Our Team



Lead Scientific Officer

Founder, President, & CEO of Sierra Sciences

“I have spent almost my entire life trying to defeat the processes that cause us to age.

This has been a struggle of almost unimaginable proportions. And, now that we have finally, successfully developed a gene therapy that can do this we face a new struggle of how to fund the astronomical costs of gene therapy. My hopes now lie with Libella Gene Therapeutics to pull together the funding that is needed.

My mission in life is to turn old people into young people again. And, together with Libella we will do this.

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“Not all animals age, and most of those that do, do not do so by the same mechanisms that humans age. We are pretty unique. My research in this field has led me, 20+ years ago, to the belief that the kingpin of aging in humans is the shortening of our telomeres.

Since then hundreds, if not thousands, of scientific peer reviewed studies have confirmed this. And, some of these studies have even shown actual age reversal in every way imaginable, simply by lengthening the telomeres. No other theory on aging has ever done this! My last 20+ years of research has been devoted to finding ways to induce the telomerase gene in our cells to lengthen our telomeres and reverse our aging.”

Dr. Bill Andrews is the President and CEO of Sierra Sciences. As a scientist, athlete and executive, he continually pushes the envelope and challenges convention. He has been featured in Popular Science, The Today Show and numerous documentaries on the topic of life extension including, most recently, the movie The Immortalists in which he co-stars with Aubrey de Grey.

Since 1981, Bill Andrews has focused on finding ways to extend the human lifespan and healthspan through telomere maintenance. As one of the principal discoverers of both the RNA and protein components of human telomerase, Dr. Andrews was awarded 2nd place as “National Inventor of the Year” in 1997.

He earned his Ph.D. in Molecular and Population Genetics at the University of Georgia in 1981. He has served as Senior Scientist at Armos Corporation and Codon Corporation, Director of Molecular Biology at Berlex Biosciences and at Geron Corporation, and Director of Technology Development at EOS Biosciences. He is also a named inventor on over 50+ US issued patents on telomerase and author of numerous scientific research studies published in peer reviewed scientific journals.

Dr. Jeff Mathis, OTD, CHT

President, Libella Gene Therapeutics

Dr. Mathis formed Libella Gene Therapeutics in 2017. The sole goal of the new entity is to complete a human trial using AAV/hTERT to treat or significantly improve Alzheimer’s disease using telomerase gene therapy.

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Dr. Mathis attended K-State University, University of Kansas, and Kansas University Medical Center, receiving his undergraduate degree in Occupational Therapy in 1989. He then attended Creighton University and Rocky Mountain University of Health Professions, receiving his Clinical Doctorate of Occupational Therapy is 2005.

Dr. Mathis has been in private practice since 2003, which has grown into one of the largest multi-specialty healthcare practices in the mid-west, employing over 190 professional staff in two states. Two of his specialty facilities treat kids and young adults with physical disabilities and challenges with mental health. Both of these services are increasingly relying on genetic testing to guide and improve patient care. The early impact of genetic testing led Dr. Mathis to a strong interest in genetic therapies. It was the research and knowledge gained from interventions in current practices that led to a particular interest in the possible effects and benefits of the enzyme, telomerase.

Project Team

Dr. Sandra Kaufmann

Principle Investigator

Chief of Pediatric Anesthesia, Joe DiMaggio Children’s Hospital

Dr. Kaufmann’s avid interest in the science of anti-aging begun many years ago as an intense hobby. Utilizing her knowledge in cell biology, human pharmacology and physiology, this hobby has now become a main focus. The project represents years of non-clinical research leading to the first ever, comprehensive theory of aging.

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Dr. Sandra Kaufmann began her academic career in the field of cellular biology, earning a Master’s Degree from the University of Connecticut in Tropical Ecology and Plant Physiology. Turning to medicine, she received her medical Degree at the University of Maryland, and completed a residency and fellowship at Johns Hopkins in the field of pediatric anesthesiology. For the last five years she has been the Chief of Pediatric Anesthesia at the Joe DiMaggio Children’s Hospital, a nationally recognized center of excellence. Most recently, she was recognized as “Best in Medicine” by the American Health Council.

Dr. Joseph Raffaele


Co-Founder of PhysioAge Medical Group

Joseph Raffaele, M.D., is the co-founder of PhysioAge Medical Group, a clinical practice in New York City that is at the leading edge of the emerging field of medicine focused on scientifically sound approaches to staying younger longer.

As a clinician, researcher and educator in the subspecialty known as Age Management Medicine, Dr. Raffaele has for the past 15 years been helping advance innovative, evidence-based approaches to extending “healthspan”— keeping the body young and vital whatever its chronological age.

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Joseph Raffaele received his BA in philosophy from Princeton University and his MD from Hahnemann University Medical School in 1989. Dr. Raffaele did his residency at The New York Hospital/Cornell University Medical Center and was formerly a clinical assistant professor of medicine at Dartmouth Medical School while in practice at the Hitchcock Clinic. Dr. Raffaele is a member of the American College of Physicians, is board certified in internal medicine, and is a diplomat of the American Board of Age management Medicine.

In 1995 Dr. Raffaele began researching and developing a scientifically-based treatment program and co-founded PhysioAge Medical Group. Since 1997 Dr. Raffaele has been focused on age management medicine and biomarkers of aging. As CEO of PhysioAge, Dr. Raffaele developed the combination of biomarkers currently in use and has worked with Dr. Kumm to develop PhysioAge formula.

David W. Scott, Ph.D.

Project Team Member

Vice Chair of Research at USUHS

Dr. Scott has contributed to over 200 research papers on several subjects in immunology, focusing on immunologic tolerance, gene therapy, and most recently on engineering regulatory T cells for application in autoimmune diseases and hemophilia. He is the author of two textbooks, including a monograph entitled “The Nature of Immunologic Tolerance” and recipient of a numerous awards.

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David W. Scott, Ph.D. is Vice Chair for Research in the Department of Medicine at the Uniformed Services School of Health Sciences (USUHS) in Bethesda, MD. An alumnus of Antioch College, Dr. Scott received his M.S. degree from the University of Chicago and Ph.D. from Yale University in 1969. Following a post-doctoral fellowship at Oxford University, UK, he joined the faculty at Duke University in 1971, where he initiated his National Institute of Health-funded studies on immune tolerance mechanisms.

In 1983, he was named Dean’s Professor of Immunology at the University of Rochester, a post he held for 11 winters. Dr. Scott thereafter became Head of the newly formed Immunology Department at the Holland Lab of the American Red Cross, and moved to the University of Maryland School of Medicine in 2004. He assumed his current position at USUHS in September 2010.

Dr. Scott has contributed to over 200 research papers on several subjects in immunology, focusing on immunologic tolerance, gene therapy, and most recently on engineering regulatory T cells for application in autoimmune diseases and hemophilia. He is the author of two textbooks, including a monograph entitled, The Nature of Immunologic Tolerance, and recipient of a number of awards, including the Distinguished Service Award from the American Association of Immunologists (AAI, 2004), a Boerhaave Professorship at Leiden University Medical School, The Netherlands (2006) and the 2009 Scientific Achievement Award from the American Association of Pharmaceutical Scientists.

Active in science education, Dr. Scott has been Chair of Education Committees at the American Society for Microbiology and AAI. He has also served on the editorial boards of major immunologic journals, is Editor-in-chief of Cellular Immunology, and has been a member of National Multiple Sclerosis Society, Juvenile Diabetes Research Foundation and NIH Study Sections.

Dr. Haifeng Chen

Project Team Member, CEO at Virovek, Inc.

Dr. Chen is a senior bioscience professional / executive with extensive experience and solid knowledge on gene therapy, molecular biology, cell biology, immunology, and virology. It is his revolutionary technology that makes it possible to get telomerase into cells.

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Dr. Chen is the world’s foremost leader in the production of high quality, high production AAV. Dr. Chen attended Sun Yat-Sen University of Medical Sciences, University of Kansas Medical Center where is finished his post-doc training before launching ViroVek labs in 2006. Virovek is the only lab in the world that can produce large scale AAV of the quality and magnitude necessary to conduct our trial. He has been involved in the QC and small scale testing of our proprietary AAV production for the last year, and has been instrumental in being able to offer our revolutionary Phase 1 Human Trial.

Dr. Duk-Yong Shin

Project Team Member

Professor at the Dankook University College

Professor D.Y. Shin graduated from Pusan National University in 1983 and received his Ph.D. from the University of Tokyo, Japan in 1989. From 1989 to 1995, he was a doctoral researcher at the National Institute of Health (NIH) and the National Cancer Institute (NCI) . After returning to Korea in 1995, he became a senior researcher at the Korea Biotechnology Research Institute. He discovered the gene that suppresses senescence in 1997 and published it in the American Academy of Sciences. Since February 2000, he has been a professor at the Dankook University College of Medicine. In 2005, we discovered a new anticancer drug that only kills cancer cells that do not have the P53 gene and it was the most sensation biotechnology in its sector.

Dr. Yang Hu

Project Team Member, CSO at CD Genomics, INC.

Dr. Hu received this Ph.D. in 2013 from the University of Florida. He is now the Chief Scientific Officer in CD Genomics lnc. – the leading company focused on high throughput sequencing for 14 years. Dr. Yang Hu is an expert in genomics and transcriptomics, he has been working as the manager for hundreds of projects by using next- generation sequencing and microarray approaches, made a great contribution to academic and industrial discovery.

Cris Venner

Lead Project Manager, Clinical Research Specialist

Cris is based in Barranquilla, Colombia and is our lead project manager. She has a microbiology degree from Javeriana University – one of the top universities in Latin America. She also worked for Quintiles – the leading CRO in the world. Cris has a master’s degree on epidemiology from Universidad del Norte – the leading university in Colombia’s Caribbean coast. She was the research director at COFCA – one of the leading ophthalmology research centers in Colombia. Cris has worked in a number of study protocols that have been approved for trials and have successfully managed these trials.

Jorge Ulloa

Project Team Member

Chief of the Venous Disease Clinic

Dr. Ulloa is Chief of the Venous Disease Clinic at Fundación Santa Fe de Bogotá in Bogota, Colombia —one of the top healthcare institutions in Latin America. He is a professor at Universidad de los Andes in Colombia and an avid researcher on deep vein diseases treatment in collaboration with several American institutions. Dr. Ulloa was a fellow in vascular surgery at the Walter Reed Army Medical Center in Washington, D.C., a fellow in vascular surgery at the Military Hospital in Bethesda, MD, a fellow in biomolecular research from Harvard University in Boston, MA, and he was an intern at the Massachusetts General Hospital in Boston, MA.

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Dr. Ulloa has been awarded several prizes including the Centennial International Guest Scholar-Traveling Fellowship from the American College of Surgeons (2013); 1st Prize at the Colombian Society of Vascular Surgery (2001); 1st Prize in research at the International Union of Angiology in Ghent, Belgium (2000); and the Ben Eiseman Professorship in Surgery Award and Grant in Bethesda, MD (1997). Dr. Ulloa has delivered over 50 oral presentations, he has published over 15 papers, has authored four chapters and two books in his speciality, and co-invented and patented a venous pacemaker and electric stimulator to prevent the economic class syndrome.

Sierra Sciences

Laura Briggs

Project Team Member

Ph.D. VP of Research & Discovery

Laura Briggs received her B.S. degree in Nutrition in 1993 and her Ph.D. in Environmental Science and Health in 2000 from the University of Nevada, Reno. After a one-year post-doctoral position at UNR she joined Sierra Sciences in 2001.

In addition to coordinating research and development at Sierra Sciences, Dr. Briggs is also currently serving as the biology Lab Coordinator for Truckee Meadows Community College (TMCC) and has collaborated on research projects at the V.A. Medical Center in Reno, Nevada.

Lancer Brown

Project Team Member, VP of Research

Lancer received his B.S. and M.S. degrees in Biotechnology in 2003 from the University of Nevada, Reno. Lancer is an expert in designing and building plasmid DNA, developing high-throughput assays, screen compounds for telomerase activation, and optimize gene therapies to be used to treat aging-related diseases.

Kelly Colby

Project Team Member, Scientist

Kelly Colby has been working with Sierra Sciences since 2009.

Paul Ciotti

Project Team Member, Scientist

Paul Ciotti has been working with Sierra Sciences since 2009. Prior to that he has spent 19 years working in Biotech at Charles River, Inc. and Ashfield Healthcare.

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