Whether it involves assessing eligibility criteria, monitoring safety, determining baseline values, or demonstrating the efficacy of an investigational drug, laboratory testing of clinical, immunological, and in some studies genetic biomarkers is an integral component of clinical trials.
Historically, most clinical trial laboratory testing was conducted by local laboratories organized by individual principal investigators. Collecting and consolidating data from multiple local laboratories, each using different testing methodologies, reference ranges, and standard operating procedures (SOPs), frequently resulted in data inconsistencies, errors, delays, and increased costs for sponsors. Common issues included mislabeled kits, missing samples, and incorrect tests. As a result, laboratory data received at the end of a trial often exhibited high error rates.
This challenge became even more complex as clinical trials globalized. Analyzing data with such inconsistencies often required months of intensive data cleaning before the results could be considered reliable and analyzable.
To address these challenges, the concept of the central laboratory was introduced in the mid-1980s. It was driven by the need for consistency in specimen collection, standardized analytical methods, uniform reporting, and consolidated data across multiple sites. A central laboratory is an institution exclusively responsible for laboratory assessments in a clinical trial, providing services that range from conducting laboratory analyses and compiling test reports to managing courier services for the delivery of laboratory kits and biological samples to and from clinical sites.
The value of central laboratories, compared with high-volume diagnostic laboratories, lies in their ability to ensure consistency across all aspects of laboratory operations. This includes standardized specimen collection kits, uniform analytical platforms, established SOPs, consistent equipment, reagents, and calibration standards. Lack of standardization in any of these areas can lead to variability and inconsistency in results.
For example, standardized collection kits improve ease of use for site personnel responsible for sample collection. Central laboratories also train site staff on proper sample collection, packaging, and labeling procedures, significantly reducing human errors that can result in sample misidentification or reporting inaccuracies. In addition, central laboratories standardize analytical methods, specify appropriate equipment and blood volume requirements, and ensure consistent report formats across all sites.
Central laboratories maintain dedicated logistics teams that understand sponsor requirements and establish robust relationships with courier agencies. These logistics arrangements account for specialized shipping needs, such as dry ice, and ensure that specimens are transported under controlled conditions. Customized tracking systems provide real-time visibility of samples while in transit.
Furthermore, central laboratories operate under uniform SOPs, quality assurance standards, and integrated IT platforms. They deliver laboratory data in a single, consistent file format using standardized reference ranges and units, as required by sponsors. Central laboratories are also well-versed in regulatory requirements across multiple geographies and remain informed about evolving regulatory landscapes.
By delivering globally harmonized, statistically meaningful data with consistency over time, central laboratories play a critical role in clinical trials. In contrast, diagnostic laboratories are designed to provide individual patient snapshots, have limited scalability, and operate under cost-driven models that are not aligned with the rigor and consistency required for pharmaceutical-grade clinical research.
These considerations firmly establish the essential role of central laboratories in the successful execution of global clinical trials.