Objective: To critically evaluate published cost-effectiveness studies of novel drug products requiring less-frequent medication dosing compared to conventional formulations of the same drug substance.
Methods: A search was conducted in the Medline and Embase databases for cost-effectiveness studies published before May 2009 that compared two or more drug delivery technologies formulated with the same active drug substance. The Quality of Health Economic Studies (QHES) grading criteria for cost-effectiveness studies was applied to the selected publications.
Results: The literature search identified approximately 907 articles of which six cost-effectiveness studies met the inclusion criteria. The studies spanned four chronic conditions, were conducted from various international perspectives and used decision-analytic models to project economic outcomes. The base-case results of all six studies indicated that the drug product with sustained therapeutic efficacy was either more effective and less costly ('dominant') or more cost effective than the conventional formulation of the same drug substance. Quality scores ranging from 70 to 84 (scale 0 to 100) were assigned to the studies, with a mean of 78.
Limitations: This review likely did not capture all relevant drug delivery technologies and drug products. Only one reviewer critically evaluated the cost-effectiveness studies and independently assigned quality scores using the QHES grading criteria, which may be limited in its ability to identify poorly analyzed studies.
Conclusion: Evaluation of the published literature suggests that drug products with less-frequent medication dosing can be cost effective when compared to conventional formulations, but assessments are challenging because of complex relationships among therapeutic drug levels, dosing frequency, medication adherence, and health outcomes. Additional product-specific, comparative, pragmatic studies in this area are needed.