This is the question raised by a recent study Teesdale et al. (2021) Designed to answer. They first checked the 2016 medical insurance Part D drugs of the top 250 medical insurance Part D drugs based on the 2016 medical insurance Part D prescription drugs.Drug characteristics determined from 2016 FDA Orange BookThe authors used data from the United States to determine whether a drug has undergone a related cost-benefit analysis (CEA) study. Tufts Medical Center Cost-Benefit Analysis RegistryThey also use the Tufts CEA Registry to assess the quality of CEA research.
Based on this method, the following conclusions are drawn:
- Drug spending is highly concentrated. The top 30 drugs accounted for 33.5% of the total expenditure in Part D (48.9 billion US dollars), and the top 250 drugs accounted for 84.1% of the total expenditure (122.8 billion US dollars)
- Endocrinology and Cardiology have the highest expenditure in Part DThe disease areas where medical insurance spends the most on Part D drugs are endocrinology ($23.3 billion), cardiology ($17.5 billion), and pulmonology ($12 billion). You will notice that Oncology is not on the list, in part because many oncology drugs are administered by clinicians and are therefore covered by Medicare Part B (not Part D).
- Most drugs have undergone CEA studies, but many have not“Among the 250 drugs with the largest expenditures in Part D of Medicare, 135 (54.0%) were included in at least one cost-effectiveness study… Drugs with any evidence of cost-effectiveness accounted for 67.0% of the total expenditure on the top 250 drugs.”
- Over time, the importance of CEA research has increasedAs shown in the figure below, the number of drugs undergoing CEA studies has increased over time.