Study Analyzes Trends in Medicare Spending on Oral Drugs for Chronic Lymphocytic Leukemia From 2014 to 2020
A recent cross-sectional study evaluated Medicare Part D spending on chronic lymphocytic leukemia (CLL) oral treatment drugs, including three Bruton’s tyrosine kinase inhibitors (BTKis) (ibrutinib, acalabrutinib, and venetoclax), two phosphatidylinositol-3 kinase (PI3K) inhibitors (idelalisib and duvelisib), and one B-cell lymphoma-2 inhibitor (venetoclax) from 2014 to 2020 (JAMA Netw Open. 2023 Apr 7;6[4]:e237467. doi:10.1001/jamanetworkopen.2023.7467).
Ibrutinib has been shown to be more effective and safer than previous standard-of-care chemotherapy for treating patients with CLL. Since its approval by the US Food and Drug Administration in 2013, other BTKis and PI3K inhibitors—some of which are less expensive than ibrutinib—have been approved for the treatment of CLL. For their study, Edward R. Scheffer Cliff, MBBS, MPH, Program on Regulation, Therapeutics and Law, Division of Pharmacoepidemiology and Pharmacoeconomics, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, sought to determine whether the availability of these additional drugs would impact the overall costs of the medications and the amount spent on ibrutinib.
Using publicly available data from Medicare Part D, Dr Cliff and colleagues assessed spending on the six CLL drugs, the number of beneficiaries who were prescribed these drugs, and the average amount spent for every 30-day refill. The researchers used SSR Health’s data on 4-quarter rolling average non-Medicaid rebates to estimate the net spending after rebates. They also performed a sensitivity analysis to analyze net price trajectories outside of Medicare.
The study found that there was a significant increase in annual net Medicare spending on the six CLL drugs across all indications from 2014 to 2020—$254 million to $3.7 billion, respectively. In addition, 26, 847 beneficiaries received ibrutinib, an increase from 6,180 in 2014. The net spending for 30-day supplies of ibrutinib in 2020 was $11,890, a 46% increase from $8,206 in 2014. The researchers also found that in 2020, 77% of drug spending was on ibrutinib. Their sensitivity analysis showed that similar increases were evident outside of Medicare.
“Despite increased within-class and between-class competition from drugs with better clinical profiles, both the cost and the rate of prescribing ibrutinib increased markedly,” said Dr Cliff and colleagues.
They noted that several factors may have prevented the brand-to-brand competition from lowering the Medicare drug costs, including payers’ limited ability to use formularies to negotiate prices, financial incentives that can encourage intermediaries to accept high prices, and delays in drug approval due to updated prescriber practices.
The authors acknowledged that the study’s main limitation was that because Medicare does not report spending by indication, they could not determine what portion of the spending is used for CLL rather than other B-cell lymphomas.
Dr Cliff and colleagues suggest that future research should investigate why ibrutinib continues to be the more popular choice among oncologists for CLL treatment when “clinically superior” options are available at similar or lower prices than ibrutinib.
