A new study led by researchers at the Johns Hopkins Bloomberg School of Public Health and the American Enterprise Institute finds that insurance denials for first-time prescriptions for brand-name prescription drugs with no generic competitors increased by more than two-thirds between 2018 and 2024.
Researchers analyzed more than 2 million prescription attempts for brand-name drugs with no generic substitutes across commercial insurance, Medicare, Medicaid, and Affordable Care Act marketplace plans.
Overall, the rejection rate among brand name first prescription attempts increased from 24.3% in 2018 to 40.7% in 2024, an increase of 67%. Of the initially rejected fill attempts, 48.4% did not result in a fill for the prescription drug or another drug in the same therapeutic class within 90 days. Patients who were eventually treated filled their prescriptions an average of 12 days after their initial rejection.
Nearly one-third (32%) of first-time fill attempts were denied due to prescription exclusions (medications not covered by the insurance plan) or insurer usage control rules. These rules are intended to control costs and often require prior approval by insurance companies or require patients to try other drugs before receiving the brand-name drug originally prescribed.
Increased use of usage control rules was the biggest factor in brand name prescription drug denials. Commercial insurance plans and Medicaid managed care plans had the steepest increases in utilization management restrictions over the study period.
The study was published online on July 9th. Japan Automobile Manufacturers Association.
We found that insurance restrictions now determine when patients receive their clinician-prescribed medications. Although these policies may help contain drug spending, they can also create significant barriers to timely treatment and increase administrative burden on patients, pharmacists, and clinicians. ”
Dr. Joseph Levy, Assistant Professor, Department of Health Policy and Management, Bloomberg School, and lead author of the study
The findings highlight the trade-off between controlling prescription drug spending and ensuring timely access to treatment. Historically, branded drugs account for a large portion of U.S. drug spending, although they make up a small portion of total prescriptions. According to the Accessible Medicines Association, branded drugs accounted for approximately 10% of total prescriptions and 88% of spending in 2024. This equates to approximately 435 million brand-name prescriptions and a cost of $700 billion. Much of this spending occurs before patents or other market exclusivity allows for generic competition.
In contrast, generic drugs and biosimilars accounted for approximately 90% of prescriptions filled and 12% of prescription drug spending in 2024, with approximately 3.9 billion generic and biosimilar prescriptions and a cost of $98 billion.
In this study, researchers analyzed pharmacy claims data from 1.17 million individuals who attempted to write a single-source branded drug prescription for the first time between January 2018 and September 2024. This study is derived from IQVIA’s Formal Impact Analyzer, a national database of de-identified outpatient pharmacy claims representing all major insurance markets in the United States.
Of the initially refused prescriptions, 39% were eventually filled with the originally prescribed drug within 90 days, and 13% were filled with another drug in the same therapeutic class. Rejection rates varied by treatment class, ranging from initial rejection rates as high as 85% for incretin-based debulking therapies, including GLP-1 receptor agonists and related agents, to 6.7% for oral anticoagulants. GLP-1 and related incretin drugs were among the most common single-source branded drugs in the study.
The study found significant differences by insurance type. Marketplace exchange plans and Medicaid managed care plans had the highest denial rates, with nearly half of first prescription attempts denied, while Medicare plans had the lowest denial rates.
Because coverage barriers were identified at the pharmacy counter, this study captures what happens after a prescription is written, rather than whether it influences a clinician’s initial prescribing decision. Still, the findings suggest that clinicians don’t always know when prescription drugs are removed from a patient’s prescription or require prior authorization before being filled. Researchers note that more real-time information about insurance limits at the point of prescription and a simplified prior authorization process could help reduce delays in treatment.
“As utilization controls become more commonplace, it is important to better understand how these policies impact actual treatment initiation and patient access to medicines,” Levy says.
This study has some limitations. Because the database only includes claims from participating pharmacies, the analysis may miss prescriptions filled elsewhere or through other payment channels. Researchers also were not always able to determine the reason for rejection or determine whether patients received clinically appropriate alternative therapy from another treatment class.
The authors suggest that simplifying and standardizing prior authorization requirements may reduce avoidable pharmacy refusals and treatment delays. However, researchers note that these reforms may come with trade-offs, such as higher drug costs, because prescription management tools can help insurers negotiate discounts and encourage the use of preferred or evidence-based treatments, and if effectively implemented, can encourage more clinically appropriate and cost-effective prescribing.
This research was supported by Arnold Ventures. Levy and co-lead author Benedick Ippolito, a senior fellow at the American Enterprise Institute, were supported by the Johns Hopkins University and American Enterprise Institute Fellowship Exchange Program.
“Formulation-related insurance denials of single-source branded drugs in the United States” was co-authored by Joseph F. Levy, G. Caleb Alexander, Boris Vabson, and Benedic N. Ippolito.
sauce:
Johns Hopkins University Bloomberg School of Public Health
Reference magazines:
Levy, J.F.; others. (2026) Denial of formulation-related insurance for single-source branded drugs in the United States. jam. DOI: 10.1001/jama.2026.8702. https://jamanetwork.com/journals/jama/fullarticle/2851461
