Clinical Services International (CSI)

Dr Vanessa Dekou

Trial Continuity Champion

As biosimilar development continues to accelerate worldwide, securing reliable access to originator reference medicines has become one of the most important factors influencing programme success. Comparator products are required throughout development, from analytical characterisation and non-clinical studies to Phase I and Phase III clinical trials, providing the evidence needed to demonstrate bio-similarity to regulators. 

Reference biologics are often expensive, subject to regional supply constraints, and require stringent handling and documentation. Sponsors must also navigate differing regulatory expectations and complex international supply chains as development programmes become increasingly global. 

Unlike conventional pharmaceutical procurement, comparator sourcing for biosimilars requires scientific understanding, regulatory expertise and robust global logistics. Each study has unique requirements, with considerations such as sourcing region, batch consistency, product availability and documentation influencing procurement strategy. Many biologics also require validated cold chain storage and transportation, with temperatures ranging from 2–8°C to ultra-low conditions of –80°C, making product integrity essential throughout distribution. 

Long development timelines add another layer of complexity. Biosimilar programmes frequently span several years, requiring sponsors to forecast demand accurately and maintain continuity of supply to avoid delays that can impact study timelines and increase costs. Additionally, factoring in the shelf life of the product is integral to the protocol planning process to ensure the stock lasts over the duration of the study.  

Early planning is therefore becoming an increasingly important part of biosimilar development. Working with an experienced clinical trial supply partner allows sponsors to evaluate sourcing strategies, assess potential risks and establish reliable procurement plans before recruitment begins. 

Clinical Services International (CSI), a global comparator sourcing and clinical trial supply specialist, approaches comparator procurement through scientific project planning. Study protocols are reviewed to understand the specific medicine requirements, geographical considerations, regulatory documentation and projected demand before a sourcing strategy is developed. Depending on the programme, this may involve local sourcing, central procurement, manufacturer-direct supply or a hybrid approach designed to balance availability, compliance and cost. 

"Biosimilar development demands far more than simply sourcing a reference product," says Vanessa Dekou, CEO of Clinical Services International and a member of the Board of Advisors for the UCL School of Health. "Success depends on rigorous planning, regulatory understanding and building resilient global supply strategies from the earliest stages of development. At CSI, we are proud to play a role in helping biosimilar developers bring these medicines to market. Every successful biosimilar has the potential to improve patient access to life-changing treatments by offering more affordable alternatives and supporting that journey is something we are genuinely passionate about. By helping sponsors overcome complex sourcing challenges, we are contributing to a future where innovative therapies become more accessible to healthcare systems and the patients who rely on them." 

Global manufacturer relationships are another important consideration. Access to comparator medicines often depends on established supply networks capable of sourcing products across multiple markets. CSI maintains direct relationships with more than 200 manufacturers and suppliers across 60 countries, providing access to both branded originator medicines and biosimilars for international clinical studies. 

This global reach is particularly valuable for biosimilar developers pursuing regulatory submissions across different regions, where authorities may require comparator products sourced from specific countries or markets. 

Documentation is equally critical. Regulatory submissions require comprehensive product traceability, with authenticated comparator medicines supported by documentation such as Certificates of Analysis, Batch Release Certificates and Statements of Authenticity, especially when exporting to APAC, for instance. CSI maintains a clear chain of custody throughout procurement and distribution, providing confidence in the integrity of study materials. 

For biologics, validated cold chain management is essential. Temperature excursions can compromise product quality and potentially invalidate study materials. GDP-compliant storage, validated packaging, continuous temperature monitoring and contingency planning all contribute to maintaining product integrity from manufacturer to clinical site. 

CSI provides cold and ultra-cold chain storage and distribution at 2–8°C, –20°C and –80°C, supporting studies across a broad range of therapeutic areas including oncology, immunology, ophthalmology and haematology. To date, the company has supplied medicines to more than 1,200 clinical trials worldwide. 

Beyond logistics, comparator sourcing has become an important element of overall development strategy. Early engagement with supply specialists can improve forecasting, reduce procurement risk and help sponsors anticipate potential market shortages before they affect study timelines. 

As the biosimilar market continues to expand, comparator sourcing is recognised as a strategic component of successful clinical development rather than a purely operational activity. Organisations that combine scientific expertise, regulatory knowledge and established global supply networks are helping sponsors overcome procurement challenges while ensuring patients receive safe, high-quality medicines throughout every stage of clinical research.