Cheapest generics could save Medicare billions
In Medicare’s prescription drug benefit, switching to generic and lowest-cost options for common blood-pressure drugs could have saved billions from 2018–2022.
*Retrospective analysis of national spending data; Level 2c (OCEBM).
Citation
Wong JMM, Reiffel JA, Kowey PR. Brand-names and higher-cost generics drive avoidable Medicare Part D expenditures: A quantitative analysis using angiotensin-converting enzyme inhibitors and angiotensin receptor blockers as a model. The American Journal of Medicine. 2026;139:50–56. doi:10.1016/j.amjmed.2025.07.020.
Background
Drug spending in Medicare’s prescription drug benefit continues to rise, and brand-name and higher-priced generic choices may add avoidable costs. This study examined recent spending patterns and estimated savings if lower-cost options were used more consistently.
Patients
People enrolled in Medicare’s prescription drug benefit, 2018–2022, who received single-ingredient angiotensin-converting enzyme inhibitors or angiotensin receptor blockers.
Intervention
Modeled substitutions: (1) replace every brand-name fill with its matching generic; (2) replace every fill with the lowest-cost generic within each drug class.
Control
Observed prescribing and spending in Medicare’s public Part D spending dataset.
Outcome
Total spending and estimated avoidable spending (modeled savings).
Follow-up Period
2018–2022 (5 years)
Results
From 2018 to 2022, enrollment grew 13.7%, while total annual spending on these drugs rose modestly (about $1.25 billion to $1.28 billion). Brand-name use was under 1% of fills but accounted for a much larger share of spending, especially for angiotensin receptor blockers.
| Modeled strategy |
Estimated savings |
| Replace all brand-name fills with matching generics (2018–2022 cumulative) |
$429 million |
| Use the lowest-cost generic within each class for all fills (2018–2022 cumulative) |
$2.66 billion |
| Use the lowest-cost generic within each class for all fills (2022 only) |
$457 million |
Limitations
Uses aggregated spending data; no patient outcomes. Assumes drugs are interchangeable. Rebate estimates were indirect and outdated. Excludes combination pills and market price changes from increased demand.
Funding
No specific funding; one author reported minor equity in PRM Pharmaceuticals.
Clinical Application
Prefer generics and consider formulary defaults to the lowest-cost generic in these classes, with clinician opt-out when patient-specific reasons require another drug.
