Drug-drug interaction trials incompletely described drug interventions in ClinicalTrials.gov and published articles: an observational study

Abstract

Objectives: The aim of the study was to evaluate the completeness of intervention description in ClinicalTrials.gov and corresponding journal articles for registered and published drug-drug interaction (DDI) trials because complete and transparent description of interventions is particularly important for DDI.

Study design and setting: Observational study of completed interventional trials on DDIs with up to two drugs within the Intervention registration element in ClinicalTrials.gov until October 2015. We used the Template for Intervention Description and Replication items to assess the quality of intervention description in both ClinicalTrials.gov Descriptive Information section and matching publications. Corresponding articles were identified in March 2019.

Results: The description of 1,180 drug interventions registered for 642 DDI trials mostly lacked information on the intervention provider (99.7%), adherence strategies (99.2%), procedure (83.8%), location (71.3%), and dosage form (60.7%). Generic name (82.5%), dose (70.8%), and duration of administration (65.6%) were most frequently reported. Among 51 trials that had data reported both in ClinicalTrials.gov and publication, 60.8% were in phase 1. Less than half of 96 interventions had clear and matching description of dosage form, procedure, and route of administration in both sources.

Conclusion: DDI trials did not sufficiently report components required for complete intervention description. Further improvements in ClinicalTrials.gov registration requirements, including phase 1 trials, and more stringent publishing requirements for essential data on drug interventions, are needed to prevent patient risk in clinical practice regarding concomitant medication use.

Keywords: Bias; Databases; Description of drug intervention as topic; Drug interaction; Reporting; Transparency; Trial registration.