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# Drug-Drug Interaction Assessments Lacking: FDA Research
- URL: https://www.fdaweb.com/drug-drug-interaction-assessments-lacking-fda-research/
- Published: 2024-10-04T12:00:00.000Z
- Updated: 2026-09-14T14:43:13.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5157921

New [FDA research](https://accp1.onlinelibrary.wiley.com/doi/10.1002/jcph.6142?source=email) shows that 22% of new molecular entities (NMEs) approved between 2009 and 2023 required postmarketing requirements (PMRs) or postmarketing commitments (PMCs) to address “knowledge gaps” on drug–drug interaction (DDI) assessments not addressed during development.

“We found that 22% of NMEs had at least one DDI-related PMR or PMC, with a total of 263 that were pharmacokinetic based,” the agency says. “Of these, 67% were for the assessment of drug metabolizing enzymes, which were established most frequently for their evaluation as a substrate, and 28% for transporters, which were established most frequently for their evaluation as an inhibitor. The 89% of PMRs and PMCs that were considered fulfilled had a revision to the United States prescribing information, the majority of which resulted in updated new instructions for use.”

FDA says its research highlights the importance of conducting PMRs and PMCs early in the drug development process allowing broad patient inclusion when the NME is first approved.