Medicare Part D, also called the Medicare prescription drug benefit, is an optional United States federal-government program to help Medicare beneficiaries pay for self-administered prescription drugs. Part D was enacted as part of the Medicare Modernization Act of 2003 and went into effect on January 1, 2006. Under the program, drug benefits are provided by private insurance plans that receive premiums from both enrollees and the government. Part D plans typically pay most of the cost for prescriptions filled by their enrollees. However, plans are later reimbursed for much of this cost through rebates paid by manufacturers and pharmacies.
Part D enrollees cover a portion of their own drug expenses by paying cost-sharing. The amount of cost-sharing an enrollee pays depends on the retail cost of the filled drug, the rules of their plan, and whether they are eligible for additional Federal income-based subsidies. Prior to 2010, enrollees were required to pay 100% of their retail drug costs during the coverage gap phase, commonly referred to as the "doughnut hole.” Subsequent legislation, including the Affordable Care Act, “closed” the doughnut hole from the perspective of beneficiaries, largely through the creation of a manufacturer discount program.
In 2019, about three-quarters of Medicare enrollees obtained drug coverage through Part D. Program expenditures were $102 billion, which accounted for 12% of Medicare spending. Through the Part D program, Medicare finances about 36% of retail prescription drug spending in the United States.
Program specifics
Eligibility and enrollment To enroll in Part D, Medicare beneficiaries must also be enrolled in either Part A or Part B. Beneficiaries can participate in Part D through a stand-alone prescription drug plan or through a Medicare Advantage plan that includes prescription drug benefits."Medicare: A Primer," Kaiser Family Foundation, April 2010. Beneficiaries can enroll directly through the plan's sponsor or through an intermediary. Medicare beneficiaries who delay enrollment into Part D may be required to pay a late-enrollment penalty. In 2019, 47 million beneficiaries were enrolled in Part D, which represents three-quarters of Medicare beneficiaries.
Plans offered Part D benefits are provided through private plans approved by the federal government. The number of offered plans varies geographically, but a typical enrollee will have dozens of options to choose from. Although plans are restricted by numerous program requirements, plans vary in many ways. Among other factors, enrollees often compare premiums, covered drugs, and cost-sharing policies when selecting a plan.
Medicare offers an interactive online tool that allows for comparison of coverage and costs for all plans in a geographic area. The tool lets users input their own list of medications and then calculates personalized projections of the enrollee's annual costs under each plan option. Plans are required to submit biweekly data updates that Medicare uses to keep this tool updated throughout the year.
In 2021, a new program, the Senior Savings Model, was introduced which was aimed at reducing out-of-pocket costs for insulin.
Costs to beneficiaries
Beneficiary cost sharing
Part D includes a statutorily defined "standard benefit" that is updated on an annual basis. All Part D sponsors must offer a plan that follows the standard benefit. The standard benefit is defined in terms of the benefit structure and without mandating the drugs that must be covered. For example, under the 2020 standard benefit, beneficiaries first pay a 100% coinsurance amount up to a $435 deductible. Second, beneficiaries pay a 25% coinsurance amount up to an Out-of-Pocket Threshold of $6,350. In the final benefit phase, beneficiaries pay the greater of a 5% coinsurance amount or a nominal co-payment amount. These three benefit phases are referred to as the Deductible, Initial Coverage Limit, and the Catastrophic phase.
The "Out-of-Pocket Threshold" is not a cap on out-of-pocket spending, as beneficiaries continue to accrue cost-sharing expenses in the Catastrophic phase. In 2020, beneficiaries would typically reach this threshold as their retail drug spending approached $10,000. When patients enter the Catastrophic phase, the amount they have paid in cost-sharing is typically much less than the Out-of-Pocket Threshold. This is because the standard benefit requires plans to include additional amounts, such as manufacturer discounts, when determining if the Out-of-Pocket Threshold has been met.
Part D sponsors may also offer plans that differ from the standard benefit, provided that these alternative benefit structures do not result in higher average cost-sharing. In practice, most enrollees do not elect for standard benefit plans, instead opting for plans without deductibles and with tiered drug co-payments rather than coinsurance. Enrollees must pay an additional premium amount to be enrolled in a plan with cost-sharing that is lower than the standard benefit, and this additional amount is not Federally-subsidized.
Prior to 2010, the standard benefit included a Coverage Gap phase in which, after accruing significant spending, relatively-high cost enrollees were required to pay a 100% coinsurance amount until they entered the Catastrophic phase. This Coverage Gap phase is commonly referred to as "the Donut Hole." Beginning with the Affordable Care Act, cost-sharing in the Coverage Gap phase has been gradually reduced. Despite no longer triggering elevated cost-sharing, the Coverage Gap phase continues to exist for other administrative purposes.
Beneficiary premiums In 2020, the average monthly Part D premium across all plans was $27.A Data Book: Health Care Spending and the Medicare Program(PDF) . Medicare Payment Advisory Commission. 2020. p. 155. Premiums for stand-alone PDPs are 3 times higher than premiums for MA-PDs, as Medicare Advantage plans often use federal rebates to reduce premiums for drug coverage. Enrollees typically pay their premiums directly to plans, though they may opt to have their premiums automatically deducted from their Social Security checks.
Plans offer competitive premiums to attract enrollees. Premiums must cover the cost of both plan liability and the reinsurance subsidy. From 2017 to 2020, despite rising per capita drug spending, premiums decreased by 16%."Medicare Part D Utilization: Average Annual Gross Drug Costs Per Part D Enrollee, by Type of Plan, Low Income Subsidy (LIS) Eligibility, and Brand/Generic Drug Classification" (PDF) . Centers for Medicare & Medicaid Services. Retrieved July 11, 2021. Plans have been able to lower premiums by negotiating larger rebates from manufacturers and pharmacies. Between 2017 and 2020, the percentage of drug costs rebated back to plans increased from 22% to 28%.2020 Medicare Trustees Report (PDF) . Centers for Medicare & Medicaid Services. 2020. p. 142. In addition, the standard benefit was changed in 2019 to increase mandatory manufacturer discounts in the Coverage Gap.
Part D practices community rating, with all enrollees in a plan being assigned the same premium. Enrollees do pay more in premiums if they enroll in higher-than-average-cost plans or in plans that offer enhanced benefits. Like in Part B, higher-income enrollees are required to pay an additional premium amount. Low-income enrollees may have their premium reduced or eliminated if they qualify for the low-income premium subsidy.
For 2022, costs for stand-alone Part D plans in the 10 major U.S. markets ranged from a low of $6.90-per-month (Dallas and Houston) to as much as $160.20-per-month (San Francisco). A study by the American Association for Medicare Supplement Insurance reported the lowest and highest 2022 Medicare Plan D costs for the top-10 markets.
Retiree drug subsidy (RDS) Retiree Drug Subsidy (RDS) is a program that provides financial assistance to employers who offer prescription drug coverage to their retirees. The subsidy is a feature of Medicare Part D, designed to help retirees access affordable prescription medications.
Low-income subsidies Beneficiaries with income below 150% of the poverty line are eligible for the low-income subsidy, which helps pay for premiums and cost-sharing. Depending on income-level and assets, some beneficiaries qualify for the full low-income subsidy, while others are eligible for a partial subsidy. All low-income subsidy enrollees still pay small copayment amounts.
Low-income enrollees tend to have more chronic conditions than other enrollees. Low-income subsidy enrollees represent about one-quarter of enrollment, but about half of the program's retail drug spending. Nearly 30% of Federal spending on Part D goes towards paying for the low-income subsidy.
In addition to receiving premium and cost-sharing subsidies, certain program rules apply differently for low-income subsidy enrollees. Beneficiaries of the low-income subsidy are exempt from the Coverage Gap Manufacturer Discount Program. Low-income subsidy enrollees are also allowed to change plans more frequently than other enrollees.
Excluded drugs While Centers for Medicare & Medicaid Services (CMS) does not have an established formulary, Part D drug coverage excludes drugs not approved by the Food and Drug Administration, drugs not available by prescription for purchase in the United States, and drugs for which payments would be available under Part B.
Part D coverage excludes drugs or classes of drugs that may be excluded from Medicaid coverage. These may include: Drugs used for anorexia, weight loss, or weight gain Drugs used to promote fertility Drugs used for erectile dysfunction Drugs used for cosmetic purposes (hair growth, etc.) Drugs used for the symptomatic relief of cough and colds Prescription vitamin and mineral products, except prenatal vitamins and fluoride preparations Drugs where the manufacturer requires as a condition of sale any associated tests or monitoring services to be purchased exclusively from that manufacturer or its designee
While these drugs are excluded from basic Part D coverage, drug plans can include them as a supplemental benefit, provided they otherwise meet the definition of a Part D drug. However plans that cover excluded drugs are not allowed to pass on those costs to Medicare, and plans are required to repay CMS if they are found to have billed Medicare in these cases.
Plan formularies Part D plans are not required to pay for all covered Part D drugs. They establish their own formularies, or list of covered drugs for which they will make payment, as long as the formulary and benefit structure are not found by CMS to discourage enrollment by certain Medicare beneficiaries. Part D plans that follow the formulary classes and categories established by the United States Pharmacopoeia will pass the first discrimination test. Plans can change the drugs on their formulary during the course of the year with 60 days' notice to affected parties.
The primary differences between the formularies of different Part D plans relate to the coverage of brand-name drugs. Typically, each Plan's formulary is organized into tiers, and each tier is associated with a set co-pay amount. Most formularies have between 3 and 5 tiers. The lower the tier, the lower the co-pay. For example, Tier 1 might include all of the Plan's preferred generic drugs, and each drug within this tier might have a co-pay of $5 to $10 per prescription. Tier 2 might include the Plan's preferred brand drugs with a co-pay of $40 to $50, while Tier 3 may be reserved for non-preferred brand drugs which are covered by the plan at a higher co-pay, perhaps $70 to $100. Tiers 4 and higher typically contain specialty drugs, which have the highest co-pays because they are generally more expensive. By 2011 in the United States a growing number of Medicare Part D health insurance plans had added the specialty tier.
History