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Implications of Modifying Study Eligibility Criteria Post-Initiation of Recruitment


Conference Paper

Allen, C.A.; Yesko, L.; Van Veldhuisen, P.

Society for Clinical Trials 35th Annual Meeting

Philadelphia, PA


Under ideal circumstances, study eligibility criteria are not changed after recruitment begins. However, eligibility criteria are sometimes broadened to address slow recruitment, or are modified to account for changes in standard of care and safety issues. Changes to eligibility after recruitment has started to impact the data collection system, regulatory review processes, and statistical analysis of the study, particularly in a multi-site trial setting. Eligibility criteria modifications will result in changes to the data collection system. Such changes take time to test and implement. The revisions need to be ready at the time regulatory approvals are obtained or interim procedures need ot be developed to guide sites on the data collection process until the changes are implemented. Implementation of the changes can be technically complex depending on the nature of the changes and the timing of regulatory approval for the changes. om a regulatory perspective, changes in eligibility criteria will result in a protocol amendment. This amendment will need to be reviewed by one or more regulatory bodies. This may include the Food and Drug Administration for IND studies, Data and Safety Monitoring Board, but at a minimum each site’s Institutional Review Board (IRB). The review process varies from a few weeks to months and sites may operate under different versions of the protocol for a period of time. Careful monitoring is required to ensure approvals are received and that sites do not use the new criteria prematurely. Modifications to the eligibility criteria must also be considered from a statistical perspective. Care must be taken to ensure that the revision does not change the original assumptions upon which the sample size and study design were based. A recent National Institute on Drug Abuse Clinical Trials Network study will be presented to show how this was addressed in a real trial setting.

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