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Past, Present and Future Leaders

InterWest is proud and privileged to partner with visionary management teams who are shaping the future of Information Technology and Healthcare. The companies they have started are vital parts of the portfolio of industry-leading startups that InterWest has helped over the last four decades.

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InterWest Partners Mailing Address
548 Market St.
PMB 44661
San Francisco, CA 94104-5401
T: 650-854-8585
F: 650-854-4706

Early stage IT and Healthcare Investing

Arnie Oronsky


In Memoriam

"My years at InterWest have taught me that combining outstanding science with outstanding management is a formula for success—and that the greatest contribution I can make is to help life science entrepreneurs transform their ideas into profitable businesses with lasting value."

InterWest Team

Current Investments

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Arnie's bio

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Arnie's video

In Memoriam


It is with great sadness that we mark the passing of our friend and partner, Arnie Oronsky, in November 2020. 


Arnie had a truly remarkable career as an investor and managing partner at InterWest, and was a mentor and guiding light for many of us here. He joined InterWest in a full-time capacity in 1994, after serving as a special limited partner since 1989. 


Arnie brought a deep understanding of medical research to finding and investing in successful healthcare companies. He was instrumental in building companies that are focused on novel therapeutics in revolutionary areas of biology with the potential to replace current treatment paradigms.


He led InterWest’s Biotech/Pharma practice and was a board member of many of InterWest’s successful healthcare investments, including AkaRx, acquired by MGI Pharma (MOGN), Applied Genetic Technologies Corporation (AGTC), Aspreva Pharmaceuticals (ASPV), Centrexion Therapeutics, Coulter Pharmaceutical (CLTR), Corixa Corporation (CRXA), Dynavax Technologies (DVAX), EpicentRx, KalVista Pharmaceuticals (KALV), MacroGenics (MGNX), Myogen (MYOG), PMV Pharma (PMVP), Potenza Therapeutics, acquired by Astellas Pharmaceuticals, Salmedix, acquired by Cephalon (CEPH), Signal Pharmaceuticals, acquired by Celgene (CELG), Sera Prognostics, and TESARO (TSRO).


Prior to joining InterWest, Arnie was vice president for discovery research of the Lederle Laboratories division of American Cyanamid Company, where he directed research for new drugs.


Arnie also served as a Senior Lecturer in the Department of Medicine at Johns Hopkins School of Medicine and held a number of academic positions, including Assistant Professor in the Department of Medicine at Harvard Medical School and Adjunct Associate Professor in the Department of Orthopedics at Mount Sinai School of Medicine in New York City.



Arnie received a Ph.D. in immunology from Columbia University’s College of Physicians and Surgeons, and published more than 150 articles in scientific journals.


Arnie Oronsky

Information Technology