Rifampin Drug-Drug-Interaction Studies: Reflections on the Nitrosamine Impurities Issue

Clinical development of new drugs may require dedicated drug-drug interaction (DDI) studies, such as to evaluate the effect of cytochrome P450 3A induction on the pharmacokinetics of investigational drugs. However, as a result of N-nitrosamine impurity findings in marketed rifampin formulations, the application of rifampin in DDI studies has been halted. This mini-review considers the root cause and impact of the nitrosamine impurity as well as alternative options for the continued conduct of DDIs.

Automated summary

This article discusses the discovery of nitrosamine impurities in rifampin formulations and the impact of this discovery on drug-drug interaction studies. Alternative options for conducting drug-drug interaction studies are also proposed.