Management Team

Marken is a wholly owned subsidiary of UPS and is a part of UPS’s global Healthcare and Life Sciences (HCLS) unit. Marken is led by Ariette van Strien as President, reporting to Wes Wheeler as President of the UPS HCLS unit. Learn more about UPS and Marken’s Executive Team:

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Wes Wheeler
UPS Healthcare, President

Wes Wheeler, former CEO of Marken, was appointed President of UPS Healthcare in 2019 which provides extensive supply chain management, cold chain, clinical trials, global transportation and other critical healthcare service operations.  The unit includes Marken, Polar Speed, and the company’s 114 healthcare-dedicated facilities.

Wes joined the pharmaceutical industry in 1989 with Glaxo (now GlaxoSmithKline) and worked for 12 years, leaving the company in 2003 as Senior Vice President, Global Manufacturing & Supply. While at GSK, Wes was responsible for the manufacturing merger of GlaxoWelcome and SmithKline Beecham. He has since served as CEO / President at four different companies, including Patheon, Valeant and DSM Pharmaceuticals. Prior to joining GSK in 1989, he worked for 12 years as a project engineer for Exxon (now ExxonMobil). During Wes’ professional career, he has been involved in every key functional area in pharmaceuticals including manufacturing, drug development, supply chain logistics, marketing, and engineering. Wes has lived and worked for many years in Europe and Asia in addition to his many posts in California, New Jersey and North Carolina.

His combination of deep operational experience, and many diverse roles as a leader and the challenges of working in many different cultures has provided Wes with a unique range of perspectives and skills required to transform and grow companies. Wes holds a Bachelor of Science degree in Mechanical Engineering from Worcester Polytechnic Institute and a Master’s degree in Business Administration with an emphasis in Finance. He has two adult children and currently lives in North Carolina with his wife.

Ariette Van Strien

Ariette Van Strien, President, offers 28 years of clinical research experience from Phase I to Phase IV and has held senior executive roles across global marketing and business development, pricing as well as project management and global operations functions. Ariette’s ability to lead global teams has built strong, strategic relationships with major Pharma and CRO companies. Her extensive work on the central lab and clinical side brings a unique perspective of the supply chain to her current role. Since joining Marken in 2010, Ariette has drawn on her experience to position Marken as an industry leader across the clinical trial supply chain, and to develop optimized solutions and new service offerings for Marken’s clients. Ariette has a Diploma as a National Public Relation Consultant, a Baccalaureate of Modern Languages and Biological Sciences, and a Superior French Language degree from the International College of Cannes, France.

Doaa Fathallah
General Counsel and Chief Administrative Officer and Senior Vice President, Polar Speed

As Marken’s General Counsel and Chief Administrative Officer as well as Senior Vice President, Polar Speed Distribution Limited, Doaa Fathallah brings a wealth of pharmaceutical experience to her role spanning nearly two decades. Prior to her appointment with Marken, she served as Executive Vice President, General Counsel & Corporate Secretary for Patheon as well as Vice President, General Counsel – Europe, the Middle East, and Africa for Valeant Pharmaceuticals International. Doaa began her career as an Associate at Foley & Lardner and later at Paul Hastings in Los Angeles, California. She received her Juris Doctorate degree from the University of Southern California and her Bachelor of Science degree in Marketing and Management from the Marshall School of Business at USC.

Andrew Gravatt
Senior Vice President, Finance

Andrew Gravatt, Senior Vice President, Finance leads Marken’s global finance organization. He joined Marken in 2013, bringing with him the financial leadership skills he gained through his previous experience with private equity, public and US companies within manufacturing, logistics and service sector companies. His contributions to Marken’s successful growth through 2015 and 2016 included in-depth financial analysis, preparation and eventual sale of the Marken business to UPS. Andrew is a UK qualified Accountant with a 25-year career in financial management, and he holds a B.A (Hons) in Economics & History from Leeds University. He completed 10 years military service in the UK Territorial forces with a Commission in the Royal Artillery, and holds a RYA Yacht-Master Off-Shore qualification. Andrew lives with his family in West Berkshire, UK and is an avid sailboat enthusiast.

Thomas C. Grundstrom
Senior Vice President – IT Strategy, Technology and Business Analytics

Tom Grundstrom, Senior Vice President, IT Strategy, Technology and Business Analytics leads Marken’s global technology organization. That team is responsible for creating and maintaining the IT infrastructure across the global logistics and distribution network, ensuring that all information systems and platforms are protected and secure, designing a best in class enterprise architecture that responds nimbly to ever changing industry demands,  creatively knitting together bespoke and commercially available software solutions to support operational efforts in all service lines, and providing transparency and data driven decision making via robust business intelligence platforms. Tom Joined Marken with more than 25 years of operations and technology experience in the drug development industry, holding a variety of leadership positions in 4 top CROs. Tom holds a BA in Economics from Wheaton College and a M-DIV from North Park Theological Seminary.

Gerit Offenhauser
Senior Vice President, Global CTD Operations and EMEA Logistics

Gerit Offenhauser is a well versed business leader who has worked the past 20 years in the Life Sciences industry. During that time, he has held various leadership positions in Europe and Asia including senior roles from Strategic to Operations. He served as Director, Project Management Europe and Asia Pacific, managing a team of Project Management professionals conducting 350+ projects in parallel. Before joining Marken, Gerit served as Vice President, Global Logistics Operations and as a member of the Group Executive Board for one of the top tier global central labs. Gerit is a contributing Scientist in a Masters Program at the Center for Stroke Research Berlin, where he is currently teaching “Project Management in Clinical Trials” in the “Master of Science in Cerebrovascular Medicine” at the Charité – Universitätsmedizin Berlin.

Dan Bell
Senior Vice President, Americas Region

Dan Bell joined Marken in 2003 and is Senior Vice President, Americas Region. Dan is a licensed US Customs Broker and a Certified Customs Specialist with 25+ years experience in the life science logistics & temperature control field. His current focus is regulatory and trade compliance aspects for global life science supply chain solutions. Dan has served as a liaison between his clients, customs and the alphabet soup of regulatory agencies, to ensure the maximum level of compliance with Trade laws and regulations. His knowledge and experience in this arena have led to the development of many import strategies that have significantly reduced turn-around times, optimized cost and ensured that mission critical objectives have been met or exceeded. As regulatory scrutiny continues to focus on the temperature controlled supply chain, Dan’s expertise with thermo regulating packaging solutions and temperature logging devices has been critical to meeting the requirements of the recently updated Good Distribution Practices for pharmaceutical transport and similar guidelines.

Navnit Patel, Ph.D.
Senior Vice President, Global Quality Assurance, Regulatory Affairs & Operational Excellence

As Marken’s Senior Vice President, Global Quality Assurance, Regulatory Affairs & Operational Excellence, Navnit Patel brings 25 progressive years of strong experience in Pharmaceutical Quality Assurance, Quality Control and Quality Systems Management globally. Prior to his appointment with Marken, Navnit served at various levels, starting from hands-on Quality Control Chemist to the highest Quality Management position with multiple leading global Pharmaceuticals/Biotech companies. Navnit is a trained Black-belt and a certified coach for Lean Six Sigma. During his career, he developed unique quality tools that efficiently identify and address critical compliance gaps to implement an effectively compliant quality systems based on the requirements of the business. Navnit has a strong educational and technical background with a Ph.D. in Organic Chemistry from SP University, Gujarat, India with over 20 research publications in internationally recognized journals.

Simon Kirk
Chief Technology Officer

Simon Kirk joined Marken in 2010 as Chief Technology Officer (CTO).

With over 20 years of experience in technology systems and development, Simon’s knowledge and expertise have contributed to Marken’s leading, cloud-based IT solutions as well as the corporate IT infrastructure.

At Marken, Simon is instrumental in-house application design and development and production. He is invested in Agile methods for technical leadership to simplify traditional IT approaches to achieve the best outcomes for clients and Marken together. As such, he works closely with internal and external stakeholders to identify and deliver valuable capabilities and facilitate his teams to help them perform at their best.

Simon graduated from one of the United Kingdom’s leading universities, Royal Holloway, University of London with a Masters in Science (MSci) in Physics.

Ernest Batista
Vice President, Inbound Logistics, Americas

As Vice President, Inbound Logistics, Americas, Ernest Batista heads one of Marken’s fastest growing Life Science markets globally. He is also responsible for managing the day-to-day operations of Marken’s Miami branch, overseeing the details of Specialty Logistics on over 20,000 shipments per month.

Since opening the Miami office in 2005, Ernest and his team have grown Marken’s market share through Miami, more than doubling the volume every year for the past several years during an era that has seen the highest level of security regulatory impact on the industry.

Through his time at Marken holding roles increasing in responsibility, Ernest has worked closely with the TSA, Department of Homeland Security and the Customs offices of every Latin American country to establish the processes, implement systems and gain the critical certifications of the Miami Branch to support the Life Sciences industry, making Marken the leading Life Science Logistics Specialist.

Ernest brings over 25 years of Logistics, Regional regulatory and Customs management expertise focused on Latin American from his previous roles at Skynet Express, Ocasa, Zulair Cargo and Tumi.

Frederic Maurice
Vice President, EMEA Logistics

Frederic Maurice is Marken’s Vice President, EMEA Logistics. Frederic Maurice joined Marken in 2004. His expertise includes Customs licensing and IATA certification of the Paris branch and he holds a license to transport controlled drugs as the Regulated Agent in Paris. While with Marken, Frederic has been instrumental in establishing a network of relationships with airlines and handling agents in the area to improve priority handling for Marken clients. Frederic also established the Western European and West African network of agents. With strong experience in temperature controlled solutions and packaging, with additional expertise in shipping biological samples and drugs, Frederic is a key member of the Marken executive team. He holds a Masters degree in Corporate Finance and International Trade from the University of Paris Dauphine.

Leanne Boytler
Vice President, UK and Central European Logistics

Leanne Boytler joined Marken in 2005 and currently holds the role of Vice President, UK and Central European Logistics.

Poh-Meng Cheah
Vice President, Asia Pacific

As Marken’s Vice President for Asia Pacific, Poh-Meng Cheah brings more than 20 years of sales, operational and quality management experience from numerous startup operations within Asia Pacific for both small and large MNCs. Within these functional areas, he has held various leadership positions in APAC across several healthcare related industries including express healthcare logistics, freight forwarding and clinical CMO. Poh-Meng is a certified lead auditor and assessor in a number of business standards including GMP, ISO9001 and 14001, OHSAS and Social Accountability 8000. Prior to joining Marken, he served as Head of Business Development and Marketing covering Asia Pacific for one of the world’s leading clinical CMO. Poh-Meng has a Graduate Diploma in Logistics and Materials Management from Curtin University of Technology in Australia and received his Bachelor of Laws with Honors degree from the University of Exeter in United Kingdom.

Julia Tarasenko
Vice President, Commercial Operations, Europe and the Americas

Julia Tarasenko, Marken’s Vice President, Commercial Operations, Europe and the Americas, joined Marken in 2008. Prior to heading the Commercial Team, Julia managed several European client relationships and led branch operations in Europe. She then moved to the APAC region to oversee Marken Japan operations (based in Tokyo) and Marken Singapore operations as a General Manager. Julia has been instrumental in further developing the APAC network and growing relationships with Marken key clients in the region. Julia served in North America as a Regional Director, East Coast Operations, based in New York. She then joined the Marken Commercial Team overseeing strategic relationships with Marken key global clients. Presently, Julia leads Marken’s global sales operations throughout Europe, North America and Latin America. Julia holds a BA in Philology (Chinese language) and a MSc in Chinese Language, Literature and Culture from Edinburgh University, Scotland, UK.

Julio Villamayor
Vice President, LATAM

Julio Villamayor, Marken’s Vice President, LATAM, brings more than 25 years of experience in International Trade Finance, Supply Chain logistics, Commercial Operations and Marketing. His comprehensive background and experience fuses commercial operations and financial acumen to protect assets, spark organizational growth and drive team performance levels. As Vice President of LATAM, Julio leads South America Operations and is responsible for Miami, Argentina, Chile, Peru, Brazil, Colombia and Mexico Operations. Since joining Marken in 2011, he has held several growing leadership positions from Commercial Operations to Strategic Operations, for both North and Latin America regions. Julio has been instrumental in restructuring our agent’s network, developing teams and markets and positioning Marken’s brand very highly within the Latin America healthcare community. Julio holds an International Trade University degree from U.A.D.E, Argentina and a Masters Degree in Corporate Finance & Business Administration from Austral University, I.A.E School of Business, Argentina.

Nina Vas
Vice President, Clinical Distribution, Cell & Gene Supply Chain

Nina Vas, Marken’s Vice President, Clinical Distribution, Cell & Gene Supply Chain previously served as Managing Director for Fisher Clinical Services Germany. She brings financial, operational, quality and PPI (Practical, Process Improvement) experience managing the performance of the full supply chain which supported the execution of distribution for clinical trials to global destinations. Her background includes importing of drug product (from API to finished goods and ancillaries) with Clinical Research Organizations, Pharmaceutical Importers, owned facilities and third‐party depots.

Jennifer Therrien
Vice President, Marketing

Jennifer Therrien, Vice President of Marketing, leads Marken’s global marketing organization. Jennifer brings 16 years of cross-industry experience, working with iconic global brands including IBM, Thermo Fisher Scientific and Patheon. Jennifer specializes in B2B marketing with expertise in new product development, branding, communications, marketing operations, market development and demand generation. Jennifer received her Bachelor of Science degree in Communication, with dual minors in Marketing and Information Technology, from Rensselaer Polytechnic Institute.

David Lee
Vice President, Global Alliance Management

David Lee, Vice President, Global Alliance Management, joined Marken in 2012. His background and experience covers 23 years in Logistics Account Management and specifically with Clinical Trial Supply Chain since 2007. He was a key figure in developing the inbound sample service for central laboratories in his previous role at DHL Express and has transferred that know how to the successful development of the new Marken / UPS sample service in EMEA. As part of the Commercial Operations Senior Management team, he headed up Global Pricing at Marken for 5 years, and chaired the pricing Committee until 2018. David now leads the new Strategic Alliance Management team across our top 30 clients.