BEBAC  Ing. Helmut Schütz

US – FDA

Drug-drug Interactions (DDI)

On 24 October 2017 the FDA’s Center for Drug Evaluation and Research (CDER) published two draft Guidances for Industry

  1. In Vitro Metabolism- and Transporter-Mediated Drug-Drug Interaction Studies
  2. Clinical Drug Interaction Studies — Study Design, Data Analysis, and Clinical Implications
  1. This guidance is intended to help drug developers plan and evaluate studies to determine the drug-drug interaction (DDI) potential of an investigational drug product. It focuses on in vitro experimental approaches to evaluate the interaction potential between investigational drugs that involves metabolizing enzymes and/or transporters. This guidance also discusses how in vitro results can inform future clinical DDI studies. The appendices of this guidance include considerations when choosing in vitro experimental systems, key issues regarding in vitro experimental conditions, and more detailed explanations regarding model-based DDI prediction strategies.
    If an in vitro assessment suggests that the sponsor should conduct a clinical DDI study, the sponsor should refer to a related guidance addressing the conduct and interpretation of clinical drug interaction studies (draft guidance for industry entitled Clinical Drug Interaction Studies — Study Design, Data Analysis, and Clinical Implications).

  2. This guidance helps sponsors of investigational new drug applications and applicants of new drug applications evaluate drug-drug interactions (DDIs) during drug development and communicate the results and recommendations from DDI studies.
    This guidance focuses on the conduct of clinical studies to evaluate the DDI potential of an investigational drug, including: (1) the timing and design of the clinical studies; (2) the interpretation of the study results; and (3) the options for managing DDIs in patients. A related FDA draft guidance for industry entitled In Vitro Drug Metabolism- and Transporter-Mediated Drug-Drug Interaction Studies focuses on how to assess the DDI potential of a drug in vitro and how to use the results from those assessments to inform clinical DDI studies.

Together, these two guidances describe a systematic, risk-based approach to assessing the DDI potential of investigational drugs and making recommendations to mitigate DDIs and will replace the 2012 draft guidance entitled Drug Interaction Studies – Study Design, Data analysis, Implications for Dosing, and Labeling Recommendations.