Our Team and Mission
Axiom Brain Health is a clinical research site that has been providing exceptional, concierge-level attention to residents in the Tampa-area for 30+ years. We specialize in conducting Phase II-IV neurological clinical trials, such as Alzheimer’s, Parkinson’s, and Multiple Sclerosis, in a comfortable outpatient setting.
Mark C. Cascione, M.D.
Dr. Cascione received his Doctorate in Medicine in 1991 from University of Vermont College of Medicine. After completing residencies at Maine Medical Center, Portland, Maine (1992) and Duke University Medical Center, Durham, North Carolina (1995), he received his Board Certification in Neurology & Psychiatry in 1997 and in Electrodiagnostic Medicine in 1998. Dr. Cascione joined Tampa Neurology Associates and Axiom Clinical Research of Florida in 1996, subsequently becoming a partner in both companies. He is on staff at St. Joseph’s, Memorial Hospital of Tampa, St. Joseph’s Women’s Hospital and Tampa General. Dr. Cascione is a national and international thought-leader and educator for treatment and research topics in Multiple Sclerosis.
Susan J Steen, M.D.
Dr. Steen graduated from the University of Florida Medical School in 1978, served her residency in University of South Florida and affiliated hospitals and completed her Neurology residency at the University of Florida, Gainesville, receiving Board Certification in Medicine & Surgery in 1979 and in Neurology and Psychiatry in 1991. She joined Tampa Neurology Associates in 1983, becoming a partner shortly thereafter, and is a co-founder (1993) and president of Axiom Clinical Research of Florida Dr. Steen is a renowned speaker for Alzheimer’s Disease, and is the medical advisor to multiple memory loss facilities. She is on staff at St. Joseph’s, Memorial Hospital of Tampa, St. Joseph’s Women’s Hospital and Tampa General.
Kaden Appleberry
Kaden completed his schooling at Eastern College of Health Vocations in Little Rock, Arkansas. In his two years at Axiom, he has focused on clinical trials for Alzheimer’s disease and mild cognitive impairment.
Kaden finds the ever-evolving field of science and medicine one of the best parts of the job, and hopes that community members find the Axiom team trustworthy and dependable.
Though he thought he would grow up to be a baseball coach, he instead became a dog dad who (according to his dog) lives a second life as a clinical researcher.
Johanna Carmona
Johanna completed her Nursing degree in Puerto Rico in 2017 during Hurricane Maria despite being without electricity or power for five months. She started her clinical research journey in 2011 after receiving her CPN license, where she then applied to work at an Internal Medicine private practice in Puerto Rico. Being a bilingual speaker, she was able to translate and help patients understand research.
Though she joined Axiom in June 2024, she is responsible for coordinating Alzheimer’s, Parkinson’s, and multiple sclerosis clinical trials. She also helps with infusions of investigational medications.
Johanna loves animals and tries to visit the zoo’s or U.S. National Park’s when she travels.
Marline Denis
Marline attended the University of Florida and received a BA in African American Studies, and it was also where she was first introduced to research. She then went to the University of Arizona for Masters in Public Health and is currently attending Walden University for her Doctorate of Public Health. She joined the Axiom team in 2024.
Her involvement in research began with the hope to provide clarity to communities with a negative history surrounding clinical trials. She seeks to advocate for all the good work accomplished through clinical research and by the people who volunteer. Her role at Axiom is to support regulatory and compliance for the clinical trials, and to support the SNAP (Swift Neurological Assessment Program) free memory screening program.
When she’s not working, you can find Marline walking the Tampa Riverwalk looking for her favorite foods curry and roti or parmesan truffle fries with garlic aioli.
Johannes Dessoy
Johannes is originally from Germany and studies at Eberhard Karls University Tuebingen and is a German Board Certified Anesthesiologist. A desire to make a bigger impact on patient lives, in the last year he switched to clinical research and has been at Axiom Brain Health for several months. He hopes that the network of different professionals at ABH makes a change in the lives of those in the community.
At Axiom, Johannes supports clinical ratings for trials for Alzheimer’s and multiple sclerosis, supports the SNAP (Swift Neurological Assessment Program) free memory screening program, and supports community-based screening programs
Johannes enjoys spending time outside, particularly at the beach with his wife and daughter or playing rugby.
Ellen Frinks
Ellen has been working at Axiom Brain Health for seven years and has been involved in clinical research for nearly 20. She attended the University of Hawaii and received a degree in Bioengineering, the University of Phoenix for her Masters in Healthcare Administration, and Fortis College for an ADN in Nursing. Her clinical background began in preclinical trials for non-human primates.
She leads the research team at Axiom and hopes that it is a beacon of hope for people in the community who are living with neurodegenerative diseases. With much of the work they do focusing on the individual, Ellen finds it an honor to be a part of the patient and their family’s stories.
Ellen’s mother used to call her a Witch, as she had dreams of opening a holistic wellness center that focused on plant-based medicine. In her free time, she enjoys spending time outside, especially in the U.S. National Parks or in a hammock, and exploring different art mediums like watercolor.
Chloe Rzeppa
Chloe graduated from the University of Missouri with a B.S. in Psychology and also received certificates in Neuroscience and Multicultural Studies. She has been in the research field for over three years now after a teaching assistant recommended her university’s research lab to answer all the questions she couldn’t find answers to.
As Chloe has recently joined Axiom Brain Health, she enjoys the patient interaction and is excited to see how their clinic will impact seniors in the community. She supports Axiom’s clinical trials in multiple sclereosis, as well as our Alzheimer’s prescreening programs.
After a long day, you can find her spending time with her cat, reading, cooking, or spending time outdoors hiking and exercising.