Leadership | Avantor


Our leadership team has come from world-class companies and has extensive experience serving the life sciences, advanced technologies and applied materials space. The hallmark of the team is its ability to execute – and this is validated by the results we have delivered.


Michael Stubblefield

President and Chief Executive Officer

Michael Stubblefield is our President and CEO, a position he has held since May 2014. Prior to assuming his current position, he served as a Senior Expert for the Chemicals Practice of McKinsey & Company. Mr. Stubblefield also held various leadership roles with Dallas-based specialty materials and chemical company Celanese Corporation, including Vice President and General Manager, Advanced Engineered Materials and Chief Marketing Officer. He earned a bachelor’s degree in chemical engineering from the University of Utah, as well as an MBA from Texas A&M University-Corpus Christi.

Mr. Stubblefield serves on the Engineering National Advisory Council for the John and Marcia Price College of Engineering at the University of Utah. He is also a Trustee of the Committee for Economic Development, the public policy center of The Conference Board. In 2023, Mr. Stubblefield was recognized by the Philadelphia Business Journal as a “Most-Admired CEO.”

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R. Brent Jones

Executive Vice President and Chief Financial Officer

R. Brent Jones is our Executive Vice President and Chief Financial Officer. In this role, he oversees our Company’s accounting, financial business support, financial planning and analysis, treasury, investor relations, internal audit, and tax functions. Previously, he served as Executive Vice President, Chief Financial Officer and Chief Operating Officer at Lifescan, a global leader in blood glucose monitoring and digital health technology. Prior to LifeScan, Mr. Jones was CFO at Klöckner Pentaplast Group, a global provider of packaging products for the pharmaceutical, food and beverage and other consumer end markets. He was previously the interim CFO of Pall Corporation, where he led the company’s sale to Danaher for $13.8 billion in 2015. He spent the first 15 years of his career in investment banking with several firms including Merrill Lynch, Bank of America, and corporate law with Cravath, Swaine, & Moore. Mr. Jones holds an A.B. in Biochemistry and Asian Studies from Dartmouth College and a J.D. from Yale Law School.


James Bramwell

Executive Vice President, Sales and Customer Excellence

James Bramwell is our Executive Vice President, Sales and Customer Excellence. Mr. Bramwell is responsible for our Americas, Europe and global Strategic Partners commercial organizations and enhancing our customer experience. Previously, he served as Executive Vice President of the Americas and led the Avantor Global Services and Strategic Partners organizations. Mr. Bramwell served in several roles at VWR, including Senior Vice President, Strategic Partners, Area Vice President of the Southwest U.S. and Mexico and Vice President of Major Accounts. Mr. Bramwell was one of the founding members of the Avantor Foundation and served in various roles including Board Member, President. Mr. Bramwell earned a bachelor’s degree in business management from Brigham Young University.


Christophe Couturier

Executive Vice President, AMEA

Christophe Couturier is our Executive Vice President, AMEA. He has extensive strategic leadership experience in the life sciences industry. Mr. Couturier leads sales, marketing and customer service for our business in AMEA, as well as the Avantor Business System and its associated LEAN processes globally. Prior to this role, Mr. Couturier was the Executive Vice President, Services. Before joining Avantor, Mr. Couturier led business areas of services, merger integration, general management, finance and consulting at life sciences companies, including more than a decade with MilliporeSigma. He earned a Master of Science in management from ESSEC Business School in France.


Benoit Gourdier

Executive Vice President, Bioscience Production

Benoit Gourdier is our Executive Vice President, Bioscience Production. He is responsible for our Biopharma Portfolio, Production, Research & Development, NuSil, Electronic Materials, manufacturing and engineering offerings to support the current and future needs of our customers. He is also responsible for our Environmental Health & Safety function. Prior to joining Avantor, Mr. Gourdier served as Senior Vice President and General Manager, BioReliance® Contract Testing Services at Millipore Sigma. Earlier in his career, he was Vice President and Head of Bioprocessing at Merck KGaA, Darmstadt, Germany and held accountability for the Asia Pacific region. Mr. Gourdier brings more than 25 years of experience in the life sciences industry, with a track record of driving growth and leading global commercial organizations. He earned a master’s degree in biotechnology engineering from Polytech Clermont.

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Brittany Hankamer

Executive Vice President and Chief Human Resources Officer

Brittany Hankamer is our Executive Vice President and Chief Human Resources Officer (CHRO), responsible for all aspects of our Company’s global human resources organization, including compensation and benefits, learning, talent development, workforce management and employee relations. Prior to assuming her current position, Ms. Hankamer was Senior Vice President of Talent and People Operations at Avantor. In this role, she renewed our enterprise-wide focus on culture and talent including establishing the Diversity, Equity & Inclusion office and building rigorous learning and development platforms. Ms. Hankamer joined Avantor in 2019 and was responsible for driving a global, business-focused people agenda in partnership with the sales, supply chain and manufacturing organizations. Prior to joining Avantor, Ms. Hankamer was Vice President of HR at Conquest Completion Services, LLC after holding a series of progressive HR management roles at Halliburton Energy Services, Fidelity Investments, and Chevron Phillips Chemical Company. She earned a Bachelor of Management at Texas A&M University and Senior Professional in Human Resources (SPHR) from the Human Resource Certification Institute.


Allison Hosak

Senior Vice President, Global Communications and Brand

Allison Hosak is our Senior Vice President, Global Communications and Brand. She is responsible for communications to all stakeholder audiences, corporate marketing, financial communications and change management. Over her tenure with the Company, she has helped foster Avantor’s growth and prominence as a global leader in life sciences. She has built an integrated global communications and brand function from the ground up, and led Avantor’s initial public offering, three corporate rebrands, and multiple mergers and integrations. Ms. Hosak is a member of the Avantor Foundation Board of Directors and leads the company’s corporate social responsibility efforts. She earned an MBA in marketing from Lehigh University and Bachelor of Science in business administration – marketing with a minor in public relations from Kutztown University.

Kitty Sahin

Kitty Sahin

Executive Vice President, Strategy and Corporate Development

Kitty Sahin is our Executive Vice President, Strategy and Corporate Development. At Avantor, Ms. Sahin is responsible for shaping and executing the company’s growth strategy and leading merger and acquisition efforts to enhance the company’s capabilities and accelerate growth. Ms. Sahin came to Avantor following 20 years in corporate strategy and business development roles, having spearheaded successful enterprise growth projects at global organizations across the life sciences, pharmaceutical, and medical technology spaces. Prior to joining Avantor, Ms. Sahin most recently served as EVP, Strategy and Business Development at Novanta. She has held senior-level strategy and corporate development positions at Thermo Fisher, Covidien, and Charles River Laboratories, as well as roles at Corning and Bain & Company earlier in her career. Ms. Sahin earned a Master of Business Administration from The Wharton School at the University of Pennsylvania and a Bachelor of Arts from Yale University.

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Claudius O. Sokenu

Executive Vice President, Chief Legal and Compliance Officer and Corporate Secretary

Claudius O. Sokenu is our Executive Vice President, Chief Legal and Compliance Officer and Corporate Secretary. He is responsible for our global legal, corporate secretary, ethics and compliance functions, including global quality and regulatory. Prior to joining Avantor, Mr. Sokenu was General Counsel, Corporate Secretary and Chief Administrative Officer at Unisys and Senior Vice President and Global Deputy General Counsel at Cognizant. Previously, he was an Equity Partner with two Am Law 100 law firms, Shearman & Sterling and Arnold & Porter, and an Associate and Partner at Mayer Brown. Prior to his 17 years in private practice, Mr. Sokenu served in the Honors Program at the U.S. Securities and Exchange Commission’s Division of Enforcement. He is a fellow with the American College of Governance Counsel. Mr. Sokenu earned a LL.M in securities and financial regulation from Georgetown University Law Center; a LL.M in corporate and commercial law from the University of London’s King’s College London and London School of Economics; and a LL.B with Upper Class Honors from London South Bank University.


Randy Stone

Executive Vice President, Laboratory Solutions

Randy Stone is our Executive Vice President, Laboratory Solutions. He oversees our third-party products, proprietary lab platforms and Avantor Services and is responsible for our Global Supply Chain organization. He joined Avantor in April 2023 after 16 years of service with DuPont, including leadership roles in High Performance Solutions, Investor Relations, Asia Pacific, and most recently as president of the Mobility and Materials business. Prior to his time with DuPont, Mr. Stone held various commercial roles at Arkema, DuPont Dow Elastomers, and Dow Chemical. He is a past chair of the American Chemistry Council’s Durables Group. Mr. Stone holds a B.S. in Economics from South Dakota State University and an MBA from Lehigh University.


Mike Wondrasch

Executive Vice President and Chief Information Officer

Mike Wondrasch is our Executive Vice President and Chief Information Officer. In his current role, Mr. Wondrasch is responsible for all aspects of our Company’s global information and digital technology, including e-commerce, digital marketing and cyber security. Prior to joining Avantor, Mr. Wondrasch led IT organizations at Fortune 100 companies, including PepsiCo, AmerisourceBergen and Mars. Most recently, he served as Global Chief Technology Officer for Bunge, a leading agribusiness and food company. He holds a Bachelor of Science in computer science from Villanova University in the United States and a Master of Science in computer engineering from the University of Pennsylvania.


Our Board brings diverse and relevant experience that guides our strategy.


Our Scientific Advisory Board steers our innovation priorities and accelerates solutions for our life science customers.