969 and settled in the Houston area. After graduation from La Porte High School, Dr. Hedges attended Texas A&M University in College Station.

Dr. Hedges completed his internship at University of Texas Health Science Center at San Antonio. Dr. Hedges is affiliated with Methodist Hospital. He completed his residency in obstetrics and gynecology in 1986. He established his first private practice in Corpus Christi, but eventually returned to San Antonio. He is one of the founding members of Seven Oak’s Women’s Center. He has been honored by induction into the AOA Medical Honor Society. Dr. Hedges has also served as Chairman of the Department of Obstetrics and Gynecology or Methodist Hospital.

Dr. Hedges maintains an active private life spending time with his wife Donna and 3 Australian Shepherds. He is an avid orchid grower and active singer songwriter.

Dr Hedges has been honored by his selection to:

  • Consumer Research Council of America – 2012
  • America’s Top Obstetrician and Gynecologists 2002-2003, 2005-2006, 2007-2008, 2011-2012
  • Best Doctors in America 1996-2011
  • Texas Monthly – Texas Super Doctors 2008, 2009, and 2010
  • Patient Choice Award 2009 and 2010

Pendleton Wickersham, MD

Principal Investigator

Pendleton Wickersham, MD

Principal Investigator

Pendleton B. Wickersham was born in Augusta, Georgia in 1975. After graduating magna cum laude from Rice University in 1996, he attended Baylor College of Medicine in Houston and earned his medical degree with honors in 2000. Dr. Wickersham then moved to Denver to complete his post-graduate studies. He completed his internship, residency, and fellowship at University of Colorado Health Sciences Center in Denver. He is board-certified in both internal medicine and rheumatology. Dr. Wickersham moved to San Antonio in early 2006 to pursue his dream of a thriving clinical practice. He is a partner in the San Antonio-based Arthritis Associates, PA. He is a frequent speaker and consultant and he has invented several medical devices. He enjoys exercising outdoors, reading, and fishing.

Terri Nutt, MD

Principal Investigator

Terri Nutt, MD

Principal Investigator

Dr. Terri Nutt is a graduate of the prestigious and highly competitive B.S./M.D. program of Northeast Ohio College of Medicine, earning her Medical Degree in 1995. Upon graduation from medical school, she served 12 years with the US Air Force. She has served as a Flight Surgeon with Air Force Special Operations Command, Hurlburt Field, Florida and as Chief of Dermatology, Travis AFB, California. Her military honors include the Air Force Achievement Medal, Air Force Commendation Medal, Meritorious Service Medal, National Defense Service Medal, Air Force Outstanding Unit Award with Valor, and the Global War on Terrorism Service Medal. She completed her residency in Dermatology at San Antonio Uniformed Services Health Education Consortium in San Antonio, TX. After leaving the military in 2007, Dr Nutt has called San Antonio home and has been practicing at her current location since 2009. Dr. Terri Nutt is a Diplomate of the American Board of Dermatology and a Fellow of the American Academy of Dermatology. She is a member of the Texas Medical Association and the Bexar County Medical Society.

Barbara Corral, MSN, MA, APRAN, FNP-BC

Assistant Director, Early Phase Services/Investigator

Barbara Corral, MSN, MA, APRAN, FNP-BC

Assistant Director, Early Phase Services/Investigator

Barbara Corral started her career in research in 2007 working at The Center for Molecular and Behavioral Neuroscience at Rutgers University in academic research, where she had multiple publications. This experience sparked her interest in the medical profession and she decided to go to nursing school for her BSN. Barbara started her career at Jackson Memorial Hospital in Miami, FL, a level I trauma center, as a trauma nurse in 2011 and obtained her Family Nurse Practitioner license in 2015. As a Nurse and a Nurse Practitioner, she had the opportunity to work in multiple specialties.  She is a well-rounded Family Nurse Practitioner with extensive experience in emergency, adult, pediatric and psychiatric medicine. She is currently working on her Doctor in Nursing Practice – Health Leadership Track, graduating in 2023. She has been working in clinical trials since 2019 in both early and late phase trials in leadership positions and as an investigator.

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