Leadership Team

Jamie Macdonald

Chief Executive Officer

Jamie Macdonald is Chief Executive Officer of Parexel. He has nearly 25 years of experience in leading global biopharmaceutical services companies.

Prior to joining Parexel, Mr. Macdonald served as CEO of INC Research, now known as Syneos Health, from January 2013 through September 2016, where he led the company through a successful Initial Public Offering in 2014.

Mr. Macdonald also served as INC’s Chief Operating Officer from July 2011 through December 2012, and previously held several leadership positions in the biopharmaceutical services industry, including Senior Vice President and Head of Global Project Management at Quintiles, now known as IQVIA. Prior to this, he held various senior operational and finance roles at Quintiles. He has previously served on the Board of Directors for the Association of Clinical Research Organizations (ACRO) and as its Chairman in 2015.

Mr. Macdonald’s recent experience also includes serving as Chairman of the Board for Certara, a drug development consultancy with solutions spanning discovery, preclinical and clinical drug development, from 2017 to 2018.

Mr. Macdonald began his career in the pharmaceutical industry with Syntex Corporation (acquired by Roche Holdings, Inc.). A native of Scotland, he holds a B.A. in Economics from Heriot-Watt University in Edinburgh, Scotland and is a qualified Chartered Management Accountant (ACMA).

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Peyton Howell

President, Consulting and Chief Commercial & Strategy Officer

Peyton Howell joined Parexel in May 2018 and leads the company’s Commercial and Consulting businesses along with its Corporate Business Development, Corporate Strategy, Marketing and Corporate Communications functions. In 2020, she led the company’s Biotech and Enterprise Commercial teams to record new business growth.

Peyton has more than 25 years of leadership experience in the healthcare industry and prior to joining Parexel held several leadership positions with AmerisourceBergen, a Fortune 20 company, most recently as President for Health Systems and Specialty Care Solutions, a $50B business unit. She also was President, Global Sourcing and Manufacturer Relations, responsible for leadership of $150B in manufacturer sourcing relationships. In this role, she led the creation of a new sourcing entity in Bern, Switzerland to support global manufacturer relations and a joint venture with Walgreens. Peyton also previously served as President, Consulting Services for the company, managing a portfolio of industry-leading pharma services (including acquisitions) focused on market access, reimbursement, patient programs, specialty pharmacy, specialty logistics and product commercialization.

Peyton also was a founder of Lash Group, growing the company from an early innovator of patient access services to nearly 5,000 employees and serving as President for nearly 10 years following its acquisition by AmerisourceBergen.

Peyton holds a Masters’ in Healthcare Administration (MHA) from The Ohio State University and a Bachelor of Arts in Speech Communication from The University of Illinois at Urbana-Champaign. In 2020 she was named a Luminary by the Healthcare Businesswomen’s Association (HBA). Peyton serves on the Board of Directors of Tandem Diabetes Care, Inc., as well as the Cancer Equity Initiative for Family Reach, a national 501(c)(3) organization dedicated to eradicating the financial barriers that accompany a cancer diagnosis. She currently represents Parexel on the Board of Directors for the Association of Clinical Research Organizations (ACRO).

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Sy Pretorius, MD

President, Clinical Development and Chief Medical Officer

Sy leads the company’s global Clinical Development offering comprising our therapeutic expertise and project delivery to provide best-in-class solutions for our customers, including full-service, Functional Service Provider (FSP) and hybrid models. In this role he provides leadership for all of our Clinical Development functions, including Patient and Site Engagement, Project Leadership, Clinical Operations, Data Operations, Scientific/Real-world Data Organization, Medical Services, Translational Medicine (includes Clinical Pharmacology, Genomics, Modeling & Simulation and Biomarkers), Integrated Delivery and Enablement Office (IDEO), FSP models, Clinical Trial Supplies & Logistics (CTS&L) and Safety Services.

Sy collaborates closely with our biopharmaceutical and life sciences customers in designing and optimizing drug/device development strategies and leading innovations in drug development and clinical research. He has been with Parexel for more than two decades in a variety of roles and countries, overseeing all facets of our clinical and medical operations and holding roles such as Executive Vice President and Chief Medical & Scientific Officer; Senior Vice President & Chief Scientific Officer; Corporate Vice President & Worldwide Head, Early Phase; and Global Head, Clinical Operations, Early Phase.

Sy is passionate about drug development and leads several companywide forums and initiatives focused on clinical trial innovation and further expanding Parexel’s capabilities and service offerings. He is a Medical Doctor (M.B.,Ch.B) with master’s degrees in Clinical Pharmacology (M.Med.Sc), Business Administration (MBA) and a Management of Drug Development (MS) from the University of Southern California. He has and continues to publish and present extensively. In 2017 Sy was recognized as one of the top 100 most inspiring people in the pharma industry by PharmaVOICE magazine.

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Greg Rush

Chief Financial Officer

Greg Rush is Chief Financial Officer at Parexel and brings to the Company more than 25 years of experience leading global financial operations within the CRO and service industries.

Prior to joining Parexel, Mr. Rush served as Executive Vice President and Chief Financial Officer of Syneos Health, Inc. (formerly known as INC Research Holdings, Inc.) from August 2013 to February 2018. In that role, Mr. Rush oversaw the Company’s global financial operations, including Finance, Accounting, Tax, Treasury, Budgeting, M&A and Financial Planning, as well as all Information Technology functions.

Previously, Mr. Rush was Senior Vice President and CFO of Tekelec, a leading high-tech solutions and service provider that was acquired by Oracle. Mr. Rush also held positions of increasing responsibility at Siebel Systems, Quintiles Transnational Holdings, PricewaterhouseCoopers and Ernst & Young. In his roles, Mr. Rush has had repeated success in developing innovative financial management strategies, strong capital structures, high levels of operational support and sound corporate governance. He has experience in both private and public capital markets, completing more than 50 debt and equity financing transactions, including private equity transactions, initial public offerings (IPOs) and secondary offerings.

Mr. Rush is a Certified Public Accountant and holds a Bachelor of Science in Business Administration and a Master of Accounting from the University of North Carolina at Chapel Hill.

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John Bell

Chief Quality Officer

John Bell is Chief Quality Officer and has been with Parexel for over three decades in various roles. In his current role, Mr. Bell leads and oversees quality strategy and initiatives across the organization, and provides oversight and direction to the Quality organization globally.

Mr. Bell has played various, and progressively more senior, roles in Quality including leading Parexel’s Quality organization since 2006. Apart from more traditional Quality functions, such as Quality Management and Quality Assurance, Mr. Bell has also established and managed quality-related groups during his tenure at Parexel.  These include Lean Six Sigma/Operational Excellence (inclusive of training program), Customer Advocacy (client survey and reporting), Data Analytics and Reporting (focused on predictive quality metrics), Data Protection and Privacy, Business Continuity, Training (inclusive of a Learning Management System), and Operational Risk Management. Prior to his current role, Mr. Bell served as Vice President, Head of Quality Management, Clinical Research Services. Previously, Mr. Bell also served as Senior Director, International Integration and Coordination (Early Phase), tasked with financial reporting and integrating new acquisitions. 

Mr. Bell is involved with several professional associations, including serving as a member of the ACRO Ethics and Regulatory Compliance Committee, Drug Information Association, and Research Quality Association (previously BARQA). Mr. Bell has published in a variety of peer-reviewed journals. 

Mr. Bell holds a Diploma in Research Quality Assurance from Anglia College, Cambridge, UK, Diploma, as well as a Bachelor of Social Science from the University of the Orange Free State, Bloemfontein, South Africa.

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Michael Crowley

Chief Administrative Officer and General Counsel

Mr. Crowley is General Counsel and Secretary of Parexel.  In this capacity, he is responsible for the Company's worldwide legal, risk management, ethics & compliance and corporate governance.  

Mr. Crowley brings to Parexel extensive commercial and corporate legal experience. He has provided counsel on a wide range of matters including commercial contracting, strategic alliances, corporate governance, mergers and acquisitions, compliance and ethics and intellectual property. Since joining Parexel in 2009, Mr. Crowley has held several key positions in the Legal & Risk Management organization, including most recently overseeing legal support for the Company’s commercial contracting and clinical operations organizations.  Prior to joining Parexel, Mr. Crowley was Vice President and General Counsel at Netezza Corporation, a publicly-traded technology company. Mr. Crowley was previously with CA, Inc. and Concord Communications, Inc.

Mr. Crowley received his J.D. degree from Northeastern University School of Law. He also holds a Bachelor of Arts degree in History from the University of Miami and a Master of Arts degree in European History from the University of Rhode Island.

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MaryJo Zaborowski

Chief Information Officer

MaryJo Zaborowski is Chief Information Officer at Parexel. She brings more than 20 years of executive technology leadership experience in the delivery of biomedical research and clinical development services for multiple Fortune 500 companies.

Prior to joining Parexel, Ms. Zaborowski directed end-to-end information and technology services for Janssen Pharmaceuticals’ research and development enterprise as Vice President and Chief Information Officer of R&D. Her previous experience also includes roles as Vice President and Information Officer of R&D at Eli Lilly; Senior Vice President, Enterprise Research and Analytics at Ingenix (UnitedHealth Group), and Senior Vice President, Global Head of R&D Informatics and Palo Alto Chief Information Officer at Roche Pharmaceuticals. 

Across these roles, Ms. Zaborowski executed transformative technology innovation and established data science strongholds that enabled new business models and drove competitive advantage for each organization. Her strategy for Parexel includes the application of AI, automation, big data and biosensor technologies to enhance efficiencies, maximize productivity and accelerate drug development timelines.

Ms. Zaborowski holds a Bachelor's degree in Genetics from the University of California, Berkeley. 

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We are always available for a conversation.


Communication Preference

Communication Preference