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Our founders formed a close partnership for one simple reason: to cure as many patients with gene therapies as possible. This is our guiding principal. We work every day to bring as many customized 4D vectors into as many great products as possible, for as many diseases and patients as possible.

Many companies have benefited greatly from a leadership duo with complementary skill sets. In partnership, our founders are able to bring together deep expertise in bioengineering, vector discovery, virology, product design, product development, clinical trials, regulatory affairs, business development, management and entrepreneurship. Both have spent over 15 years in the gene therapy and viral vector therapeutics field, but they focused on different ends of the R&D spectrum. While Dr. Schaffer focused on basic scientific innovation and vector discovery technologies, Dr. Kirn had focused on product design, clinical R&D, biotech entrepreneurship and business development. Together, true synergy was possible.


David H. Kirn MD

Co-Founder, CEO & Co-Chairman

David Kirn is a biotechnology entrepreneur, physician-scientist and leader in therapeutic viral vector R&D. He is co-Founder, CEO & Chairman of 4D Molecular Therapeutics, and adjunct Professor of Bioengineering at UC Berkeley. He has co-founded and led four companies in the field. He is currently also Executive Chairman of Ignite Immunotherapy Inc, an oncolytic virus cancer vaccine company that he co-founded with Pfizer. In 2013 he was awarded the Johnson & Johnson Entrepreneur Innovator Award from the J&J Innovation Center.

Over the last 20 years, Dr. Kirn has been a leader in therapeutic viral vector and oncolytic virus cancer vaccine R&D. He led the design and development of over 10 therapeutic virus products for cancer oncolysis and/or immunotherapy, involving over 750 patients, including leading clinical trials from first-in-human studies to Phase 3 randomized trials. He was Founder & CEO of Jennerex, a pioneer in oncolytic immunotherapy for cancer, where he led the development of JX-594 (Pexa-Vec; engineered vaccinia virus) from concept into Phase 3. Pexa-Vec was the first armed oncolytic virus to demonstrate 1) intravenous (IV) tumor targeting and efficacy (Nature, 2011), and 2) a significant overall survival benefit in a randomized clinical trial (Nature Medicine 2013).

Through the consulting business that he founded, he led clinical development programs on therapeutic virus cancer immunotherapy products for Biogen and Novartis/Cell Genesys, and consulted in the field for Bayer, Novartis and Pfizer. At Onyx Pharmaceuticals, he was on the founding R&D team and he led the Onyx-015 oncolytic adenovirus program from concept to Phase 3. He co-authored papers reporting firsts for oncolytic viruses including 1) targeting of tumor suppressor-deficient cells (Science 1996, Nature Medicine 1997 and Nature Medicine 2000), 2) the first Phase 1-3 clinical trials with an engineered oncolytic virus, and 3) the first clinical trial demonstrating combination therapy efficacy (Nature Medicine 2000).

Dr. Kirn has held faculty positions at UCSF Medical School, the University of Oxford & UC Berkeley. He has co-authored over 100 publications, including publications in Nature, Nature Medicine, Nature Biotechnology, Science, Science Translational Medicine and others. He earned degrees from the University of California, Berkeley (BA; Departmental Citation as top graduate within the major; Phi Beta Kappa honor society); UCSF Medical School (Alpha Omega Alpha medical honor society); Harvard Medical School (Internal Medicine resident at Brigham & Women’s Hospital, Chief Medical Resident at WR-VA Hospital). He completed hematology-oncology and clinical research fellowships at UCSF, and a degree from Haas Business School at UC Berkeley.


David Schaffer, PhD

Co-Founder, Acting CSO & Co-Chairman

David Schaffer is a Professor of Chemical and Biomolecular Engineering, Bioengineering, and Neuroscience at University of California, Berkeley, where he also serves as the Director of the Berkeley Stem Cell Center. He graduated from Stanford University with a B.S. degree in Chemical Engineering, and from Massachusetts Institute of Technology with a Ph.D. in Chemical Engineering. He did a postdoctoral fellowship in the laboratory of Fred Gage at the Salk Institute for Biological Studies in La Jolla, CA. At UC Berkeley, Dr. Schaffer applies engineering principles to enhance stem cell and gene therapy approaches for neuroregeneration, work that includes novel approaches for molecular engineering and evolution of new viral vectors as well as new technologies to investigate and control stem cell fate decisions.

Awards: David Schaffer has received an NSF CAREER Award, Office of Naval Research Young Investigator Award, Whitaker Foundation Young Investigator Award, and was named a Technology Review Top 100 Innovator. He was also awarded the Biomedical Engineering Society Rita Shaffer Young Investigator Award in 2000, the American Chemical Society BIOT Division Young Investigator Award in 2006, the American Chemical Society Marvin Johnson Award in 2016, and was inducted into the College of Fellows of the American Institute of Medical and Biological Engineering in 2010.

Publications, Editorial & Scientific Advisory Boards:  Dr. Schaffer has over 180 scientific publications, has served on 7 journal editorial boards and 7 industrial scientific advisory boards, and is currently the Secretary and a Board of Directors member of the American Society for Gene and Cell Therapy (the premiere gene therapy society). He serves on the Board of Directors for UniQure (QURE, NASDAQ).


Melissa Kotterman, PhD

Co-Founder, Director and Head of AAV Research

Dr. Kotterman has over 10 years of experience in virology, molecular biology and gene therapy vector discovery. She is currently a co-founder and Director of AAV Discovery Research at 4DMT where she oversees AAV vector discovery efforts for over 10 different tissues and therapeutic areas.ver

Melissa’s PhD research focused on using directed evolution to develop gene delivery vectors based on adeno-associated virus (AAV) as tools for use in both basic research and in therapeutic applications. Specifically, she developed AAV vectors to improve gene delivery to human embryonic stem cells and adult neural stem cells. In addition, she helped to discover novel AAV variants that resist neutralization by antibodies in human sera. Melissa has co-authored over 15 patents and publications relating to AAV gene delivery, including an AAV vector review article with Dr. David Schaffer in Nature Reviews Genetics in 2014.

Melissa received her BS in Chemical Engineering and Biomedical Engineering from Carnegie Mellon University in Pittsburgh, Pennsylvania and her PhD in Chemical and Biomolecular Engineering from the University of California, Berkeley, where she was a National Science Foundation Graduate Research Fellow.


Theresa Janke

Co-Founder, Senior Vice President, Program & Alliance Management

Theresa Janke has over 15 years of experience in the biopharmaceutical industry, including clinical research and operations, alliance and program management, and business operations. She’s worked in diverse fields including immunotherapy, gene therapy, oncolytic virus therapy, and medical devices. She was a founding member of the management team at 4DMT, and is co-founder and board member of IGNITE Immunotherapy.

Theresa started her career in clinical research in medical devices with Allergan and Abbott. She later expanded into oncology therapeutics R&D, serving as Clinical Project Manager and Director of Clinical Operations at Jennerex Biotherapeutics, a pioneer in intravenous oncolytic virus immunotherapy. There she directed and conducted execution of clinical trials with Pexa-Vec (JX594, an engineered oncolytic vaccinia virus), including the first randomized Phase 2 oncolytic immunotherapy trial to show a statistically significant survival benefit (published in Nature Medicine, 2013). At Jennerex, she managed all aspects of study start-up: RFP process/CRO and specialty lab selection, protocol design/development, development of trial timelines and budgets, forecasting of clinical and non-clinical supplies, and development of trial plans, site selection, clinical site team training, and management, vendor selection and management, risk assessment and mitigation, managing internal and vendor timelines and budgets, collecting and analyzing performance metrics, compilation, analyses and reporting of clinical and safety data.

Theresa has directed multiple international partner alliances and has experience as a multi-national trial leader in the US, Canada, South Korea, Taiwan, China, Germany and France.

At Celgene, as Director of Clinical R&D Strategy and Alliances, Theresa worked closely with the SVP of Clinical R&D for hematology-oncology; she led the development of Clinical Research and Development (CR&D)-Regulatory 5-year integrated Clinical Development Plans (CDP) for each disease area within the hematology-oncology group.

Theresa graduated from the University of California, Santa Barbara in 1996 with a Bachelor of Science in Biopsychology. She also holds professional certificates from UC Berkeley in the area of clinical project management.

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