Leadership Team

Kevin O‘Brien

Kevin O‘Brien

President, North America

Kevin O’Brien serves as President of North America for Merz Therapeutics, where he leads commercial strategy and execution, including field sales, managed markets, medical affairs, marketing and operations, across the U.S. and Canada.

Mr. O’Brien understands the value of developing novel treatment options for neurological conditions and continually demonstrates Merz’s commitment to the movement disorder community through advocacy partnerships and awareness initiatives. Since joining Merz in 2017, he has overseen the U.S. FDA approval of Merz’s neuromodulator for the treatment of sialorrhea (excessive drooling) and as a first-line treatment for blepharospasm, two debilitating conditions associated with neurological conditions, including Parkinson’s disease, ALS and cerebral palsy.

Mr. O’Brien is a global healthcare executive with more than 30 years of experience leading teams and product launches in neurosciences, medical aesthetics, plastic surgery and dermatology. Prior to joining Merz, Mr. O’Brien spent more than 16 years at Allergan, most recently as Executive Director of Medical Aesthetics for Canada. At Allergan, Mr. O’Brien led global teams in the U.S., Canada and Asia Pacific, with a focus on China, Japan and Korea. Before Allergan, Mr. O’Brien had a successful career with J&J and Boston Scientific.

Mr. O’Brien received his juris doctor degree from Western State University and his bachelor’s degree from Saint Mary’s College of California.

You can view Mr. O’Brien’s LinkedIn profile here.

Lesly Charanza

Lesly Charanza

Vice President, Market Access

Lesly Charanza serves as Vice President of Market Access for Merz Therapeutics, where she is responsible for leading the U.S. market access strategy across multifaceted payer, reimbursement and distribution verticals.  Prior to Merz Therapeutics, Lesly was the Vice President, Market Access, Reimbursement and Patient Support Services for Heron Therapeutics’ oncology and pain franchises. During her time at Heron, Lesly led the strategy and tactical implementation of market access, payer coverage, patient and provider support programs and all reimbursement functions, including the market access launch strategy for two new products and the relaunch of a third.

Lesly has more than 30 years’ experience in the pharmaceutical industry managing successful market access teams across injectables and oral products. She has built an award-winning career where she is well-respected as a proven leader and patient warrior.

Lesly received a bachelor’s degree from Baylor University and continues to reside in Texas with her family.

You can view Lesly’s LinkedIn profile here.

Rachel Chase

Rachel Chase

Vice President, Human Resources and Communications

Rachel Chase is the Vice President of Human Resources and Communications of North America for Merz Therapeutics. Rachel is responsible for human resources, learning and development, corporate communications, facilities and meeting planning for Merz Therapeutics North America as well as the Shared Competence Center in North America.

Since joining Merz in 2009, Rachel played an integral role in the integration of three organizations assisting the U.S.’s entry into the Neurosciences and Aesthetics marketplace. She held various HR and communications roles with increasing responsibility in North America between 2011 and 2015. Rachel was selected for the International Perspectives Program in 2014 representing less than 1% of the global organization. She held roles in the global HR team before being appointed to Regional Head of Human Resources for Latin America in 2016. Most recently, she completed a two-year international assignment where she was selected to serve as Business Planning Director located in Frankfurt, Germany reporting directly to the CEO. Prior to joining Merz, Rachel held various human resources roles in the software industry at ScriptLogic and APEX Analytix.

Rachel is a member of the Society of Human Resources Management (SHRM) with a Senior Professional in Human Resources (SPHR) certification from the Human Resources Certification Institute (HRCI).

Rachel holds a B.S. in business administration with a concentration in human resources from the University of North Carolina at Greensboro.

You can view Rachel’s LinkedIn profile here.

Terry Crandall

Terry Crandall

General Counsel, North America

Terry Crandall serves as General Counsel, North America for Merz Therapeutics, where she heads the legal and compliance team for all aspects of the therapeutics business in the U.S. and Canada.

Terry strongly believes that the legal and compliance department best serves the company by operating in a solution-oriented manner, helping to find appropriate ways to support the success of Merz and the achievement of its objectives. Named one of the Top 25 Women in Biotech in 2020 by the Healthcare Technology Report, Terry enjoys rolling up her sleeves and partnering with the business in search of the most effective ways to reach healthcare professionals and patients while maintaining the highest standards of ethics and integrity.

Terry joined Merz Therapeutics with more than 25 years of experience in the pharmaceutical industry and begun her in-house career with GlaxoSmithKline where she held a number of roles within the Legal Department over the course of 16 years. In 2009, Terry joined ViiV Healthcare, a global joint venture between GlaxoSmithKline, Pfizer and Shionogi focused on the development and commercialization of HIV medicines, as General Counsel and Chief Compliance Officer. Following her 8-year tenure at ViiV, Terry served as General Counsel and Chief Compliance Officer for Ironshore Pharmaceuticals, where she focused upon the commercialization of ADHD medications.

Terry received her Juris Doctor degree from the University of North Carolina at Chapel Hill, and bachelors’ degrees in English and psychology from Bucknell University.

You can view Terry’s LinkedIn profile here.

Chad Duncan

Chad Duncan

Chief Financial Officer, North Ameirca

Chad Duncan is the Chief Financial Officer of North America for Merz Therapeutics, where he partners across the organization to drive the financial strategy and execution.

Chad is a diverse finance leader with broad experience across the healthcare industry including pharmaceutical, diagnostics, medical devices, services, and software. Prior to joining Merz Therapeutics, Chad was the Vice President Finance at Syncardia Systems leading finance for the manufacturer of the only commercial artificial heart. Before Syncardia, Chad held several finance leadership roles at Siemens Healthineers across the diagnostics, imaging, and healthcare software divisions in a mixture of global, U.S., and Asia Pacific focused roles. He worked in various large established and startup businesses within the organization. He led the commercial finance group for a global diagnostics division, as well as, established two new business units within the company as the head of finance, including the enterprise services group in Japan creating long term partnerships with hospitals and the digital incubator group in the U.S. focused on early stage healthcare software ventures.

Chad has a Master of Business Administration from Boston University and a bachelor’s degree from George Washington University.

Chad’s LinkedIn profile can be viewed here.

Yannick Grosskreutz

Yannick Grosskreutz

Country Manager, Merz Pharma Canada Ltd.

Yannick Grosskreutz is Country Manager, Therapeutics for Merz Pharma Canada, where he leads the strategy and commercial operations, including sales, marketing and medical affairs.
Yannick is dedicated to supporting health care professionals in fulfilling their mission to improve patient outcomes. He strives to build partnerships and believes in adding value by providing our neurological products, expanding scientific knowledge, and facilitating education.

Prior to joining Merz Pharma Canada in February 2020, Yannick held several roles of increasing responsibility at Merz’s global headquarters in Frankfurt, Germany, most recently as Head of Global Marketing where he was instrumental in driving Merz’s patient-focused communication strategy, international educational programs, and neuromodulator clinical program. From 2003 through 2011, Yannick held various roles in marketing, medical affairs, and sales at Altana Pharma/Nycomed. Over his career, Yannick has acquired significant experience launching new brands and indications, patent expiries, life cycle management, business development projects, as well as, educational and research projects.

Yannick Grosskreutz holds a Ph.D. from the Max Planck Institute for Brain Research (Germany), a MSc in Biology from the J.W. Goethe University (Germany), and a M.B.A. from the University of Wales (UK). He lives with his wife and two kids in Oakville, Ontario.

You can view Yannick’s LinkedIn profile here.

Hadley Iliff

Hadley Iliff

Senior Director, Regulatory Affairs and Product Safety

Hadley Iliff serves as the Senior Director, Regulatory Affairs and Product Safety for Merz Therapeutics, where she leads strategy and execution of new drug and biologic approvals, maintenance of existing products, and safety reporting and pharmacovigilance. Ms. Iliff is dedicated to continuing to pursue new indications and product approvals to provide more available treatments for patients with neurological conditions. Since joining Merz in 2014, Ms. Iliff has managed or contributed to the approval of four new first-line indications for Merz’s neuromodulator, including its first for pediatric patients. Prior to working at Merz, Ms. Iliff worked as a Research Scientist in a computational biochemistry laboratory.

Ms. Iliff holds a Master of Arts in Biochemistry from Duke University, a Master of Business Administration from the University of North Carolina at Greensboro, and a Bachelor of Arts in Biochemistry from Oberlin College.

You can view Ms. Iliff’s LinkedIn profile here.

Rebecca McKinnon

Rebecca McKinnon

Vice President, Medical Affairs

Rebecca McKinnon, Ph.D., serves as Vice President, Medical Affairs for Merz Therapeutics, where she leads medical affairs strategy and execution, including, field medical science liaisons, investigator-initiated trials, medical education support, medical communications and medical information in the U.S.

Dr. McKinnon has been with Merz since 2010 and is committed to providing the highest level scientific and clinical support within the medical community. Prior to joining Merz, Dr. McKinnon was a Pharmaceutical Consultant with IMS Health, where she had the opportunity to partner with multiple companies in creating strategic portfolio assessments during the development of new products, indications, and the life-cycle management of existing products.

Dr. McKinnon received her Ph.D. in Pharmacology and Toxicology from the University of Western Ontario in London, Ontario, Canada.

You can view Dr. McKinnon’s LinkedIn profile here.

Jose Naranjo

Jose Naranjo

Vice President, U.S. Marketing

Jose Naranjo is the Vice President of U.S. Marketing for Merz Therapeutics, where he leverages his more than 20 years of global and U.S. marketing, sales, and operations experience in the pharmaceutical industry in his role championing our U.S. product portfolio.

Before joining Merz Therapeutics in 2022, Jose was the Vice President of Marketing and Commercial Operations at Theramex, where he led commercial strategy and operational excellence. Before Theramex, Jose held leadership sales, marketing, and operations roles at GlaxoSmithKline throughout the U.S., Europe, and Puerto Rico.

Jose obtained his Bachelor of Law degree as well as his Ph.D. from Universidad Complutense de Madrid, and an MBA from the University of North Carolina at Chapel Hill.

You can view Jose’s LinkedIn profile here.

Tom Welsh

Tom Welsh

National Sales Director

Tom Welsh serves as National Sales Director for Merz Therapeutics, where he brings more than 25 years of sales experience to his role leading the U.S. field force, including sales strategy across private practices and academic institutions as well as field training.


Tom joined Merz in 2010 as a Territory Business Manager. With his passion for coaching and continued customer and cross-functional success, Tom has taken on many roles of increasing responsibility within the sales organization over the past decade, including as Regional Sales Director and Director of Key Accounts before being named National Sales Director in 2021.


Tom received a bachelor’s degree in business administration from Simpson College. He resides in Raleigh, NC with his wife and three sons, who benefit from his passion for coaching and mentoring as Tom is an active coach with their travel sports teams.


You can view Tom’s LinkedIn profile here.