According to a Kaiser Family Foundation analysis, 22% of Medicare Part D drug spending in 2021 went towards the 10 top-selling prescription drugs alone.
In 2021, the 10 top-selling prescription drugs under Medicare Part D made up less than 1% of all covered drugs. However, these 10 drugs accounted for 22% of gross Medicare Part D drug spending that year, according to a Kaiser Family Foundation (KFF) analysis.
Total gross spending on all Medicare Part D drugs was $215.7 billion, with $47.7 billion spent on the top 10 drugs alone. With 3566 total drug products covered by Part D that year, the top 100 accounted for 61% of spending. The analysis noted that these numbers do not account for rebates that may have reduced net spending.
All 10 drugs were brand name, with 5 being diabetes drugs. The total gross spending on each drug in 2021 was as follows, in order of least to most spending:
Ozempic (semaglutide injection), Lantus Solostar, Jardiance, Januvia, and Trulicity are all diabetes drugs. Semaglutide is one of multiple glucagon-like peptide-1 (GLP-1) agonists that has gained recent attention as a tool for weight loss. The drug was originally approved in 2017 as Ozempic for the treatment of type 2 diabetes. Semaglutide injection has also been approved for weight loss under the name Wegovy, and in the event of a drug shortage or supply chain issue, patients may be prescribed Ozempic off-label for weight loss.
“While Medicare does not cover Ozempic when prescribed off-label for weight loss due to the current law prohibition on Medicare coverage of drugs when used for weight loss, it is covered as a diabetes drug,” the KFF analysis said, noting that the drug was used by half a million Part D enrollees in 2021.
Among the other 5 drugs, Humira Cf Pen is used to treat rheumatoid arthritis and inflammatory bowel disease, Imbruvica for mantle cell lymphoma, Revlimid for multiple myeloma, and Xarelto and Eliquis are both used as blood thinners.
Additionally, aggregate spending on the top 10 drugs doubled in just 3 years, jumping from $22 billion in 2018 to nearly $48 billion in 2021. The increased spending on these 10 drugs alone accounted for more than half of the increase is overall gross Part D drug spending, which was $166 billion in 2018, and $216 billion and 2021.
When comparing gross spending on each drug between 2018 and 2021, the KFF analysis found that spending on Eliquis increased by 2.5 times, spending on Trulicity more than tripled, and spending on Jardiance increased by more than 5 times.
“For all of these drugs, the percentage increase in gross spending between 2018 and 2021 outpaced the percentage increase in the number of users over these years,” the analysis said.
The new Medicare Drug Price Negotiation Program will initially focus on negotiating prices for 10 Part D drugs in 2026. In the following year, 15 additional Part D drugs will be subject to negotiation, and in 2028, negotiations will extend to 15 more Part D and Part B drugs. For 2029 and later years, negotiations will cover an additional 20 Part D and Part B drugs each year. According to KFF, his gradual approach means that the number of drugs with negotiated prices will increase over time.
“It is important to note that this analysis is not designed to identify which drugs are likely to be subject to price negotiation for 2026, since we do not take into account all of the factors that determine whether a drug is negotiation-eligible and we do not have access to the more current spending data that CMS will use in selecting drugs for price negotiation,” the KFF analysis said.
Still, KFF noted that Trulicity and Ozempic would not be eligible for selection based on their approval dates, which are 2014 and 2017, respectively. Additionally, 3 drugs—Revlimid, Humira, and Lantus—would not be eligible for selection due to the availability of generic or biosimilar versions in 2023.
Cubanski J, Neuman T. A Small Number of Drugs Account for a Large Share of Medicare Part D Spending. KFF website. https://www.kff.org/medicare/issue-brief/a-small-number-of-drugs-account-for-a-large-share-of-medicare-part-d-spending. Published July 12, 2023. Accessed July 13, 2023.