Perry Karsen

Venture Partner

Perry Karsen joined Third Rock Ventures as a venture partner in 2016. He is a recognized leader in the development and growth of successful, product-driven biopharmaceutical companies. 

  • Board member of Jounce Therapeutics
  • Board member of Nurix
  • Board member of Pliant Therapeutics
  • Board member of Voyager Therapeutics

Previously, Perry was the chief executive officer of Celgene Cellular Therapeutics from May, 2013 until his retirement from Celgene Corporation at the end of 2015. He held the position of executive vice president and chief operations officer at Celgene Corporation from July 2010 to May 2013 and he served as senior vice president and head of worldwide business development at Celgene and president of the Asia/Pacific Region, from May 2004 until February 2009. Perry was the president and CEO of Pearl Therapeutics, a privately held biotechnology company subsequently acquired by Astra-Zeneca, from February 2009 until July 2010. Earlier in his career, Perry held executive positions at Human Genome Sciences, Bristol-Myers Squibb, Genentech and Abbott Laboratories. He also was a general partner at Pequot Ventures from 2000-2003 focusing on investments in biotechnology and medical devices. 

Perry has a B.S. in Biological Sciences from the University of Illinois, Urbana, an M.A. of Arts in Teaching Biology from Duke University, and a Masters of Management from the Kellogg School of Management at Northwestern University. Perry was appointed chairman of the board of directors for Intellia Therapeutics in 2016, and also serves on the boards of several privately and publicly held biotechnology companies, including OncoMed Pharmaceuticals and several Third Rock portfolio companies.  He is currently on the board of the Biotechnology Innovation Organization (BIO) and is a past member of the board of directors of the Alliance for Regenerative Medicine (ARM). Perry is also on the boards of The Gladstone Foundation and the Sonoma Land Trust.

Perry showed up in costume for his kindergarten Halloween party one day before the school Halloween celebration. 

Administrative Support

Marcia Hemphill
Office Manager-West Coast and Executive Assistant
(415) 766-3638

Associated Portfolio Companies


Alexis Borisy


Abbie Celniker, Ph.D.


Neil Exter


Kevin Gillis

Partner/Chief Financial Officer

Charles Homcy, M.D.


Sarah Larson

Partner/Chief Human Resources Officer

Mark Levin


Craig Muir

Partner/Chief Technology Officer

Cary Pfeffer, M.D.


Kevin Starr


Robert Tepper, M.D.


Venture Partners

Frank T. Gentile, Ph.D.

Venture Partner

Mark A. Goldsmith, M.D., Ph.D.

Venture Partner

Perry Karsen

Venture Partner

Christoph Lengauer, Ph.D.

Venture Partner

Philip Reilly, M.D., J.D.

Venture Partner

Stephen Sherwin, M.D.

Venture Partner

Barbara Weber, M.D.

Venture Partner


Keith Dionne


Jeffrey Finer, M.D., Ph.D.


Robert Kamen, Ph.D.


Glenn Pierce, M.D., Ph.D.


Jeffrey Tong, Ph.D.


Laurence Turka, M.D.


Domain Experts

Brian Albrecht, Ph.D.


Dina Ciarimboli

General Counsel

Cynthia Clayton

Head of Communications

Tim Funnell, DPhil.


John Keilty

General Manager, Platform Operations


Andrea DiMella

Recruiting Director

Tracy Nicholson

Recruiting Director

Chris Robinson

Vice President, Recruiting


Chelsea Place Johnson, Ph.D.

Senior Associate

Vyas Ramanan, Ph.D.



Zoe Angell

Executive Assistant

Megan Graziano

Manager of Operations and Administration

Linda Heath

Executive Assistant

Marcia Hemphill

Office Manager - West Coast and Executive Assistant

Rhea Kappa

Receptionist/Administrative Assistant

Laura Klein

Administrative Assistant

Maribel Laboy

Executive Assistant

Ian Miller

Administrative Assistant

Corey O’Keeffe

Event Planner & Communications

Tracy Williams

Executive Assistant

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