Where the experts come to work

Since 2011, we’ve been serving our community and the clinical research industry. When you work with the best people, you receive the best care.

Center Leadership

Howard Schwartz, MD

Chief Medical Officer

Dr. Howard Schwartz is the Chief Medical Officer for CenExel RCA and serves as Principal Investigator on Vaccine and Phase I trials and as a Sub-Investigator on most other trials. He has been involved with over 1000 trials in multiple therapeutic areas and attributes his success to combining a well-trained research staff with a skilled Investigator and motivated trial participant. Throughout his career, he has always led with integrity and made sure all members of the team are well trained on GCP and study specific requirements.

Dr. Schwartz is Board Certified in Internal Medicine and Gastroenterology and practiced in South Florida for over 30 years.  He is now focusing on making CenExel RCA the premier research site in South Florida. He has lectured and published extensively on many of the clinical trials in which he has participated.  Additionally, he served as an industry consultant and served on numerous Data Safety Management Boards.

Dr. Schwartz was born in Philadelphia, moved to Florida to attend college and never went home. He is a graduate of the University of Miami Miller School of Medicine where he also completed his Internal Medicine Residency and Gastroenterology Fellowship. He is married with 3 children.  He is an avid sports fan, golfer and boater.

Meet Our Team

Timothy Grant, MD, FAASM

Medical Director

Dr. Timothy Grant, the medical director of the Neurology and Sleep Medicine Divisions at CenExel RCA. Dr. Grant is a board-certified neurologist and sleep specialist, he is widely recognized for his work in neurology and expertise in sleep medicine.

Nelson Cordero-Torres, MD

Principal Investigator

Dr. Cordero has delved into clinical research since starting with CenExel RCA and is currently one of RCA’s Principal Investigators. He has experience with over 50 clinical trials and always maintains abreast on current research in CNS. Dr. Cordero’s experience and leadership pave the way for success in conducting clinical trials at CenExel RCA.

Sandeep Mendiratta, MD

Principal Investigator

Dr. Mendiratta has gained experience in clinical research since beginning his career as a psychiatrist. Dr. Mendiratta has served as sub-investigator for the majority of CenExel RCA’s clinical trials in both the outpatient and inpatient settings for a variety of diagnoses including schizophrenia, ADHD, substance abuse and depression. His expertise in these areas have led to several features in Broward Health’s Monthly Magazine and local television newscasts.

Nelia Sanchez-Crespo, MD

Principal Investigator

Dr. Nelia Sanchez-Crespo is an Internal Medicine Physician graduated Cum Laude from PUCMM in Dominican Republic and completed specialty training in United States at Atlanta Medical Center with high honors. She is Board Certified in Internal Medicine. Dr. Sanchez-Crespo has continued experience thru over 15 years of medical practice. She is an investigator in multiple clinical trials at CenExel RCA and she secures patient care through the research operation. She is fluent in English and Spanish.

Craig Shapiro, DO

Principal Investigator

Dr. Craig Shapiro is board-certified in Otolaryngology, Head and Neck Surgery and Facial Plastic Surgery. He has been practicing in South Florida since 1994. He graduated from The University of Florida with a Bachelor’s in Science. Dr. Shapiro obtained his Doctor of Osteopathic Medicine from Southeastern University of Health Sciences which is currently Nova Southeastern University.

He completed a one-year rotating internship at Botsford General Hospital in Farmington Hills Michigan. Dr. Shapiro completed his ENT and Facial Plastic training at The Philadelphia College of Osteopathic Medicine and Medical College of Pennsylvania in Philadelphia, Pennsylvania. During his time in practice, Dr. Shapiro has held elected positions as Chief of Otolaryngology Department of several hospitals. Now, he is an investigator in multiple clinical trials at CenExel RCA.

Surisaday Mederos


Surisaday Mederos serves as a Sub-Investigator and director of operations at the south office for CenExel RCA. She is a Board-Certified Family Nurse Practitioner and a Certified Clinical Research Coordinator. Suri has over 15 years of experience as a clinical research coordinator and worked on multiple clinical trials in both the inpatient and outpatient setting.

She has practiced in various health settings including, hospitals and private practices. Additionally, Suri has over two years of experience working as a provider for a neurology practice focused on sleep medicine.

Surisaday’s passion is to advocate for her patients and practice using the best evidence available in order to promote and prioritize safety. In addition, she loves to spend time with her family and two children.

Janet Tamayo

Edwin Gomez, MD


Dr. Gomez served as Medical Director, Psychiatrist, Case Manager, Medical Interpreter, and Admissions Specialist at a variety of treatment settings throughout South Florida in both the residential, hospital, laboratory and community based mental health treatment centers.

He is an active member of the American Medical Association and American Psychiatric Association. Dr Gomez speaks English and Spanish.

Janet Tamayo

Maria Companioni, APRN


Maria Companioni has practiced a wide range of settings, including home health, hospitals, and private practices. She has 10 years of experience working with psychiatric disorders.

Maria graduated Magna Cum Laude from her nursing program in 2012. She began with the Acute care, moved to Chronic at South Florida State Hospital, then joined the CenExel RCA CNA team where she specializes in Substance Abuse, Acute Schizophrenia, Bipolar Disorders, Major Depressive Disorders and LGBTQ+ related concerns.

She is a caring and dedicated clinician with excellent patient care management skills and a passion for mental health.

Janet Tamayo

Janet Sentil Tamayo

Board-certified Nurse Practitioner

Janet graduated from Miami Regional University. Professional experience as registered nurse in medical-surgical and telemetry units for Mount Sinai medical center and Memorial hospital Miramar. Professional experience as primary care physician in Havana, Cuba. Highly loyal, team player, with a steadfast commitment to quality care and preventative care advocacy. Disciplined, and confident. Speaks both English and Spanish.
May Fernandez

Mayra (May) Fernandez

Director of Operations

May operates and assumes responsibility as the head of site management and monitors the entire process of Phases I through Phase III of clinical trials. May oversees and directs close to 150 employees and helps to plan, guide and problem-solve clinical research studies across all RCA locations. By facilitating and supporting all studies start-up activities, May is responsible for collaboration efforts with cross functional internal and external teams to successfully conduct trials on schedule, on budget, in compliance, and to the highest quality standards.

May has excellent organizational, analytical, and project management skills. Leading by example and being very passionate about coaching her team to meet and exceed the business goals is what May brings every day to our organization.

Safety and quality are paramount

Our physicians have extensive backgrounds in their respective medical specialties and always prioritize patient safety.




200+ years of collective clinical trial experience


Assisted by expertly-trained medical staff

Early phase unit, late phase space, and sleep lab all adjacent

Having all departments housed in the same location simplifies the process for our patients


Also partnered with Fort Lauderdale Behavioral Health Center to conduct inpatient and outpatient psychiatric trials


On-site PBMC isolation lab certified by Duke University Proficiency Program


RCA Main Facility
7261 Sheridan Street, Suite 210
Hollywood, FL 33024
Monday – Friday    8AM – 5PM

Get Directions

RCA Fort Lauderdale Inpatient Facility
5757 North Dixie Highway
Oakland Park, FL 33334
Monday – Friday    8AM – 5PM

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We’re a CenExel
Center of Excellence

Centers of Excellence provide unparalleled attention to detail to assure consistent and first-class quality in patient care. We have supported tens of thousands of studies, the variety and complexity of which have resulted in a great depth of experience for the principal investigators and research staff at each Center.

We deliver engagement, expertise, and results.


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