At TASK we value our people. If you would like to join us hop on to the “careers page” and apply to advertised vacancies.

You can also stay up to date on TASK news by following us on LinkedIn. 


Professor Andreas Diacon 

Andreas Diacon is the Founder of TASK, Chairman of the Board and TASK’s Chief Scientific Officer. He is a trained physician and spent many years in patient care in internal medicine, pulmonology, and the intensive care unit. Prof Diacon is now a full-time clinical researcher focused on advancing novel anti-tuberculosis agents and regimens towards the patients that need them.

Amongst other achievements, Prof Diacon was awarded a Rector’s Award for Outstanding Research at Stellenbosch University, the Swiss TB Research Award and the Scientific Prize from the International Union Against Tuberculosis and Lung Disease for his exceptional contribution towards research. He has more than 200 publications to his name and is Professor Emeritus at Stellenbosch University.

Most recently Prof Diacon has been leading TASK’s effort to establish a branch in Europe.

Johann De Bruyn

Johann de Bruyn,  TASK’s Chief Executive Officer, is a Chartered Accountant and completed his MBA through Bradford university in the UK. He has been active in senior leadership across various industries over the past two decades, working with multi-national teams driving transformation and growth. His focus at TASK has been on broadening the company’s value proposition through diversification and change management in a digital era.

Melissa Mitchell

Melissa Mitchell is TASK’s Director of Strategic Projects. She has held various operational and strategic roles at TASK since 2011, which allows her to drive growth through a wealth of broader industry knowledge. Most recently she successfully established TASK Eden, a new business venture in diversified clinical trials in a research naïve region of South Africa. Melissa holds a BSc in Chemistry and an MBA from Stellenbosch University.


Gerben van den Hoogen

Gerben van den Hoogen is TASK’s Clinical Executive. He completed his master’s in clinical epidemiology through Radboud University, Nijmegen, the Netherlands. Gerben has over 20 years’ experience in general epidemiology, health policies, laboratory services to clinical trials, both in the Netherlands and South Africa, and clinical research site operations. He is currently elected in the South African Clinical Research Association (SACRA) Exco and has been with TASK since 2020, overseeing laboratory, data management, quality/academy/regulatory, and facility teams.

Riana Stander

Riana Stander is TASK’s Operational Executive, supporting TASK with business operations in achieving the organisation’s goals and strategic intent, a role she has held since 2020. She brings a wealth of experience from a successful career in clinical research and health services.

Previous to her current role, Riana was TASK’s regulatory lead and site start up specialist and prior, regulatory manager.


Dr Linda Mureithi

Dr Linda Mureithi is TASK’s Medical Executive. She is a medical doctor with over fifteen years of
clinical and research experience, working with public, academic and non-profit sectors. She has
expertise in clinical research methods, epidemiology, biostatistics, evidence-based health care,
health systems and policy research. She holds a Masters of Public Health degree (specialising in
Clinical Research) from the University of Cape Town.

Science Officer

Dr Caryn Upton

Dr Caryn Upton has a background in health science and medicine.
Since joining TASK in 2017 she has worked on numerous clinical trials with a wide range of variability regarding the type of research (phase 2 or 3), the complexity of the trials and various patient populations.
Caryn has recently been invited to multiple protocol development teams to add her experience in the field and in implementation of clinical trials early in trial development so as to make the trials more practical on a site level.

Study participant recruitment

Clinical site teams

Brooklyn Chest

TASK Clinical Research Centre (TCRC)


Delft & Mfuleni

Services teams


Data Management





Support teams


Human Resources (HR)

InformationTechnology (IT)