Our Team

Our team of experienced chemists, project managers, and support staff values each client and is dedicated to moving their projects forward. We are family-owned and operated, and our small size allows us to be accessible, responsive, and to act quickly. Customers consider us for our technical expertise and outstanding history of FDA compliance, but they choose us for our engaging people found in every department from purchasing to process development.

Learn more about select members of our team below.

President & CEO

Tadgh Prendeville

Tadgh joined Regis in March 2022. Prior to Regis, Tadgh was the President of ARx LLC, a family-owned CDMO, specializing in novel drug delivery systems that improved the onset of action and bioavailability of drug substances. During his time at ARx LLC, Tadgh oversaw significant growth through multiple NDA approvals and new product launches and numerous technology developments. Prior to ARx LLC, Tadgh consulted to the pharmaceutical industry with BSM (now part of Efeso). In this role, Tadgh worked with numerous big and small pharma companies to improve operations and R&D practices.

Tadgh earned his Master of Engineering Science from the University College Dublin, Ireland, and his MBA from the University of Baltimore.

CFO & COO

Burr Martin

Burr Martin joined Regis Technologies, Inc. as Chief Financial Officer in May 2006. In this role, he was responsible for the financial operations of the company, including accounting, financial planning, treasury, and risk management. In the years following, he assumed responsibility for manufacturing and business development as Chief Operating Officer.

Prior to Regis, Burr was Vice President of Corporate Planning & Investment Analysis at RR Donnelley, a global provider of print and print related services. Prior to RR Donnelley, Burr worked in a variety of roles for The Quaker Oats Company, with a focus on international finance and expanding Gatorade into Latin America and Asia. Earlier, he spent five years in Brussels, Belgium setting up a European Coordination Center. He began his career at The Northern Trust Company.

Burr Martin received his Master of Business Administration degree from the University of Chicago and is a graduate of Hamilton College.

Vice President, Chemistry

Alan Henderson, Ph.D.

Alan has worked in the Pharmaceutical/CRO/CDMO industry for over 22 years. He joined Regis as the Vice President of Chemistry in 2021. He earned a First Class Honors degree (BSc) in Chemistry from the University of Edinburgh in Scotland and a Ph.D. in Organic Chemistry from the University of Cambridge in England.

Alan started his post-academic career at Pfizer in the UK, where he worked as a Team Leader within the Medicinal Chemistry Department. He then moved to AMRI (now Curia) in the US where he would spend the next 19+ years of his career. In his time at AMRI, Alan had many different roles of increasing responsibility including management of customer projects, leadership of internally funded cross-functional research programs, Director-level site leadership for the largest customer project within the business unit, Director-level Technical Leadership within a cGMP Manufacturing site and Director-level Business Excellence support within a cGMP Manufacturing facility. He has overseen projects at all levels of Research and Development from the very early stages of Discovery through to API Validation. Alan has also been an author, co-author or inventor on 27 publications/patents.

Director of Solid State Chemistry

Ronald L. Mueller, Ph.D.

Dr. Mueller has more than 25 years in the pharmaceutical industry and over 20 years of preformulation and Solid State Chemistry experience. After earning his B.Sc. in Chemistry, he studied Chemistry at the Karlsruhe Institute of Technology in Germany as a Fulbright Student Scholar and Quadrille-Mobay Fellow. Ron received his Ph.D. in 1990 from the University of Nebraska–Lincoln in Organic Chemistry.

Ron led Solid State Chemistry teams to contribute to CMC Regulatory modules for several medications (NDAs/MMAs), Drug Master Files and ANDAs. His industrial background includes Johnson-Matthey, West Pharmaceutical Services, GlaxoSmithKline, Bristol-Myers Squibb and Sanofi-Winthrop. He served in professional affiliations as a volunteer in United States Pharmacopeia, Parenteral Drug Association, Product Quality Research Institute, and as the Chair for Industrial Microscopy at the Eastern Analytical Symposium. He is the co-author on many publications and the co-inventor on several patents and/or patent applications.

Ron joined Regis as Director of Solid State Chemistry in March 2019. The SSC service provides salt, cocrystal, and polymorph screening and selection activities to provide suitable crystallation processes during all development phases for Regis' Custom Pharma clients. A dedicated laboratory is now established at Regis and features state-of-the-art equipment run by Ron and a team of experienced solid state chemists.

Director of Technical Operations and Process Chemistry

Siead Zegar

Siead has worked in the pharmaceutical and fine chemical industry for over 25 years. He received his Bachelor’s Degree from the University of Illinois at Chicago. Siead began his career as an R&D chemist at Pelron Corporation and was promoted to Production Supervisor where he was responsible for overseeing R&D and production operations. He joined deCODE, a wholly owned subsidiary of deCODE Genetics as a lab manager and advanced to Associate Director of Process Research and Development. At deCODE Siead was responsible for overseeing the Process Research and Development group which focused on the development/optimization and scale-up of APIs.

Siead has worked at Regis since 2009. His career with Regis began as a senior chemist in the chemical development/production group and he has recently been promoted to Director of Technical Operations and Process Chemistry. Siead oversees the Process Chemistry group and is responsible for the development of new processes and transfer of technology to pilot plant and full scale production.

Director of Quality

Rebecca Centko

Rebecca has worked in the pharmaceutical industry for over 20 years. She received her Bachelor’s Degree in Chemistry from the Illinois Wesleyan University. Rebecca joined Pharmacia/Pfizer as a medical chemist and worked in the Combinatorial Chemistry group. There, one of her main responsibilities was to design and synthesize therapeutic agents to treat CNS diseases.

In her previous role as the Director of Project and Account Management, Rebecca was responsible for leading the Project Management group at Regis since 2007. Most recently, Rebecca was promoted to the Director of Quality. Her knowledge, industry experience, and dedication, enables Rebecca to maintain a high level of quality compliance at Regis.

Director, Business Development, Custom Pharma

Daniel Weissmueller

Dan joined Regis in 2001 working as an Analytical Chemist. He quickly established himself as a leader and an asset to Regis by successfully retaining key roles in Analytical Development, Operational Excellence, Validation, Quality Control, Quality Assurance and most recently Business Development. As the Director of Business Development, he is responsible for establishing and building strategic partnerships, and growing Regis' CDMO business. His extensive experience, leadership skills, expanded education, and over 20 years of experience in API Development, allow him to understand customer needs from IND-enabling efforts through commercialization, and develop and maintain collaborative relationships built on trust.

Dan earned his Master's Degree in Quality and Regulatory Sciences from Northwestern University and a Bachelor's Degree in Chemistry from Benedictine University. Notable accomplishments at Regis include leading the transition of the Analytical Department to new and more efficient laboratories, supporting HPAPI efforts, leading the global CMC/DMF regulatory efforts supporting 3 different NCE's, and developing a sustained quality culture that yielded ten years of successful FDA inspections with no objectionable findings (i.e. zero Form 483 observations).

Business Director, Chromatography

Melissa Wilcox

Melissa received her BSc in biology and environmental science from Western Michigan University (Kalamazoo, MI). In her 25-year career in the field of chromatographic analysis and purification, she has served in R&D, marketing, sales, analytical development, and tech service roles. In 2016, Melissa joined the chromatography team at Regis and is currently the Business Director for Regis’ chromatography business, which supplies chromatography consumables to a broad range of industries.

Prior to joining Regis, Melissa worked for Grace Discovery Sciences where she held leadership roles in product development, marketing, sales, and tech service. Her work focused on leading cross-functional teams to develop, market, and sell new HPLC/Flash/Prep instrumentation, HPLC columns and consumables, and flash chromatography products. She has several publications in the chromatography field and is a named inventor on a patent for Evaporative Light Scattering Detection technology. She serves on many scientific organizations' technical committees including ASTM, AOAC, AHPA, and is an active member in ACS (Secretary of CANN, a subdivision of the Chemical Health and Safety Division).

Associate Director, Analytical Development

Gregory G Griffin

Greg Griffin received his bachelor’s degree in Chemistry from Illinois State University and has over 10 years’ experience working in the pharmaceutical industry.

Greg joined the Regis Team in 2011 in the Quality Control department. During Greg’s time at Regis, he has transitioned working between Quality Control and Analytical Development departments as a Chemist, and most recently as the Manager of Analytical Development. Greg has played an integral role in several successful validation programs, and has mentored numerous analytical teams supporting multiple NCEs in drug development. He has built up a very strong reputation within Regis and our clients with his organizational skills, leadership skills and technical knowledge. In his current role as Associate Director, Analytical Development, Greg leads our Analytical Development team, and is an integral part of the Management team.

Associate Director of Quality

Shellene Rodriguez

Shellene has worked in the Pharmaceutical and fine chemical industry for over 30 years. She earned a B.A. Degree in Chemistry from Carthage College.

Shellene’s career started as a QC Chemist for Aldrich Chemical in Sheboygan Falls Wisconsin and continued at Cerac, Inc in Milwaukee Wisconsin where she evaluated fine organics, anhydrous solvents, and highly pure metal alloys. Shellene joined Regis in 1997 as a second shift QC Chemist. In 2001, Shellene transitioned to the Quality Assurance department as a QA Associate, and currently holds the position of the Associate Director of Quality.

Shellene has been hosting customer audits and FDA inspections at Regis since 2008 and has been involved in three successful on-site PAIs and four FDA inspections with zero 483s. Shellene’s longevity at Regis gives her unique insight to company procedures and processes. Her experience and knowledge allow Shellene to maintain a high level of quality compliance at Regis.

Associate Director of Quality Control

Christine Gutierrez

Christine began her career in the pharmaceutical industry more than 15 years ago at Grifols Biologics in Los Angeles, California. Upon relocating to Illinois, she worked at Abbott Laboratories prior to joining Regis in 2008.

Christine graduated from the University of Guam with a Bachelor’s degree in Biology and in 2018 she earned an MBA with emphasis in Project Management from Elmhurst University. She started at Regis as a QC Chemist and eventually became the QC Services Manager overseeing stability and reference qualifications. Christine also served as a project manager where her leadership skills and focus on customer service, led to the successful completion of several projects. As the Director of Quality Control, Christine continues to take pride contributing to Regis’ commitment to quality and integrity, and is a proven integral part of Regis' ongoing success.

Associate Director, Project Management

Jason Lin

Jason has worked in the pharmaceutical industry for over 10 years and has been with Regis since 2019. He earned his Bachelor’s Degree in Biology from University of Iowa and a Master in Business Administration from Western Governors University. Prior to joining Regis, Jason held various roles in R&D, process development, technology transfer, and project management in the industry. Jason has a wide breath of project management experiences managing R&D, process/technology transfer and custom manufacturing projects, ranging from pre-clinical, clinical through validation and commercial.

At Regis, Jason leads our high functioning Project Management Group supporting our customers to achieve the project objectives. Jason and his team are the primary point of contact for the customers at Regis and help ensure Regis maintains focus to guarantee the customers’ needs are met. These needs include timelines, scope, and regulatory requirements.

Manager of Process Engineering

Dragan Ristic

Dragan is a chemical engineer with over 25 years of industrial experience in process development, technology transfer, and manufacturing of active pharmaceutical ingredients and specialty chemicals. Prior to joining Regis, Dragan had worked for AstraZeneca in Europe and deCODE Genetics in the Chicago area in different engineering and scientific roles from a process engineer to a director of chemical operations. He held leadership roles in process optimization and technology transfer from the bench to pilot plant and commercial scale focusing on product quality, practicality and safety. He also coordinated the Pilot Plant construction, equipment installation, and start up at AstraZeneca.

Dragan is focused on expanding Regis’ capabilities in potent compound handling and processing.

Chromatography Applications Scientist

Ed Franklin, Ph.D.

Ed is an analytical chemist with over 15 years of experience in chromatography research. He earned his bachelor’s degree in biochemistry from Duquesne University and his Ph.D. in analytical chemistry from the University of North Carolina at Chapel Hill. His research experience includes fundamental investigations of the kinetic performance of modern liquid chromatography materials and their use in small and large molecule applications.

Prior to joining Regis, Ed worked at Restek Corporation as a senior scientist in the HPLC product development group. In his current role, Ed develops HPLC and SFC methods for applications of Regis’ line of chromatography products.