Real-world prevalence of potential drug-drug interactions involving oral antineoplastic agents: a population-based...

We aimed to gain insight into the real-world prevalence of potentially significant drug-drug interactions (DDIs) involving oral antineoplastic agents using nationwide data in Korea.

The data from the 2016 and 2017 Health Insurance Review and Assessment Service-National Patients Sample (HIRA-NPS) of South Korea were used. The drugs prescribed concomitantly with oral anticancer drugs were screened for the potential DDIs by using two international DDI databases: Lexicomp^TM and Micromedex®. Potentially significant DDIs were defined as DDIs with a severity rating of "major" or higher from at least one reference. The DDIs were classified into category 1 if the severity ratings were major or higher using both references.

Overall 5657 cases of DDIs in 2925 patients (26.4%) and 1640 cases of category 1 DDIs in 997 patients (9.0%) were identified among 11,076 patients receiving oral anticancer drugs. The prevalence was highest among the targeted agents (63.2%) followed by traditional (21.2%) and endocrine agents (19.3%). The common potential clinical consequences were increased risk of corrected QT interval prolongation (36.7%), reduced efficacy of antineoplastic agents (30.4%), and increased toxicities of antineoplastic agents (8.0%). Polypharmacy and the duration of oral cancer treatment increased the likelihood of potential DDIs in addition to individual antineoplastic agents.

This study showed that potentially significant DDIs with oral antineoplastic agents were prevalent in real-world practice. Recognizing the high prevalence of DDIs among patients taking oral antineoplastic agents is a necessary step toward improving the clinical outcome.