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Joseph Romanelli

President, Human Health International

Joseph Romanelli is president, Human Health International for Merck. He has P&L responsibility for Merck’s 75-plus markets outside of the U.S. and leads a team of 14,000 colleagues.  

From 2021 to mid-2022, Joseph served as chief executive officer of JiXing Pharmaceuticals, a China-based biopharmaceutical company.

Prior to JiXing, Joseph served in a variety of strategic and operational roles with increasing responsibility at Merck and Schering-Plough for 25 years. He led Merck’s business in China from 2016 through 2021. During his tenure in China, Merck became the second largest multi-national pharmaceutical company by revenue in the market, as well as the second largest subsidiary for the company globally. Joseph’s previous roles at Merck include serving as chief of staff to the president of Human Health and managing the Human Health business for multiple markets in Asia Pacific. In addition, he led the Investor Relations team at Merck.

Joseph received his undergraduate degree from the University of Delaware and his master’s in Business Administration from Fordham University’s Gabelli School of Management.

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Chirfi Guindo

Chief marketing officer, Human Health

Chirfi Guindo is chief marketing officer for Merck. He is responsible for leading the development and implementation of the company’s long-term strategy for the Human Health portfolio spanning oncology, vaccines, pharmaceutical and pipeline products.

Prior to this role, Chirfi was executive vice president and head of global product strategy and commercialization at Biogen. 

Before joining Biogen in 2017, Chirfi spent more than 25 years with Merck in positions of increasing responsibility in finance, sales, commercial and marketing. During his time with Merck, he led global marketing for Merck’s HIV portfolio, and also led the company’s Human Health businesses in Canada, the Netherlands and South Africa. Chirfi has been recognized for developing strong talent and forging innovative public-private partnerships that expand access to Merck medicines, while elevating the profile of Merck as a patient-focused company.

Chirfi is a graduate of Ecole Centrale de Paris (France) with a degree in engineering and has a master’s of Business Administration from New York University’s Stern School of Business.

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Douglas M. Baker, Jr.

Director since



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Mr. Baker has wide-ranging expertise in corporate governance and general and organizational management, including a deep understanding of global marketing, sales and operations of public companies. Mr. Baker is a Founding Partner of E2SG Partners, a company that invests in environmentally sustainable technologies. Previously, Mr. Baker was Chairman & Chief Executive Officer of Ecolab Inc., a provider of water and hygiene services and technologies for the food, hospitality, industrial and energy markets. Mr. Baker is also a member of the Board of Target Corporation and served as their Lead Independent Director from 2015 to 2021. This directorship along with his experience at Ecolab and his previous directorship at U.S. Bancorp provide him with deep experience on governance issues facing large public companies.

Career highlights

E2SG Partners

  • Founding Partner (2022-Present)

Ecolab Inc.

  • Executive Chairman (2021-2022)
  • Chairman and Chief Executive Officer (2006-2020)
  • Chief Executive Officer (2004-2006)
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Jannie Oosthuizen

President, Merck Human Health U.S.

Jannie Oosthuizen leads Merck Human Health U.S., which is Merck’s largest business globally. He is responsible for P&L, strategy, customer engagement and commercialization in the U.S. for Merck’s broad portfolio of human health medicines and vaccines.

Jannie joined the company in 2014 to lead the Human Health oncology business in Asia Pacific and Latin America, then led Merck’s business in Japan from 2016 to 2020, and then led Global Marketing for Oncology. In each of these roles, Jannie successfully created and implemented new strategies and innovative commercial models that delivered strong, leveraged growth and established Merck as a leading business in those markets and therapeutic areas.

Jannie has deep experience in a broad range of global markets and therapeutic areas, and in building and leading high-performing teams. Prior to Merck, Jannie spent 20 years at Eli Lilly in a wide range of commercial and marketing roles with increasing responsibility. He began his career with Eli Lilly in 1993 in his home country of South Africa. Jannie is a pharmacist by training and graduated from North-West University in South Africa. He has lived and worked in six countries spanning five continents with his wife and three children.

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Cristal N. Downing

Executive vice president and chief communications & public affairs officer

Cristal Downing joined Merck as executive vice president and chief communications & public affairs officer in 2021. In this role, Cristal leads Merck’s Corporate Affairs organization and is responsible for the development, advancement and execution of the company’s communications, public affairs, and Environmental, Social and Governance (ESG) efforts. Guided by business priorities and dedication to all who depend on the company’s lifesaving and life-changing work, Cristal is focused on fostering a deep understanding of Merck’s scientific contributions and impact on global health, ensuring public policy priorities stay aligned with business priorities, and enabling strategic engagement and impactful outcomes with a broad range of internal and external stakeholders.  

Most recently, Cristal was vice president, Communications & Public Affairs, Medical Devices, at Johnson & Johnson, where she fortified and amplified the strategy that conveys how the business is elevating the standard of patient care. Prior to that, she held the role of vice president, Global Finance Communications at Johnson & Johnson, where she partnered with the chief financial officer to implement communications and public affairs strategies that enabled the CFO and CEO strategic platforms.

Cristal also co-led the development and implementation of “Our Race to Health Equity” — Johnson & Johnson’s Racial & Social Justice strategy. She has more than 20 years of leadership expertise and capabilities, working in dynamic and complex organizations, including American Express, JP Morgan Chase, and Wells Fargo.

Cristal is a member of the board of trustees for the Ronald McDonald House of Central & Northern New Jersey and is affiliated with several key communications associations. Cristal received her bachelor of arts degree in communications from Monmouth University.

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Michael A. Klobuchar

Executive vice president and chief strategy officer

Mike Klobuchar serves as the chief strategy officer for Merck. He leads the advancement and execution of the company’s strategy, with additional responsibility for business development and information technology. Prior to this role, Mike was senior vice president and finance lead for Merck Research Laboratories, the company’s research and development organization, and led the Global Portfolio and Alliance Management group within the organization.

Previously, Mike was senior vice president, Corporate Strategy and Financial Planning, focused on developing and implementing improvements to the company’s operating model. He was also president, Merck Global Health Innovation Fund, and led key elements related to the integration of Merck Research Laboratories with Schering-Plough R&D following the merger of the two companies.

Mike joined Merck Research Laboratories in 1998 and has held a wide range of positions of increasing responsibility in the company’s finance, strategy, manufacturing and research organizations.

Mike received his MBA from Villanova University, a master of science degree in chemical engineering from Rutgers University and a bachelor of science degree from Purdue University.

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Caroline Litchfield

Executive vice president and chief financial officer

Caroline Litchfield is executive vice president and chief financial officer for Merck, responsible for the company’s finance, procurement and real estate operations. 

Prior to this role, Caroline served as the company’s treasurer, a position that included responsibility for treasury, tax and investor relations. From 2014 to 2018, Caroline led finance for Human Health, the company’s largest business, overseeing financial operations and reporting in approximately 100 markets.

Previously, Caroline was the vice president and finance lead for the company’s Emerging Markets region when it was established in 2009 following the merger of Merck and Schering-Plough and was instrumental in integrating the two companies. She joined Merck in 1990 in its U.K. business and has held a wide range of positions of increasing responsibility in the company’s country, regional and global finance functions.

Caroline received her Bachelor of Science degree in Mathematics from the University of Leicester and is a fellow of the Chartered Institute of Management Accountants.

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Stephen L. Mayo, Ph.D.

Director since


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Dr. Mayo has extensive scientific experience relevant to the biopharmaceutical industry, including being the Bren Professor of Biology and Chemistry, Merkin Institute Professor and former Chair of the Division of Biology and Biological Engineering at the California Institute of Technology (“Caltech”) and co-founder of Xencor, a public antibody engineering company. In addition, in his role as the former Vice Provost at Caltech, Dr. Mayo oversaw Caltech’s technology licensing program. Elected to the National Academy of Sciences in 2004 for his pioneering contributions in the field of protein design, Dr. Mayo has also served as a presidential appointee on the National Science Foundation’s National Science Board and as an elected board member for the American Association for the Advancement of Science. Dr. Mayo also serves as a member of the board of directors of Sarepta Therapeutics, Inc and Allogene Therapeutics, Inc.

Career highlights

California Institute of Technology

  • Merkin Institute Professor (2021-present)
  • Bren Professor of Biology and Chemistry (2007–present)
  • Chair, Division of Biology and Biological Engineering (2010–2020)
  • Vice Provost for Research (2007–2010)

Howard Hughes Medical Institute, non-profit medical research organization

  • Investigator (1994–2007)
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Dean Y. Li, M.D., Ph.D.

Executive vice president and president, Merck Research Laboratories

Dean Li serves as executive vice president and president of Merck Research Laboratories. He leads the company’s worldwide human vaccines and therapeutics research and development organization.

Since joining Merck in 2017, Li has held leadership roles in the translational medicine and discovery functions and was appointed to president, Merck Research Laboratories in January 2021.

Prior to joining Merck, Li held positions of increasing responsibility in translational medical research at the University of Utah. Most recently he served as the H.A. & Edna Benning Professor of Medicine and Cardiology, chief scientific officer, associate vice president and vice dean at the University of Utah Health System. From 2015 to 2016, he also served as interim CEO of Associated Regional University Pathologists, one of the United States’ largest clinical reference laboratories. During his tenure at the University of Utah, he co-founded several biotechnology companies based upon research conducted in his laboratory, including Recursion Pharmaceuticals, Hydra Biosciences and Navigen Pharmaceuticals.    

Li received his Bachelor’s degree in chemistry from the University of Chicago and his graduate and clinical training at Washington University School of Medicine in St. Louis. Li is a board-certified cardiologist, a member of the American Society for Clinical Investigation and the Association of American Physicians.

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Dave Williams

Executive vice president, chief information & digital officer

Dave Williams is Merck’s chief information and digital officer. Under his direction the technology organization is focused on helping Merck’s research, manufacturing and business units develop and leverage digital solutions to serve customers and achieve business value. 

Previously, Dave was chief information officer of Merck Animal Health. There he led the development and execution of a digital transformation that deployed several cloud-based platforms and capabilities, resulting in streamlined operations and improved customer engagement. 

Prior to that, Dave founded Merck Animal Health Ventures, which brings together capabilities across veterinarians, start-ups, inventors, entrepreneurs, customers and investment partners to develop new solutions that address unmet customer needs. He also led Sure Petcare, a companion-animal portfolio of digital services and solutions within Merck Animal Health, where he had profit-and-loss responsibility. 

Earlier in his career, Dave was executive director of enterprise information management at Merck and held several IT leadership roles at Schering-Plough.

Dave currently serves on the board of the National Center for Women in Technology and is a member of the Osage Partners Advisory Council. 

He holds a bachelor of science in economics and finance from the University of Scranton.