Viroclinics-DDL Diagnostic Laboratory is a leading diagnostic and clinical trial operation service company supporting clinical and preclinical studies for drug and vaccine development for prevention and treatment of virus infections.


Our Purpose

Transforming research, advancing health for you

Our Vision

We transform clinical research to deliver the promise of precision and predictive medicine to help people live healthier lives

Our Values

Excellence, Boldness, Commitment, Respect

Our teams are guided by shared values to Advance Research, Advance Health

Our heritage in specialty labs, combined with our experience in central lab services enables us to develop research techniques that will underpin the next generation of clinical trials. A new kind of research where diagnostics are driven by clinical data, and insights, supported by specific therapeutic expertise.

We are committed to helping our customers deliver the next generation of human-centric healthcare and more affordable medicine for all.

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Viroclinics Biosciences operates at a global level, being the preferred virology testing laboratory for several of the top-10 Biopharmaceutical companies. As a virology contract research organization, we serve the biopharmaceutical community with our preclinical, clinical diagnostic, assay development and clinical trial logistics services. Our extensive experience with clinical and preclinical studies for viruses, including our specialty in respiratory viruses, puts us at the forefront for supporting the development of vaccines, antibodies and antiviral compounds targeting viral infectious diseases. Our staff consists of over 390 well-trained, dedicated scientists and technical experts, and our projects are supported by an extensive network of key opinion leaders as consultants. Through collaboration with the Erasmus MC Viroscience Lab, we offer combined benefits of scientific knowledge and technical ability maintained at both laboratories. This enables Viroclinics Biosciences to support customers with the best virological knowledge available. Our uniquely consultative approach to business means we nurture deep client relationships in order to fully understand their needs and provide optimally customized research programs and project solutions.



Viroclinics-DDL Diagnostic Laboratory is a cutting edge lab service organization with state of the art facilities including laboratory BSL 2 and BSL 3 facilities and a samples processing facility in New Jersey, USA. Viroclinics-DDL has adopted a high quality standard in all operations, testing procedures and reporting. The quality management system is based on NEN-EN-ISO 15189, GLP and expanded with elements of GCP, to comply with regulatory requirements and facilitate regulatory submissions.

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Viroclinics-DDL Diagnostic Laboratory was founded in 2001. It has since grown into a company nearly 400 FTE of dedicated scientists and technical experts, and operates within a network of key opinion leaders and consultants.

In 2010 the ISO 15189 quality system was accredited. With the implementation of this quality system Viroclinics was able to generate high quality assay data in clinical studies that were used in registration filings for new vaccines and antiviral drugs by large and small pharmaceutical companies.

As of September 2012 the company migrated to the Rotterdam Science Tower, a new high tech science facility. At this new location the company occupies 4500 m2 office space and new laboratory facilities, accommodating BSL 2 and BSL 3 work.

In 2017 the company expanded its footprint with a 1500 m2 lab in Schaijk, dedicated to preclinical services at BSL 2 and BSL 3 level. In Schaijk the company also implemented a GAP III facility dedicated for work with polio viruses.

Viroclinics Biosciences and DDL Diagnostic Laboratory joined forces in 2020. The joint strengths, capabilities, and increased laboratory capacity of the new group created a more complete portfolio of services for clients, from early stage pre-clinical work to large scale phase 2/3 trials, as well as post-marketing studies.

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COO, Deputy CEO

Hans Bunschoten joined Viroclinics in 2008. Previous to this he held various positions within the pharmaceutical industry concerned with drug discovery and the transition of leads into drug candidates for human testing. As a consultant he advised several large pharmaceutical companies in distinct areas of drug development.

Hans was trained in immunology and virology at the National Institute of Public Health and University of Pennsylvania and obtained a PhD from the University of Utrecht. His pharmaceutical career began at Organon Biosciences where he headed multidisciplinary teams in vaccine and drug discovery research. Subsequently, he worked as a Director of Preclinical Development at a Dutch start-up company and as a management consultant to pharmaceutical companies. Hans has authored many publications and is inventor of numerous patents.

Konrad Stadler

Chief Scientific Officer

Dr. Konrad Stadler has 20+ years of international experience in vaccine R&D in the public and private sector for animal and human health.

Konrad joined Viroclinics-DDL in September 2021 from the German Center for Infection Research (DZIF) where he acted as Program Director for vaccines. Prior to DZIF, Konrad held global leadership positions at CEVA Santé Animale and Boehringer Ingelheim Animal Health. Before he served the International Vaccine Institute (IVI) in Seoul, South Korea, as Head of the Microbiology Department and Novartis Vaccines in Italy as Senior Scientist.

Dr. Stadler received his master in Biochemistry and his Ph.D. in Virology from the University of Vienna, Austria. In addition, he was a Postdoctoral Fellow at the Vet School, University of Utrecht, The Netherlands, and at Chiron Vaccines in Siena, Italy.



Chairman of the Scientific Advisory Board

AOAlbert Osterhaus co-founded Viroclinics B.V. and is its Chairman of the Scientific Advisory Board.

As professor of Virology in Rotterdam, Utrecht, and Hannover, Ab Osterhaus has a long track record as scientific researcher and PI of numerous major scientific projects. At Erasmus MC he has built the >40 persons virology diagnostic lab and the >100 persons viroscience research lab. His research programme followed a novel integrated “viroscience” concept, bringing together world leading scientists in molecular virology, immunology, epidemiology, pathogenesis, and intervention studies on human and animal virus infections. After having handed over the chairmanship of the Erasmus MC Viroscience lab in 2014,  he is currently establishing the new Research Centre for Emerging Infections and Zoonoses (RIZ) at TiHo Hannover and The Artemis One Health Research Institute in Utrecht.

Major performances under Ab’s scientific leadership include the discovery of more than 50 new viruses of humans and animals or new hosts for known viruses (e.g. human metapneumovirus, coronaviruses, influenza viruses), the elucidation of the pathogenesis of major human and animal virus infections and the development of novel intervention strategies. These include strategies for AIDS, viral hepatitis, influenza, and other major respiratory infections. Discoveries of Osterhaus’ team have enabled health authorities to effectively combat outbreaks of diseases like SARS and H7N7/ H5N1 influenza. These include strategies for AIDS, viral hepatitis, influenza, and other major respiratory infections.

In the past five years, besides the acquisition of major multi-million research programmes from Dutch governmental organisations (e.g. NGI, NWO, FES, TI-Pharma, ministries) Osterhaus` team has successfully acquired numerous international and prestigious research grants from EU FP7 and ERC programmes, NIH, Bill and Melinda Gates and WHO.

While Ab continues to recruit talented researchers and attract national and international funding, he actively participates in experimental design and laboratory work, passing on his expertise to new generations of researchers. In addition, he shares his knowledge to the benefit of society through his advisory role to several national and international public health committees.

The spin-off, Viroclinics, is among his societally relevant successes, allowing effective testing and refining of diagnostic and other intervention strategies.

Awards, prizes, guest lecture invitations, (co-)organiserships of international meetings and editorships of scientific journals further highlight his international recognition. He has acted as mentor for more than 60 PhD students, holds several key patents and is the author of more than 1100 papers in peer-reviewed journals, together cited more than 50,000 times, his H index is more than 90. Most of all, Ab Osterhaus firmly believes scientists have a role to play in translating their knowledge for the benefit and protection of society.



David brings over 15 years’ experience in building different functions, from finance and tax to legal and HR, through various stages of a company’s lifecycle. He previously worked as CFO or VP Head of Finance at reputed organizations such as Coyote Logistics, Land Life Company, Zamro, Greetz and Ernst&Young since 2004.

He has a Master of Science in International Business at the Maastricht University (NL), and a Bachelor of Business Economics at the Hogeschool Zuyd, Sittard (NL).

Working closely together with the rest of the leadership team and the heads of business, his key responsibilities are to develop and execute a new vision and strategy for a global finance function at Cerba Research and Viroclinics-DDL, focus on continued profitable growth. 




Vice President Quality Assurance

Elina is employed at Viroclinics since 2007. She started as Director Quality Assurance. In addition, Elina became Director HRM and member of the management team in 2012. Elina studied food microbiology at the agricultural university of Wageningen in the Netherlands and started in 1987 as microbiologist at the largest dairy company in the Netherlands. Several functions are performed, all related with quality assurance. Elina was appointed as Vice President Quality Assurance and HRM in 2015.



Vice President Legal

Olaf joined Viroclinics at the end of 2006. With a background as an attorney at law and as legal counsel with the Technology Transfer Office of the Erasmus University Medical Center Rotterdam, the Netherlands, Olaf has acquired extensive experience drafting, negotiating and managing contracts in the biotechnology sector.  Olaf studied tax law at the University of Tilburg, the Netherlands, and graduated in 1998. He subsequently went on to obtain an LL.M in international law from the University of Minnesota, USA, after which he joined the Dutch law firm AKD in 2001 working in its intellectual property law section. Olaf completed his professional training as an attorney at law in 2004.

In 2004 Olaf moved to the Erasmus MC to work as legal counsel for its technology Transfer Office. In this position he assisted with the start ups of several spin-out companies of the Erasmus MC, including Viroclinics Biosciences B.V.

In 2006 Olaf left the Erasmus MC Technology Transfer Office and started as legal counsel for three Erasmus MC spin-outs, ViroNovative B.V. and Viroclinics B.V.. In 2011 Olaf joined Viroclinics’ management team fulltime as Director Legal.



Vice President Business Development

Paul Zoeteweij has a PhD in Bio-Pharmaceutical Sciences and spent 5 years post-doctoral at the US National Institutes of Health (NIAID/NCI) to specialize in immunology and virology. Subsequently he spent 7 years at Iomai Corporation, a small biotech company in the USA, as senior scientist in vaccine development. Paul joined Viroclinics in 2007 as Director Contracted Research, and soon after as Director Clinical Services. Since January 2015 he is VP Business Development.



Leen-Jan is responsible for Business Development and one of the founders of DDL. He received his Ph.D. in molecular virology from the Erasmus University of Rotterdam, the Netherlands. He has specialized in molecular typing of infectious organisms such as hepatitis B and C, human papillomavirus and respiratory viruses. Dr. van Doorn has published more than 180 papers in international scientific journals as well as various book chapters.

Renee van der Laan

VP Human Resources

Renee joined Viroclinics-DDL in 2021 as VP HR. Renee completed her MBA at Henley Business School. Later in her career, she obtained a Master in Culture and Change. She started her career at Sea-land Service, Inc. , a global container carrier where she was accountable for EMEA as HR director. She has extensive experience as international HR director and Board member in a broad range of industries amongst others in logistics, chemicals, pharma and business services. Renee has an in-depth experience with M&A, cultural and structure change, talent development, organizational effectiveness and employee relations. Recently she developed herself in Corporate Governance and financial Risk management for Non-Executive Boards.

Desiree van der Kleij


Desiree van der Kleij joined Viroclinics-DDL in 2020. Previously she held various management positions at Contract Research Organizations.  After obtaining her PhD in Immunology at Leiden University Medical Center, Desiree started her career at TNO as project manager, leading multidisciplinary projects and teams. Subsequently she headed a diagnostics laboratory at Sanquin Diagnostics and then started her career in the pharmaceutical industry as Managing Director of Sanquin Pharmaceutical Services. She transferred to Eurofins BioPharma Product Services in 2016 as Manager QC and then Business Unit Manager and joined Viroclinics-DDL as General Manager of the  DDL business unit in 2020. Since 2022 Desiree fulfills the role of Chief Operations Officer.