Our Mission:

To deliver on the promise of cellular treatments through proprietary and patented technologies that target and influence the inflammatory process…

…the root of most diseases.

A Note From Our Chairman


During the winter of 1980 my kidneys failed, and I was informed that I would require dialysis for the rest of my life.  I also learned that my condition was hereditary, and that my children could face similar issues in their future.  This dire outlook inspired me to make it my life’s work to identify new therapies for the disease, as well as a broad array of other chronic diseases.  After many years of research and reaching out to numerous experts on possible treatments, I learned of stem cells and their exciting potential.

In 2002, the PrimeGen story began.  From its inception, PrimeGen has been at the forefront of numerous cell therapy breakthroughs, and led in pioneering roles in many of the exciting cell therapy applications either in use or being explored today, including adult reprogramming of adult multipotent stem cells, fertility preservation, the derivation and use of iPSCs, MSCs, and more.

At PrimeGen, we continue to maintain a leadership role in the cellular therapy industry and are working diligently toward our vision of making cell therapies a viable treatment for countless diseases in the years ahead. We are committed to building on our performance in areas where we are strong, while persevering in other areas where we see opportunities for improving patient outcomes.


Tom Yuen

Developing Therapies for Which There Are No Cures

Born of the goal of creating life-changing treatments based on the immunomodulatory benefits of stem cells, PrimeGen is turning its goal into reality as we prepare our Primed-Cell™ platform for clinical trials in the USA and China


Since our founding in 2002, we’ve grown from a small R&D operation in Southern California to a multinational clinical cell treatment provider with a robust pipeline of products targeting several inflammatory diseases.

Based on a foundation of research spanning two decades and reinforced by numerous proprietary processes and patented technologies, our Primed-Cell platform focuses our therapies on treating inflammation, the root of most diseases, giving PrimeGen Global a distinct advantage over other cell therapy companies. Starting with potent, high-quality stem cells developed in line with the United States Food and Drug Administration’s GMP guidelines, we apply our patented techniques to jumpstart the immunomodulatory properties of our cells prior to patient administration. This process allows us to focus the cells on serving a specific function in the treatment of different disease types.

Today, we’re in the process of preparing our Primed-Cell allogenic MSC treatments for clinical trials in the USA and in China, where they will be used to treat human liver cirrhosis. We are also working on creating cell therapies based on our Primed-Cell platform for acute and chronic lung, kidney and heart disease models.

With a long history of innovation and stem cell industry firsts, our scalable and flexible Primed-Cell treatment platform and growing manufacturing and clinical capabilities, PrimeGen Global is positioned to make cell therapies a mainstay of modern medicine.

A History of Innovation


PrimeGen’s Story Begins!

PrimeGen’s Story Begins!

  • Starts cell therapy development using adult stem cells


PrimeGen Expands Human Research and Development

  • Focus expands to include immune-evasive MSCs
  • Develops human adipose MSC platform
  • Creates patented stem cell wound healing therapy
  • Starts Parkinson’s Disease neural stem cell R&D
  • Develops platform for making adult pluripotent stem cells


PrimeGen Makes History

  • Creates non-embryonic pluripotent stem cells (PSCs)
  • Turned PSCs into beating cardiomyocytes
  • Creates human heart, brain, bone and cartilage cells
  • Partners with RTI to develop orthopedic cell therapies


Sparks Legislators’ Interest in Cell Therapy

  • Presents research at landmark Capitol Hill briefing
  • Pioneers non-viral iPSC cell reprogramming
  • Studies BMSCs ability to restore spinal cord function


PrimeGen Creates Fertility Preservation Platform

  • Creates platform to preserve cancer patient fertility
  • Receives licensing approval from state of California for cell manufacturing facility
  • Increases focus on treating inflammatory diseases


PrimeGen Focuses on MSC Applications

  • Begins allogenic MSC preclinical work for cirrhosis
  • Commences research on human kidney applications


Develops Veterinary Cell Therapy Models

  • Starts MSC therapy development for pets
  • Opens ISO-7 certified facility in California


PrimeGen Introduces VetCell Therapeutics

  • Launches VetCell brand to market therapies for pets


Completes Human Cirrhosis Preclinical Study

  • Concludes 5 year preclinical study of cirrhosis patients
  • Embarks on FDA approval process for veterinary therapies
  • FDA grants PrimeGen INADs for canine AD
  • Starts clinical trial for treating canine OA with MSCs in Asia
  • Initiates canine AD study with Western University


PrimeGen Expands Global Presence

  • FDA grants PrimeGen INAD for FCGS
  • VetCell begins commercialization in Asia


Prepares for Human Clinical Trials

  • Prepares MSC clinical trial for liver cirrhosis in China
  • Initiates preclinical liver MSC study with USC
  • Initiates recruitment for FCGS clinical trial at UC Davis


Entering Clinical Phases

  • Initiates primed MSC clinical trial for liver cirrhosis in China
  • Concludes human MSC liver study with USC
  • Begins larger animal liver study with USC
  • Expands integration of multimodal MSC treatments
  • Initiates multi-center clinical trial for FCGS

Executive Team

Tom Yuen

Tom Yuen

Chairman of the Board, Founder

After decades in the computer and electronics industries, and founded publicly traded companies, such as Fortune 500 AST Research Inc. and audio giant SRS Labs, Inc. in the U.S., Thomas Yuen, a successful serial entrepreneur, embarked on a personal battle with his chronic kidney disease with his long tenure in the exploration and research of stem cells in human therapeutic applications.

PrimeGen Biotech was established in 2002 in Irvine, California, with the aim to advance the domain of stem cell research and applications towards the improvement of quality of life for people suffering from chronic or debilitating diseases.


1986 to present | UC Irvine, California, USA

Distinguished Alumnus Award
Outstanding Engineering Alumni Award
UC Irvine Medal
Extraordinarius Award
UC Irvine Foundation Board of Trustees
UC Irvine Institute for Innovation Founding Board

1991 | Beijing, China – Honorary Minzu University professor
2012 | TechAmerica, Orange County, California – Lifetime Achievement Award
2015 | Providence Speech & Hearing Center, Orange County, California – Board member

Dr. Raymond Tong M.D., Ph.D, MBA

Dr. Raymond Tong M.D., Ph.D, MBA

Chief Executive Officer, Director

Dr. Tong is a medical professional turned seasoned entrepreneur with over 30 years of experience in the healthcare industry across Asia and North America.  After founding a successful chain of twelve medical clinics in Toronto with annual revenues of USD 10 million, Dr. Tong returned to Hong Kong in 1988, and spent over ten years in senior management roles with multinational companies in the medical and pharmaceutical industries in Hong Kong and China. 

Dr. Tong then joined CITIC Pacific Limited in Hong Kong for over nine years, and was actively involved with all of the Group’s investment projects in the healthcare sector.

In 2009, Dr Tong established his personal investment and consultancy business in the healthcare and manufacturing industries in the Greater China region.

Dr. Shi Yu Fang, Ph.D.

Dr. Shi Yu Fang, Ph.D.

Chief Science Officer, Director

Trained as an immunologist, Dr. Shi decided to explore the world of stem cells 15 years ago. Dr. Shi obtained his Veterinarian Degree from China and then went to Canada for his M.Sc., Ph.D. and postdoctoral training in immunology. He moved to USA and first worked on T cell apoptosis and then focused on stem cells development. His recent most important discovery is the immune-modulatory nature of stem cells, which is now considered as one of the major functions of stem cells. He was also one of the first to use cytokines activation as a method to enhance the immunomodulatory effects of stem cells.

Dr. Shi relocated to China in 2008 and since then continue his contributions to the mainstream stem cell research field.

Dr. Leonard Makowka M.D., Ph.D., FRCS(C), FACS

Dr. Leonard Makowka M.D., Ph.D., FRCS(C), FACS

Chief Medical Officer, Human Solutions, Director

Over the past 30 years, Dr. Makowka has transitioned himself from a distinguished clinical and transplantation surgeon and medical researcher to a successful entrepreneur, advisor and board member.  Since obtaining his M.D. and Ph.D. from the University of Toronto respectively in 1977 and 1982, he has published over 400 articles and chapters in both clinical and basic scientific research.

Dr Makowka has served as chairman of the Department of Surgery and director of transplantation services at Cedars Sinai Medical Center in Los Angeles, professor of surgery at UCLA School of Medicine, and executive director of the Comprehensive Liver Disease Center at St. Vincent’s Medical Center in Los Angeles.  He is currently the chairman of the corporate advisory board of UCLA School of Nursing.

Upon his retirement from active practice of medicine, Dr. Makowka has established a reputable advisory consultancy in business investments and strategies in the healthcare, life sciences, and financial sectors, as well as serving on the board of several private and publicly traded companies.

Dr. Wang Ying M.D., Ph.D.

Dr. Wang Ying M.D., Ph.D.

Principal Investigator

Upon completion of her qualification as a Medical Doctor, Dr. Wang proceeded to specialize in the field of Immunology and attended her post-doctorate degree with the Institute of Physiological Chemistry and Pathobiochemistry at the University of Muenster in Germany.  She returned to China in 2011 and began to work at the Chinese Academy of Science in Shanghai, where she was later appointed as a full professor.  Her career centered in the detailed pathways of how stem cells communicate in the microenvironment.  Since 2013, Dr Wang has gained extensive clinical experience in clinical trial work with liver cirrhosis in China.
Mr. Wai Szeto

Mr. Wai Szeto

Chief Operating Officer, Executive Vice President, Director

Mr. Wai Szeto is an accomplished business development strategist, who is well versed in the formation of U.S. and international joint ventures.  Together with his strong experience in the development of global supply chains and manufacturing facilities, Mr. Szeto has assisted some of the largest companies in the world to generate billions in revenues.

Prior to becoming COO of PrimeGen, Mr. Szeto held senior management roles with the China and technology subsidiaries of Kingston, U.S., the largest chip manufacturer and provider in the world.  Before Kingston, Mr. Szeto served with Mr. Tom Yuen, as Vice President of Global Operations of AST Research, a Fortune 500 company and one of the world’s leading, personal computer manufacturers at the time.  He managed engineering groups that created leading-edge personal computers, developed global manufacturing and supply chain networks, cultivated strategic supplier relationships, and oversaw Asia Pacific marketing and sales.

Mr. Steve Gershick, CPA, CGMA

Mr. Steve Gershick, CPA, CGMA

Chief Financial Officer, Director

Steve Gershick has substantial, hands-on experience in operations, business planning and corporate finance, debt and equity-based seed, venture, institutional, and PIPE financing.  Interfacing between the various levels of the investment community in the U.S. with both private and public companies, Mr. Gershick is well versed in strategic alliance formation and management, mergers & acquisitions, and global technology licensing.

After graduating in Business Administration from California State University in 1977, Mr. Gershick obtained his Certified Public Accountant and Chartered Global Management Accountant accreditations.  He joined PrimeGen as COO/CFO from 2004-2008, and had been a member of the Board of Managers and Chief Financial Officer since 2014.

Mr. Gershick has also served as CFO and COO for several private and public companies in technology, biotechnology and life sciences, including NuRX Pharmaceuticals, a clinical stage biopharmaceutical company, and led the health services diligence and finance teams for a boutique merchant banking firm, including a USD$100 million Special Purpose Acquisition Company funded by Citigroup.