A Case Study of Single-Pill Combination Therapy: The Ezetimibe/Simvastatin Combination for Treatment of Hyperlipidemia

In recent years, combination therapy has received growing popularity as a powerful therapeutic tactic for the treatment of diseases. The justifications and benefits of combination therapy are far-reaching, including but not limited to addressing unmet medical needs such as cancer, malaria, and HIV/AIDS, improved clinical efficacy and safety with reduced dosage of a single medication, understanding the underlying science of the disease, alleviating pharmaco-economic impacts, and better drug life-cycle management. Using the ezetimibe/simvastatin combination therapy as a case study, a comprehensive overview of the successful discovery and development of the single-pill combination, Vytorin, is presented in this review. A cursory introduction to combination therapy and the rationale for the ezetimibe/simvastatin combination for the treatment of hyperlipidemia provides an instructive entry point. The discovery and mode of action of simvastatin and ezetimibe monotherapies set the scene for a detailed discussion on the discovery and development of Vytorin, with emphasis on bioequivalency studies, clinical efficacy and safety profile studies, and the economic consequences of the single-pill combination therapy. Large-scale outcome clinical trials are also discussed to demonstrate the long-term effects of Vytorin.