Implementation and evaluation of an investigational drug service–led approach for concomitant medication reviews in clinical trials

Abstract Purpose This report describes the implementation, workflow structure, and outcomes of a centralized, investigational drug service (IDS)–led process for concomitant medication reviews in oncology clinical trials. This initiative aimed to improve standardization and enhance protocol compliance by transitioning initial concomitant medication review responsibilities to IDS pharmacists. Summary A dedicated IDS pharmacist role was established to support centralized concomitant medication reviews, ensuring a standardized and efficient process. This initiative included developing a structured request system, electronic documentation, and protocol-specific concomitant medication review guides to enhance consistency. Over a 24-month evaluation period, IDS pharmacists completed 1,052 concomitant medication reviews, averaging 43.8 reviews per month. Drug-drug interactions were identified in 34.3% of cases, with the highest prevalence observed in phase 1 trials. IDS review times remained consistent, with a mean system-tracked time of 1.31 hours per review. However, delays in medication reconciliation emerged as the primary bottleneck, often prolonging review completion. A financial analysis confirmed the program’s sustainability, demonstrating that the billable fee-for-service model effectively supported its implementation. Despite these successes, challenges remained, including variability in protocol interpretation and limited guidance on herbal and supplement use. Conclusion The IDS-led concomitant medication review model improved workflow standardization while supporting operational efficiency and financial sustainability. This approach provides a scalable framework that can be adapted to other clinical trial programs and expanded to include ongoing medication monitoring.