Leadership team

Tom Breen

Chief Executive Officer

Tom is an enterprise leader with deep knowledge and understanding of international agribusiness. He has held various leadership positions at Monsanto, Bayer, and Nutrien across a range of domains, including sales and marketing, technology development, supply chain operations, corporate strategy, and business transformation.

John Fernandes

Chief Financial Officer

John has experience in strategy, finance, and continuous improvement. He has held roles at NZX, Goldman Sachs, JB Were, MediaWorks, Elevation Capital, and Spark.

David Siegel, PhD

Head of Research and Development

David has more than 15 years of international R&D experience in agriculture, human, and animal health. He formerly held various leadership roles at Bayer Animal Health and Boehringer Ingelheim in Germany and New Zealand, with a particular focus on drug discovery, product development, and marketed product defense.

George Reeves

Head of Intellectual Assets and Strategic Partnerships

George has 30 years of experience as a leader in agriculture, animal and human health, and FMCG. Formerly, he was the Marketing Manager for Farm Animal at Elanco and Bayer Animal Health, and also worked at Bayer Consumer, Colgate, and SC Johnson in New Zealand, Australia, and the UK.

Product Development

David Colsell

Head of Formulation and Development

David has over 30 years of experience in chemical product development and innovation. He is committed to technological progress and thrives on the challenge of taking new ideas from concept to commercialization, for which he has a proven track record.

Bishal Adhikari, PhD

Senior Formulation Scientist

Bishal brings over a decade of experience in pharmaceutical research and product development. He previously worked at Argenta and has a deep understanding of the innovation behind drug delivery and formulation.

Hossein Etemadi, PhD

Formulation Scientist

Hossein has eight years of academic and industry experience in formulation and product development, as well as research and design of novel drug delivery platforms based on hydrogel polysaccharides.

Stefanie Maslek, PhD

Senior Scientist Bolus Chemistry

Stefanie has over 10 years of experience in chemistry laboratories. She brings expertise in process development, material functionalization, and laboratory health and safety. Her previous work experience ranges from start-up companies to crown research institutes, with projects focused on improving the circular economy and environment.

Wayne Hu, PhD

Laboratory manager

Wayne has 16 years of experience in pharmaceutical GMP and R&D labs, with a focus on analytical chemistry. He is proficient in laboratory operations, including method development, quality control, regulatory compliance, and waste management.

Erica Yin

Head of Analytical Development

Erica has over 20 years of experience in the pharmaceutical and agriculture fields, specialising in analytical method development, validation, and product specification. She has extensive knowledge of product characterisation, cGMP, and ICH guidelines. She holds a master’s degree in Pharmaceutical Science from the University of Auckland.

Maria Mevicci Tenebroso

Senior Laboratory Technician

Maria holds a Bachelor of Science in Chemical Engineering from the Cebu Institute of Technology and has demonstrated expertise in process optimisation, materials science, and commercial upscaling. She joins our team after working as a research and development engineer at Atlas Fertilizer Corporation, a subsidiary of Sojitz Corp.

Jiaoying Wei

Laboratory Technician

Jia joined the RBT team in 2021. She is an enthusiastic and skilled laboratory technician with experience in R&D work.

Charlie Jackson

Laboratory Technician

Charlie holds a bachelor’s degree in Science, majoring in Medicinal Chemistry, from the University of Canterbury. He also has experience working with cows and sheep, as he lives on a farm.

June Park

Laboratory Technician

Jun holds a bachelor’s degree in Science with a major in Chemistry and has two years of hands-on experience in a food testing lab, focusing on analytical chemistry.

Global Research and Clinical Trials

Kirsty Bardoul

Head of in vitro and in vivo studies

Kirsty has experience in the start-up biotech industry, with a background in agritech R&D. Besides her research communication, data organisation, and analysis skills, she has a strong track record in leading and managing clinical trials and field studies.

Abigail Chase, BSc(Hons) BVMS PhD

Veterinary Scientific Affairs Manager

Abi is an experienced production animal veterinarian with a strong focus on research. She has worked in various clinical roles in both the UK and New Zealand. For the past eight years, Abi was the Technical Product Manager for a large pharmaceutical company, working with veterinarians and farmers on sustainable treatments for production animals on pasture.

Hans Hockey


Hans has many years of experience in study design, statistical power, analysis, and biometrics in human pharmaceutical drug trials and animal studies. In the past, Hans has worked overseas for global leaders in human pharmaceuticals, the foremost being Pfizer.

Meryem Drief, PhD

Science Analyst

Meryem has a background in agronomy, field research, and data analysis, holding a PhD in Soil Science from Lincoln University. Prior to joining Ruminant BioTech, she served as a field research assistant at Lincoln Agritech. Since her arrival in 2023, she has contributed significantly to data analysis, database management, and reporting.

Intellectual Assets and Strategic Partnerships

Caitlin Burnett

Head of Intellectual Property

Caitlin is an established registered Trans-Tasman Patent Attorney with broad commercial experience across numerous technologies and jurisdictions. She handles the complexities of leveraging intellectual property rights, including patents, trade marks and brand strategy, copyright, registered designs, and trade secrets, across both IP and common law.

Mark Vickers

Regulatory Manager

Mark has been a veterinarian and industry consultant for international and start-up companies in regulatory affairs for over 30 years. His areas of expertise include GMP manufacturing, product development, and the planning and conduct of GLP and GCP clinical trials for veterinary medicines. These trials were conducted for bolus solutions registered and sold in New Zealand and Australia.

Tiffany Siegel, PhD

Market Access and External Collaborations Manager

Tiffany is a scientist with over 15 years of experience in analytical development and mass spectrometry, with expertise in drug metabolism research and regulatory aspects. Her strong collaboration skills drive successful external partnerships, enhancing interdisciplinary teamwork and fostering innovation.

Programme management, Finance and Administration

Maggie Sullivan

CERF Manager

Maggie has 19 years of experience as a project / programme manager with broad experience across several business sectors, including pharmaceuticals, telecommunications, and government agencies.

Verity Groves

Finance Manager – Grants and Projects

Verity is an Associate Chartered Accountant who takes care of all our financial management, keeping the numbers and processes in order and providing support to the CFO.

Natalie Connell

Executive Assistant

Natalie is an experienced executive assistant with five years of proven success in providing top-level support to executives. Skilled in managing calendars, coordinating meetings, and maintaining confidentiality. Strong organisational abilities, attention to detail, and adept at prioritising tasks.