Our Medical Director, Cherian Verghese, M.D., is a physician-investigator who has extensive experience in neuropsychiatric studies across phases II-IV. After earning his medical degree in Bombay, India, he completed training in Psychiatry and Neurology, and received Board Certification in India, UK, and USA. He spent the early part of his career at the Medical College of Pennsylvania in academic psychiatry. He completed a Fellowship in Psychopharmacology Research, on the neuroendocrinology of polydipsia-hyponatremia in persons with schizophrenia. He served as Inpatient Director and Associate Chair of psychiatry at the Albert Einstein Medical Center in Philadelphia.

Organization History & Key Milestone Dates:

2003: Keystone Clinical Studies was founded by Cherian Verghese, MD, Medical Director and Principal Investigator, and his brother Thomas.

2009: Became a partner site with Quintiles (now IQVIA).

2005-2015: Therapeutic areas were Schizophrenia, Depression, Anxiety Disorders, ADHD.

2019: Stephen Litman, MD, Geriatrician joins as Sub-Investigator.

2021: Moved to new offices.




Why Was Keystone Founded?

Dr. Cherian Verghese is a physician-investigator, who has dedicated his career to developing new medications to treat neuropsychiatric disorders. After earning his medical degree in Bombay, India, he completed training in Psychiatry and Neurology, and received Board Certification in India, UK, and USA.

In 2003, he founded Keystone Clinical Studies (KCS) as an independent clinical trial site with his brother, Tom Verghese as co-founder, and continued to grow the site after Tom passed away in 2019. He has been the Principal Investigator on over 130 clinical trials to date and has been instrumental in the FDA approval of medications in over 10 different indications.

Who Does Keystone Serve?

Keystone serves the broader Philadelphia-Camden-Wilmington area where 23% of the population is over 60 and 39% of the population consists of minority communities. Pennsylvania is the 5th largest state by Alzheimer’s population – 280,000 people age 65+ are living with Alzheimer’s in the state and that number is expected to grow by 14% by 2025.

Keystone Clinical studies is now a part of Flourish Research.

Being a part of Flourish Research means Keystone can offer the community the best opportunities to participate in more trials that advance life-changing therapeutics.


Flourish sites are still managed by the local physicians, clinical and support staff that you have come to know and trust.

Our Mission & Vision

Advancing the health and wellness of society through clinical trials.

Our Core Values

We Respect and Care for ALL

  • We honor ourselves and others.
  • We celebrate a culture of belonging and recognition.

We Do the Right Thing

  • We are honest and ethical – even if it’s the hard thing to do.
  • We live diversity authentically and organically.

We Own Our Actions

  • We are accountable to our employees, our clients, and our community.
  • We are aligned in our thoughts, words, focus and actions.

We Are Collaborative and Have a Can-Do Attitude

  • We work together towards optimal solutions.
  • We have a positive and innovative approach.

We Have the Highest Standards

  • We are consistent and reliable with meticulous attention to detail.
  • We relentlessly pursue perfection.

Meet Our Leaders

Our most important asset is our people, and the
leadership team is proud to serve them.

Learn More