About Us

The science-based clinical trial supply leader

Clinical Services International (CSI) is a world leader in the sourcing and management of quality certified commercially available medicines (comparators, concomitant medication, rescue medication) for clinical trials.

Headquartered in London and with operations in the UK, Germany, Japan and the USA, we provide efficient solutions and serve global trials. We are passionate about customer service, quality, innovation and making rapidly available safe medicines. Our long standing experience in intelligent sourcing and clinical trials enables us to provide custom made solutions to address the most complex requirements. We accelerate drug development and reduce timelines by providing a fully integrated service.



A strategic partner in Clinical Trial Supplies


25 years’ experience

In drug development and clinical trial supplies


Worldwide access

Sourcing from Europe, USA, Latin America, and Asia Pacific


95+ Manufacturers

We work directly with all big pharmaceuticals and generic manufacturers

CSI's Growth and Excellence

At CSI, we expertly source and distribute medication as well as ensuring operational excellence of our services. As we grow through improving our client portfolio and expanding our sourcing outreach, the key to our success is our market knowledge, our broad network and long standing relationships with global suppliers and manufacturers, robust SOPs and quality focused operations.

Our committed and trusted team work closely with highly qualified and vetted suppliers to follow trends in the market, proactively anticipate and provide additional solutions in a challenging environment. While clients see our value through the whole supply chain process, when we integrate early in the trial process, our unique experience and clinical trial supply requirements ensure the comparator selection and sourcing strategy always aligns with the trial protocol and regulatory submission.


“It has been very beneficial working with the CSI team. They have excellent scientific expertise, clearly understood the challenge, and provided outstanding solution. Their global reach allowed us to tap into many markets. They are customer focused, result driven and we enjoyed working with them. Well done Team! .“

Leading Gene Therapy Biotechnology Company, Director of Drug Product, Formulation and Stability

“I am truly extremely pleased that CSI managed to achieve the purchasing and delivery milestones which one could say “mission impossible” considering the tight market situation and strict requirement to test a batch which lead to the needs to reserve stock for weeks. a very big thank you to csi team for going beyond. without you, we would be at a lost and not able to achieve the FPI milestone. “

Top 5 CRO, Director Clinical Trial Supplies

“Thank you both for high collaboration and pro-activity really appreciate.“

Leading pharmaceutical company

Women's Enterprise Business

At CSI, we have a clear strategy for DEI.

Our DEI strategy achieves a high level of Diversity (the D), adopting fair and equitable treatment for all people (the E) and Inclusion of everyone (the I), even in the most important decisions about the future of our organisation.

60% of our workforce are women. We are multicultural, multi-faith, speak a dozen languages and celebrate and respect our differences. But we all have a SINGLE goal: to serve our clients and accelerate drug development for the benefit of patients by providing gold-standard service in clinical trial supplies.

Our team

Our team has extensive experience in drug development

Our team has extensive experience in drug development, successful design and the execution of clinical trials. We therefore understand and appreciate the complexities involved in sourcing the most appropriate medication.

We use our science-based approach, operational expertise and global experience to effectively, ethically, and efficiently specify, source and supply comparators and devices. This approach is crucial to influencing better patient outcomes.



Project Manager, Clinical Trial Supply