Meet our Team.

  • Team member
  • Team member
  • Team member
  • Team member
  • Team member
  • Team member

Michael Graves


Michael has spent his entire career in medical devices and pharma and brings more than 20 years operational experience to ViCentra. Michael has led both large operations and small start-ups, ranging from prefilled insulin syringes, insulin pumps, wound care, disposable hospital equipment, ECG monitors and permanent skin fillers. Having worked with diabetes for more than 14 years, 10 of which were spent with Novo Nordisk, Michael brings diabetes business understanding to ViCentra.

Click here to get in touch with Michael.

Tim Oakes

Tim Oakes

CTO and Co-Founder

From a young age, Tim could usually be found surrounded by tools and prototypes, building his own boats and rigging elaborate zip lines in his garden. Now an award-winning design engineer, Tim has over seven years’ experience in the medical device field, working on projects as diverse as drug delivery platforms to laparoscopic surgical instruments. Having grown up with a father with Type 1 diabetes, Tim has first-hand knowledge of the challenges of trying to incorporate complex medical devices into daily life and is driven by a deep desire to create products that help make life easier.

Click here to get in touch with Tim.

Alex Evans

Alex Evans


Alex spent the early years of his career leading teams in customer-facing environments, experiences which firmly enforced for him the importance for every business to place their customers at the heart of all they do. Returning to university to pursue his interests in this area and utilise his first-hand experience, Alex studied Marketing Management, graduating with a first-class honours degree. In 2014, his passion for strategically creative marketing led him to enter the Chartered Institute of Marketing’s UK-wide competition, The Pitch, which, after beating out twenty five entrants, his team won. Since joining ViCentra, it’s clear that Alex’s love for a good competition hasn’t been satisfied by his success so far (in fact, he can often be found engaged in head-to-head battles on the ViCentra ping pong table!) and that he is looking forward to applying his marketing strategies and know-how to the future development of ViCentra.

Click here to get in touch with Alex.

Hiddo During

Research & Development Manager

Hiddo started his career in the semiconductor industry installing and qualifying high-tech systems, gaining a profound set of practical skills. Growing to on-site project manager made him quickly realise that the combination of engineering and management constitutes a great role to work in. When starting to work on the development of medical devices seven years ago, he then proudly followed in the footsteps of his grandfather and is now responsible for the R&D team at ViCentra. In his current role, Hiddo brings a great combination of practical as well as engineering and management experience to the leadership team, setting ambitious goals within his team and unceasingly focusing on creating healthcare products that put people first.

Click here to get in touch with Hiddo.

John Tullett

Director of QA/RA

After starting his career in R&D, John soon saw the light and began his move into Quality and Regulatory in the late 1980s, just in time for the introduction of the PPE and medical devices directives. Over the course of his 30 year career, sci-fi fan John has worked with medical devices ranging from Class I through to Class III, as well as secondary packaging for drugs manufacture. During this time, he’s dealt with most of the global markets and acted as the point of contact for the FDA and other notified bodies too. Prior to joining ViCentra, John spent twenty years at SSL International, eight at Smiths Medical and five years at Cogent Healthcare Systems. His expert knowledge of radio and telecoms requirements has been particularly useful in his work at ViCentra, where he is responsible for managing our Quality management systems and ensuring our compliance with the requirements of ISO 9001 and ISO 13485. Despite once swearing he’d never again join a start-up, John secretly enjoys the challenge of setting up systems and taking new products through the accreditation process. John says ViCentra’s relaxed atmosphere also resonates well with him – that and the fact that, here, our individuals really do change the way we do things.

Click here to get in touch with John.

Joost van Kordelaar

Distributor Relationship Manager

Joost studied Medical Imaging and Radiation Therapy at Hanze University of Applied Sciences in Groningen, graduating in February 2015. An ardent sailor, he was an active member of the Groninger Student Sailing Association during his time in the city, spending two years on the society’s board as well as being a board member for the Dutch Student Sailing Cup in 2010/2011 and the Dutch Student Sailing Association in 2011/2012. These experiences sparked Joost’s interest in the commercial field, and with his medical and technical background, he found in ViCentra the opportunity to combine all his passions. Now our Distributor Relationship Manager, Joost is responsible for building and maintaining our relationships with our distributors, working closely with them to ensure that the ViCentra experience is always brilliant, regardless of where in the world you are.

Click here to get in touch with Joost.

Maike Baum

International Product Manager

With her international profile and passion for medical marketing, Maike brings essential global marketing experience within the field of diabetes care to ViCentra. After 4 years in her global marketing role at Novo Nordisk, she relocated from Denmark to the Netherlands to join ViCentra and their mission to redefine diabetes care and work alongside people with diabetes to help them find a little more freedom and flexibility within their day-to-day management. After having launched and driven strategic marketing programmes all over the world, she now looks forward to carry the Kaleido brand across borders and share ViCentra’s vision to drive access to healthcare products that put people first.

Click here to get in touch with Maike.

Marianne Delphin

Software Development Manager

After graduating with a Master in telecommunications and digital signal processing, Marianne acquired 15 years of experience developing embedded Audio related software for various major companies in France and the Netherlands. She then decided to make the jump to the start-up world and the medical software field and never looked back. At ViCentra Marianne now supervises all software developments, ensuring that Kaleido is satisfying all compliance criteria and providing patients with a dependable and flawless user experience.

Click here to get in touch with Marianne.

Nytza van de Geer

Facilities, ICT & Office Manager

Before joining ViCentra, Nytza studied Tourism and Recreation Management, and started her career as an Account Manager in the Food and Beverage industry, selling and implementing hardware and software solutions to the restaurant industry throughout the Netherlands. Following a cross country move, she became Office Manager at a biotech company, producing products to help ensure safe blood transfusions. Nytza loved that the role combined all of her organisational, problem-solving and team-building skills in a dynamic and fast-paced environment, and so jumped at the chance to join ViCentra when looking for her next challenge. Helping to build ViCentra from the ground up, Nytza and her team support our needs across the business, helping our growing company flourish. Needless to say, not much happens around here without her!

Click here to get in touch with Nytza.

Petra Kovarova

Production & Logistics Manager

Petra relocated to the Netherlands from Ireland to share her supply chain knowledge she gained at Eli Lilly, a major pharmaceutical company. Petra has experience in maintaining strategic relationships with suppliers and other internal and external stakeholders, implementing new systems and interfaces and managing optimal stock levels and therefore ensuring reliable supply of medicines and medical devices to patients. Petra’s career has always been customer centric, focused on continuous improvement and open to challenges as she was part of several projects and initiatives on top of her regular responsibilities. This proved to be a great strength at ViCentra and she was shortly promoted from Supply Chain Co-ordinator to Production & Logistics manager where she is now looking after manufacturing and supply chain.

Click here to get in touch with Petra.

Sarah Lee

HR Manager

Travel lover Sarah graduated from Northumbria University with a 2:1 Honours degree in Law, a four year programme which integrated the LPC and gave her a practical and knowledgeable basis for her future in HR. Following her studies, Sarah joined the graduate trainee programme at Hays, the world’s leading specialist recruitment agency, where her performance quickly placed her in the top 10% of the UK division and led to fast track promotions. Following a spell in London where she joined a recruitment consultancy as Team Manager before being promoted to Business & Recruitment Manager, Sarah relocated to the Netherlands, working as a freelance HR consultant across a range of sectors and completing her Master’s degree in Global Human Resource Management. Sarah has a keen interest in people-centred management and was drawn to ViCentra by the opportunity to be involved in HR at an early stage. Now responsible for all aspects of our HR, including recruitment, Sarah is always on the lookout for innovative, talented and fun people to join the ViCentra family.

Click here to get in touch with Sarah.

Tim Hardy

Finance Director

Since qualifying with the Chartered Institute of Management Accounting, Tim has spent 10 years in industry, working across both private and public organisations. Throughout his career, Tim has maintained a keen desire to evolve the traditional role of the accountant to that of Finance Business Partner, striving to add genuine business value at the Board level, through effective stakeholder engagement, financial modelling and decision support. With this focus, and his first class honours degree in Business Modelling and Strategy, Tim brings a wealth of programme financial control, commercial management, strategic business planning and risk management experience to ViCentra. Since joining the ViCentra team, Tim is relishing the opportunity to take our Finance team to the next level. And, when he’s not focusing on all things finance, you might just find Tim out on one of Utrecht’s many mountain biking trails, or off on another surf expedition!

Click here to get in touch with Tim.