David J Kim

David brings a unique set of professional and academic credentials to his role as Managing Director of DigiTx. David has deep experience across the healthcare, technology and investment fields – first as a clinician at a major HMO network, followed by a successful stint as COO at a growth stage company. In addition, David has two decades of experience in the investment sector, including as Principal at MPM Capital and as Partner at Pinnacle Ventures. David has been a director or a board observer of multiple medical device and biotech companies. Moreover, David is working with multiple academic accelerators and translational medicine programs including the Catalyst Program within the UCSF Clinical & Translational Science Institute and U. of Michigan MTRAC program. Currently, David serves as a board member of Embr Labs, NeoSensory, Siris Medical, Tissue Analytics, and WellDoc.

David completed his internal medicine residency at Harbor-UCLA Medical Center and later served as Director of Urgent Care and Assistant Chief of Internal Medicine at Kaiser South San Francisco. David is a graduate of the Johns Hopkins University School of Medicine (M.D), Stanford Graduate School of Business (M.B.A.), and Pomona College (B.A., Biology). 

David is a frequent speaker at health technology and venture capital conferences.


miraj sanghvi

Miraj is a Principal at DigiTx Partners and brings a background with operational data science experience in the startup and healthcare industries. Before joining the firm, Miraj was a data scientist at multiple venture-backed startups in San Francisco, most recently as a Senior Data Scientist at VigLink. During his time there, he built machine learning models on terabytes of data in a production environment, while managing the data engineering platform. 

Miraj started his career as a Healthcare Policy Consultant working with the Centers for Medicare and Medicaid Services (CMS) on their Part D prescription drug program. His interest in healthcare spans multiple verticals, with additional experiences ranging from his work as a researcher at a microbiology lab, as an associate on a clinical trial, and as a research collaborator contributing on the development of a pediatric risk score. 

Miraj completed the Specialized Sciences Program at the University of Pennsylvania and holds a B.S. in Economics from Washington University in St. Louis. Miraj is a Board Member at Sensoplex and Board Observer at Siris Medical and Tissue Analytics.


Emre Karatas

Prior to joining DigiTx Partners, Emre was a consultant at Health Advances, a healthcare strategy consulting firm in San Francisco. At Health Advances, he advised clients in the biopharma, medical device, diagnostic, digital health, and health services spaces, performing due diligence, market assessment and forecasting, and corporate strategy development. Before Health Advances, Emre conducted research on the genetic and biologic influences of brain disorders at the University of Pennsylvania Center for Neurobiology and Behavior. He holds a B.A. in Biological Basis of Behavior from the University of Pennsylvania.


Dan Riskin
Venture Partner

Dan is an expert in healthcare artificial intelligence and a successful serial entrepreneur. Products he has developed and commercialized influence the care of millions of patients annually. His contributions in data-driven healthcare have been featured in Forbes, The Wall Street Journal, and other leading media. He served on the Obama Healthcare Policy Committee for the 2008 Presidential Campaign and testified before Congress on the 21st Century Cures Initiative.

He is also Founder and CEO of Verantos and previously held positions as Founder and CEO of Health Fidelity and as Special Projects Consultant at Apple. He is Adjunct Professor of Surgery and Adjunct Professor of Biomedical Informatics Research at Stanford University.

Dan is board-certified in four specialties, including surgery, critical care, palliative care, and clinical informatics. He holds degrees and fellowships from the University of California, Stanford University, and MIT.


Chihiro Hosoya, MSc, MBA
Venture Partner

Chihiro is a Venture Partner and BD / VC Head, Rx+ Business Accelerator, for Astellas Venture Management. In her role, Chihiro actively seeks opportunities in the growing field of Rx+ business, which would combine Astellas’ capabilities in pharma products with innovative healthcare technologies. Chihiro has 15 years of industry experiences in research and Business Development in addition to Rx+ business. She received an MSc from Waseda University and an MBA from Tsukuba University.


Sumiho Nakatsu, Ph.D

Sumiho is a Venture Partner and Associate Manager for Astellas Rx+ Business Accelerator. Sumiho joined the team in Sept. 2019 to pursue potential opportunities for innovative medical solutions in the Rx+ field. Rx+ is a healthcare solution moving beyond the prescription drug (Rx) business through which Astellas aims to create new revenue streams separately from our core Rx products, by combining Astellas’ capabilities with technologies from different fields. Prior to joining DigiTx, Sumiho contributed to strategic planning in the Rx+ Business Accelerator and operation of clinical trials in oncology at Astellas. She received her Ph.D. in virology from the University of Tokyo.


Makoto Ohmiya, Ph.D.

Since October 2018, Makoto has been a Venture Partner and Associate Investment Director, Rx+ Business Accelerator, for Astellas Venture Management. Makoto has more than 15 years of experience in Astellas, where he focused on Drug Discovery Research, specifically the CNS area. During his career as a neuroscience researcher, he acquired several patents and has contributed to new drug development. His focus now is digital technologies especially on solutions to address symptoms associated with CNS disorders.


Arnold Lee
REsearch analyst

Prior to joining DigiTx Partners, Arnold was a founding physician at One Medical Group. In his time there, he built unique digital experiences for patients across the country. Along with providing patient care, he consulted on in-house proprietary EMR development. Incidentally, he picked up an America’s Cup Championship along the way. Arnold moved into the world of data science in 2015 when he joined Lumiata. There he provided clinical expertise for machine learning models, working extensively with the ICD, CPT, SNOMED and RXCUI coding systems. He obtained Python certification at CCSF. Arnold completed his residency in internal medicine at Harlem Hospital (Columbia University Vagelos College of Physicians and Surgeons).