Our mission is to develop innovative, transformative therapies for patients with devastating diseases through novel genome editing
Caribou Biosciences is a clinical-stage CRISPR genome-editing biopharmaceutical company dedicated to developing transformative therapies for patients with devastating diseases. The company’s genome-editing platform, including its Cas12a chRDNA technology, enables superior precision to develop cell therapies that are armored to potentially improve activity against diseases. Caribou is advancing CB-010 and CB-011 as off-the-shelf CAR-T cell therapies that have the potential to provide broad access and rapid treatment for patients with hematologic malignancies.
Leadership team
Rachel Haurwitz, PhD
Rachel is a co-founder of Caribou Biosciences and has been its president and chief executive officer and a director since the company’s inception in 2011. Rachel is an inventor on patents and patent applications covering multiple CRISPR-based technologies, and has co-authored several scientific papers in high-impact journals characterizing CRISPR-Cas systems. In 2014, she was named by Forbes Magazine to the “30 Under 30” list in Science and Healthcare, and in 2016, Fortune Magazine named her to the “40 Under 40” list of the most influential young people in business. In 2018, the Association for Women in Science recognized Rachel with the annual Next Generation Award. She serves on the board of directors for Biotechnology Innovation Organization (BIO). Rachel earned an AB in biological sciences from Harvard College and a PhD in molecular and cell biology from the University of California, Berkeley
Tina Albertson, MD, PhD
Tina is the chief medical officer for Caribou Biosciences and is responsible for strategic leadership of the company’s clinical programs and the clinical, regulatory, and medical affairs functions. Tina brings 15 years of experience leading the development of cellular therapies and biologics. Previously, Tina was chief medical officer and head of development for Lyell Immunopharma, where she built and led the clinical development function and initiated two Phase 1 clinical trials evaluating CAR-T cell and TIL therapies in solid tumors. Prior to Lyell, she was vice president of global drug development at Juno Therapeutics, where she led the global development of BREYANZI (lisocabtagene maraleucel) from preclinical studies to the BLA filing that ultimately led to the initial FDA approval. She previously served as medical director of clinical development and experimental medicine at Seagen (formerly Seattle Genetics). Tina earned her MD from Stanford University and completed a clinical fellowship in pediatric hematology/oncology at Seattle Children’s Hospital and residency in pediatrics at Denver Children’s Hospital. She earned her PhD in cancer biology from the University of Washington and her BS in molecular biology from the University of Oregon.
Barbara McClung, JD
Barbara serves as chief legal officer and corporate secretary for Caribou Biosciences, where she oversees and manages all legal functions, including corporate and board governance, securities reporting, compliance, contracts and corporate transactions, employment law, and intellectual property strategy. Prior to joining Caribou in 2015, she was General Counsel and Corporate Secretary at Intarcia Therapeutics, Inc. and also at Cygnus, Inc. Barbara began her career as a patent attorney with E. I. du Pont de Nemours and Company, and then joined Chiron Corporation where she was patent counsel for Chiron’s vaccine division. Barbara is a member of the California, Delaware, and Pennsylvania state bars, and is a registered patent attorney before the United States Patent and Trademark Office. She received a BA from the University of California, San Diego, an MA from the University of Pennsylvania, and a JD from the University of Pennsylvania Law School.
Sri Ryali
Sri Ryali is the chief financial officer for Caribou Biosciences and is responsible for strategic leadership of the company’s corporate finance, accounting, and investor relations and corporate communications functions. Most recently, Sri served as the chief financial officer of Codexis, Inc., a publicly traded enzyme engineering company. Previously, he served as chief financial officer of Eiger BioPharmaceuticals, Inc., then a publicly traded, commercial-stage company. Previously at Aimmune Therapeutics, Inc., Sri held roles of increasing responsibility, most recently as vice president of finance. Earlier in his career, he worked at Onyx Pharmaceuticals, Inc. and Amgen Inc. in finance-related positions of increasing responsibility. Sri earned an MBA from the UCLA Anderson School of Management and a BA from the University of California, Los Angeles, with a double major in economics and microbiology, immunology, and molecular genetics.
Reigin Zawadzki
Reigin Zawadzki serves as chief people officer for Caribou Biosciences and is responsible for leading the company’s human resources and people strategy. Reigin brings more than 20 years of experience leading human resources in the biotechnology industry. She has a proven track record for creating talent and culture practices that result in positive employee experiences that enable people to thrive. She understands the significance of having a diverse and inclusive culture to attract and retain great people and drive corporate goals and results. Previously, Reigin was vice president and chief human resource officer for Theravance Biopharma, responsible for organizational design, training and development, talent acquisition, employee engagement, legal compliance, and total rewards. At Theravance, she served in roles of increasing responsibility, supporting the organization through multiple stages of growth. She began her career in recruiting at Heidrick & Struggles. Reigin earned a BS from the Ohio State University.
Justin Skoble, PhD
Justin serves as senior vice president of technical operations for Caribou Biosciences and is responsible for leading development, manufacturing, testing, release, and distribution of the company’s critical raw materials and investigational products. Justin brings over 20 years of development experience in the biotechnology sector with a focus on immuno-oncology. Prior to joining Caribou, he was chief development officer at Actym Therapeutics. His experience includes previous leadership roles at Aduro Biotech, Anza Therapeutics, and Cerus Corporation. Justin earned his undergraduate degree in biology from Vassar College, his PhD in molecular and cell biology from the University of California, Berkeley, and conducted his post-doctoral fellowship at the University of California, San Francisco.
Enrique (Kike) Zudaire, PhD
Kike serves as senior vice president of translational research for Caribou Biosciences and is responsible for advancing translational strategies across the company’s clinical portfolio. He previously led Caribou’s therapeutics discovery team, shaping the company’s scientific strategy and discovery capabilities across allogeneic CAR-T and iPSC-derived CAR-NK programs in oncology and autoimmune disease. Prior to joining Caribou, Kike was the head of cell therapy and immuno-oncology organizations in oncology translational research at Janssen R&D, where he advanced translational strategies across cell therapy and immuno-oncology programs, including CARVYKTI. He previously held a role as staff scientist at the National Cancer Institute, where his research focused on immuno-oncology, tumor angiogenesis, and the tumor microenvironment. Prior, he was an assistant professor at Autonomous University of Madrid. Kike received his BS in biology and PhD in cellular biology from the University of Navarra, Spain.
Andrew Guggenhime
Andrew Guggenhime, M.B.A., has served on our Board since April 2021. Mr. Guggenhime is President and Chief Financial Officer at Vaxcyte, Inc., a developer of vaccines, positions he has held since January 2021. He served as Chief Operating Officer and Chief Financial Officer of Vaxcyte from May 2020 to December 2020. Prior to joining Vaxcyte, he served as Chief Financial Officer of Dermira, Inc., a biopharmaceutical company, from April 2014 through the acquisition of the company by Eli Lilly and Company in February 2020. Prior to Dermira, Mr. Guggenhime served as Chief Financial Officer for CardioDx, Inc., a medical diagnostic company, from September 2011 to April 2014 and as a director of the company from April 2014 to July 2016. He also served as Chief Financial Officer for Calistoga Pharmaceuticals, Inc., a biopharmaceutical company, from September 2010 to April 2011, which was acquired by Gilead Sciences, Inc. in 2011, and as Chief Financial Officer for Facet Biotech Corporation, a biotechnology company, from December 2008 to June 2010, which was acquired by Abbott Laboratories in April 2010. Mr. Guggenhime previously served as Chief Financial Officer of PDL BioPharma, Inc., a biopharmaceutical company, until Facet Biotech was spun off from PDL BioPharma Inc. in December 2008. Prior to joining PDL BioPharma, Inc., he served as Chief Financial Officer for Neoforma, Inc., a provider of supply chain management solutions, which was acquired by Global Healthcare Exchange, LLC in March 2006. Mr. Guggenhime began his career in financial services at Merrill Lynch & Co. and Wells Fargo & Company. He serves as a member of the Board of Directors of Sling Therapeutics, a privately held biopharmaceutical company. Mr. Guggenhime received his B.A. in International Politics and Economics from Middlebury College and his M.B.A. from the J.L. Kellogg Graduate School of Management at Northwestern University.
Scott Braunstein, MD
Scott Braunstein, M.D., has served on our Board since June 2021. Since August 2015, Dr. Braunstein has served as an operating partner at Aisling Capital, an investment firm. He was Chairman of the Board and Chief Executive Officer of Marinus Pharmaceuticals, Inc., positions he held from November 2022 and September 2018, respectively, until Marinus was acquired by Immedica Pharma AB in March 2025. From July 2015 to March 2018, he was Chief Strategy Officer and Chief Operating Officer at Pacira Pharmaceuticals, Inc., a pharmaceutical company. Prior to Pacira, Dr. Braunstein spent 12 years from February 2002 to June 2014 with J.P. Morgan Asset Management as a healthcare analyst and managing director on the U.S. equity team and as portfolio manager of the J.P. Morgan Global Healthcare Fund. Dr. Braunstein serves on the Board of Directors of AtaiBeckley Inc. since May 2024, where he is Vice-Chairman of the Board, Lead Independent Director, Co-Chair of the Science and Technology Committee, and a member of the Audit Committee. Dr Braunstein also serves on the Boards of Directors of three privately held companies, Aegle Therapeutics, One Biosciences, and Ray Therapeutics, Inc. Dr. Braunstein began his career as a physician at the Summit Medical Group and as assistant clinical professor at Albert Einstein College of Medicine and Columbia University Medical Center. He received his B.S. in Biology from Cornell University and his M.D. from the Albert Einstein College of Medicine.
Rachel Haurwitz, PhD
Rachel Haurwitz, Ph.D., is a co-founder of Caribou, is our president and chief executive officer, and serves as a director of our company, positions she has held since our company’s inception in October 2011. Dr. Haurwitz is an inventor on patents and patent applications covering multiple CRISPR-based technologies and has co-authored several scientific papers characterizing CRISPR-Cas systems, including in Science. Since February 2020, she has served on the Board of Directors of the Biotechnology Innovation Organization (BIO). Dr. Haurwitz received her A.B. degree in Biological Sciences from Harvard College and her Ph.D. in Molecular and Cell Biology from the University of California, Berkeley, where she completed her thesis research in the laboratory of Dr. Jennifer A. Doudna.
David Johnson
David Johnson, M.B.A., has served on our Board since May 2022. Mr. Johnson is Chief Operating Officer of Vera Therapeutics, Inc. where he leads the product development and manufacturing, information technology, and facilities functions. Prior to joining Vera, he served as Chief Commercial Officer of Global Blood Therapeutics, Inc. (acquired by Pfizer, Inc. in October 2022), a position he held from March 2018 to December 2022, where he led the global commercial functions and facilitated the launch of Oxbryta® in 2019. Previously, Mr. Johnson was employed by Gilead Sciences, Inc. from 2003 to 2018, where he held roles of increasing responsibility in the company’s commercial organization, including as vice president, sales and marketing, Liver Disease Business Unit, where he was instrumental in building and leading Gilead’s liver disease franchise, including launching four medicines for hepatitis. Prior to that, Mr. Johnson led the Antiviral Business Unit at Gilead, where he helped launch and oversee the HIV franchise. Before Gilead, he had an 11-year tenure at GlaxoSmithKline plc, where he held various positions in sales, product marketing, business development, global commercial strategy, and portfolio development. Mr. Johnson received his B.A. in Business Marketing from the University of Puget Sound and his M.B.A. from the Kenan-Flagler Business School at the University of North Carolina.
Dara Richardson-Heron, MD
Dara Richardson-Heron, M.D., has served on our Board since November 2021. She is Chief Executive Officer of DRH Consulting, LLC, a management and executive consulting firm, a position she has held since August 2021. Dr. Richardson-Heron was Chief Patient Officer for Pfizer Inc., a biopharmaceutical company, from February 2020 to August 2021. Her previous executive leadership positions include Chief Engagement Officer and Scientific Executive for National Institutes of Health (March 2017 to January 2020); Chief Executive Officer of YWCA USA, Inc. (2012 to 2017); and Chief Executive Officer, Greater NYC Affiliate of Susan G. Komen for the Cure (2008 to 2012). Earlier in her career, she served as Assistant Executive Director/National Chief Medical Officer with United Cerebral Palsy of NYC/UCP Association and Executive Medical Director and Special Assistant to the Chairman and Chief Executive Officer at Consolidated Edison Company of New York, Inc. Dr. Richardson-Heron serves on the Board of Directors of The Hastings Center for Bioethics. She holds a B.A. in Biology from Barnard College and an M.D. from New York University School of Medicine.
Natalie Sacks, MD
Natalie Sacks, M.D., has served on our Board since May 2018. Dr. Sacks is an oncologist and is a Partner at Novo Holdings Ventures Investment since December 2022. Previously, she was Chief Medical Officer at Harpoon Therapeutics, Inc. (acquired by Merck & Co., Inc.) from October 2018 to June 2022. Prior to joining Harpoon, Dr. Sacks held various development leadership roles at multiple companies including Onyx Pharmaceuticals, Inc., a pharmaceutical company (acquired by Amgen, Inc.), from April 2011 to February 2014; Aduro Biotech, Inc., a clinical stage biopharmaceutical company, from September 2016 to September 2018; Exelixis, Inc., a pharmaceutical company, from September 2009 to March 2011; and Cell Genesys, Inc., a biotechnology company, from November 2002 to April 2009. She has been responsible for all aspects of development, from IND through later-stage development. From October 2004 to October 2016, Dr. Sacks held a faculty appointment at the University of California, San Francisco, where she was a volunteer assistant clinical professor of medicine in the Division of Hematology/Oncology. Dr. Sacks serves on the Board of Directors of three privately held companies, Clasp Therapeutics, Reunion Neuroscience, Inc., and Rondo Therapeutics. Dr. Sacks received her B.A. in Mathematics from Bryn Mawr College, her M.S. in Biostatistics from Harvard University School of Public Health, and her M.D. from the University of Pennsylvania School of Medicine.
Nancy Whiting, PharmD
Nancy Whiting, Pharm.D., has served on our Board since August 2021. Dr. Whiting is President and Chief Executive Officer and a member of the Board of Directors at Recludix Pharma, Inc., a biotechnology company, positions she has held since September 2021. She spent almost 15 years (from 2007 to 2021) with Seagen, Inc. (formerly Seattle Genetics), a biotechnology company, where she most recently served as Executive Vice President of Corporate Strategy. Dr. Whiting previously served as Executive Vice President of Late-Stage Development, Senior Vice President of Clinical Development and Medical Affairs, and Head of Experimental Medicine at Seagen. Dr. Whiting serves on the Board of Directors of Boundless Bio, Inc. since October 2023, where she is a member of the Nominating and Corporate Governance Committee. Dr. Whiting is Chair-Elect of Biocom California. Prior to Dr. Whiting’s tenure in the biopharmaceutical industry, she had a career in clinical pharmacy serving as a Clinical Oncology Pharmacist at Seattle Cancer Care Alliance, and previously as the Staff Pharmacist for the Bone Marrow Transplant and Acute Leukemia department at Vancouver Hospital. Dr. Whiting received her B.S. in Pharmacy from the University of British Columbia and received her Pharm.D. degree from the University of Washington.
Ran Zheng
Ran Zheng, M.S., has served on our Board since September 2021. From March 2021 to March 2025, Ms. Zheng was Chief Executive Officer of Landmark Bio, LLC, a public benefit limited liability company formed to advance the development of transformative new medicines. She remained Chief Executive Officer of Landmark Bio after the company’s merger with Artis BioSolutions until January 2026. She was Chief Technical Officer at Orchard Therapeutics, a commercial-stage global gene therapy company, from March 2019 to February 2021 and, in that role, she led the technical operations organization and helped advance the company’s product pipeline. Ms. Zheng has also held leadership positions at multiple biotechnology companies, including Amgen Inc., a biopharmaceutical company, from 2003 to 2010, and Genzyme Corporation, a biotechnology company (now Sanofi), from 1996 to 2000. She is on the Board of Directors for the Alliance for Regenerative Medicine. Ms. Zheng holds a B.S. in Biology from Beijing Forestry University and received an M.S. in Microbial Engineering from the University of Minnesota.
