Our Vision

To build a future where the body’s natural healing abilities
are supercharged to improve the quality and length of life.

To battle and treat multiple inflammatory diseases and ailments through the use of stemXcell activated stem cell therapies.

We are a team of dedicated scientists, clinicians, technologists and business professionals who are passionate about saving lives. Backed by twenty years of foundational stem cell research, PrimeGen US is engaged in the translation of novel cell therapy discoveries into clinical solutions. We are leading the fight against acute and chronic inflammatory diseases with our patented stemXcell™︎ platform.

stemXcell™︎ is the platform through which we discover, test and develop activated mesenchymal stem cells that are pre-programmed to treat targeted inflammatory diseases.

Today, we are preparing for FDA-authorized clinical trials that will test our stemXcell™︎ MSC treatments with enhanced immunomodulatory properties for treating chronic and acute liver diseases. Additionally, we are pursuing preclinical and clinical studies for other disease models, including NASH and ASH, and are continuing our research into numerous other inflammatory diseases.


PrimeGen US

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


Gallant Acquires VetCell USA IP

  • Gallant acquired VetCell FCGS IP
  • PrimeGen sharpens focus on stemXcell platform
  • PrimeGen expands clinical models for FDA review

Management Team

Mr. Tom Yuen

Mr. Tom Yuen

Chairman of the Board, Founder

After decades in the computer and electronics industries, and as a founder of publicly traded companies such as the Fortune 500 computer company AST Research Inc. in the 1980s and 90s and consumer audio giant SRS Labs, Inc. in the early 1990s through the early 2010s, in the early 2000’s Thomas Yuen, a successful serial entrepreneur, embarked on a personal battle with his chronic kidney disease, beginning 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 to improve the 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
    • UC Irvine 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

Mr. Jim McNiel

Chief Executive Officer, PrimeGen US

Mr. McNiel is a seasoned senior executive with more than 30 years of experience in high technology and private equity. He began his career as a software engineer for Lucasfilm Ltd. And later left engineering to enter marketing and product management at AST Research/Computer. After rising to the role of senior director of advanced products at AST Mr. McNiel moved to New York to start Cheyenne Software. Seven years later Cheyenne was sold to Computer Associates for $1.3 billion in cash. Mr. McNiel then joined Pequot Capital and served as a General Partner and led the firm’s software investment practice for nine years. Working on both coasts Mr. McNiel made investments in Netgear, Netegrity and other successful technology firms.

Mr. McNiel has served as the Chief Marketing Officer for public company NETSCOUT and CEO for FalconStor and Fifth Generation Software. Mr. McNiel has served on more than 20 public and private boards and was a board member and trustee of the Foundation Fighting Blindness and the Clinical Research Institute. Mr. McNiel studied business at the Wharton School and Finance at MIT Sloane and has received multiple awards from FastCompany, Cannes Lions, AdWeek, OneCentre and others.

Mr. McNiel was the creator and executive producer for the critically acclaimed Werner Herzog documentary Lo and Behold: Reveries of the Connected World.

Jim McNiel
Dr. Raymond Tong

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, 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 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. Yu Fang Shi, Ph.D.

Chief Science Officer, Director

Dr. YuFang Shi is a world-renowned stem cell pioneer and immunologist. In 2020, Shi joined PrimeGen Global’s board of directors, and was appointed as the company’s chief science officer. Dr. Shi brings with him a truly unique understanding of stem cells reinforced by decades of innovation and breakthroughs in the scientific field that align with PrimeGen Global’s mission to find a cure for chronic liver disease and other inflammatory diseases.

Dr. Shi was recently elected to Academia Europaea, the pan-European Academy of Humanities, Letters, Law, and Sciences, in parallel to holding active roles at several major academic institutions including University of Rome Tor Vergata, Medical School of Kunming University of Science and Technology, and Soochow University Institutes for Translational Medicine. Additionally, he is Editor in Chief for Nature’s Cell Death & Disease, a peer-reviewed online journal in the field of translational cell death.

Beyond his vast professional experience, Dr. Shi is also highly decorated and was among the first to be inducted into the Chinese National “Innovative Talents” program, receiving the title of National Distinguished Expert, and has received an Award for Excellence in Translational Stem Cell Research by Chinese Society of Cell Biology, among others.

Dr. Yu Fang Shi
Steven D. Gershick

Steven D. Gershick, CPA CGMA

Chief Financial Officer, Director

Mr. 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 has 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.

Joel Marh

Director of Research and Manufacturing

Joel Marh has over 20 years of academic and industry experience leading research in mammalian and human developmental stem cell biology, somatic cell reprogramming, and gene-editing techniques in animals and cells. He is an inventor of Primegen’s Key Patents and has been an author of many publications in high-profile scientific journals. Currently, Joel is overseeing both the R&D and Production efforts for PrimeGen.

Prior to joining Primegen, he was the Director of the Mouse Transgenic Facility at the Institute for Biogenesis Research at the University of Hawaii. There he led a group developing novel genome editing tools, protein expression model system in stem cells and mammalian cells, and genetically modified mouse models used for translational research.  He has also previously held senior roles at Advanced Cell Technologies, developing and modifying patient-specific human embryonic stem cells for therapies.  Before that, he was a member of the mouse cloning team at the Institute for Biogenesis Research at the University of Hawaii.

Joel Marh
Steven D. Gershick


Director of Marketing

Mr Ramos is a scientist with over 20 years of expertise in combined R&D, process development, and scientific management in the biotechnology industry. Tom’s career has been focused on starting up and growing teams involved in biomanufacturing, product management and clinical trials. Tom has a strong technical foundation in Immunology, Stem Cell Biology, and Cell Therapy. Tom’s business management experience is in marketing, product development, scientific communications, business development, and intellectual property.


Tom has a B.S. and an M.S. in Immunology from Cal Poly Pomona; and an M.B.A. from the University of California, Irvine.  He has co-authored many publications and has presented his research at science-focused events. Tom has an entrepreneurial perspective in the biotech industry and specializes in growing scientific ideas to business success.
PrimeGen US

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