Study close-out represents the final phase of clinical trial conduct at either the site level when a site completes participation or the study level when the entire trial concludes. This phase ensures orderly completion of all outstanding activities, proper documentation and archival of trial records, appropriate disposition of investigational products and biological samples, and preparation for potential future inspections. Thorough close-out is essential for regulatory compliance and reflects the quality standards maintained throughout the trial.

Site close-out activities typically include resolution of all outstanding data queries, completion of all case report form pages, collection and reconciliation of all investigational product, preparation and archival of the investigator site file, notification to the IRB/IEC of study completion, and discussion of participant follow-up plans if applicable. A close-out monitoring visit verifies completion of these activities and documents the state of the site file at study conclusion. The investigator acknowledges responsibility for maintaining essential documents for the required retention period.

The transition from active conduct to archival requires careful attention to document preservation and accessibility. Essential documents must be organized, indexed, and stored in conditions that ensure their preservation for the regulatory-required retention period, typically at least two years following the last marketing approval or study termination. Storage arrangements must enable retrieval if documents are requested for inspection. Contact information for responsible parties must be maintained to enable communication even years after the trial concludes.