Evolution of antiseizure medication use and cost in the United States of America 2006-2021

Trends in anti-seizure medication spending by Medicare Part D and Medicaid from 2012 to 2022

OBJECTIVES

The rising cost of anti-seizure medications (ASMs) in the United States (US) is a major concern for patients, healthcare providers, insurance payors, and policymakers. We aim to describe and analyze the spending trends on ASMs in the Medicare Part D (MPD) and Medicaid population in the US.

METHODS

A retrospective study was conducted on the databases of MPD and Medicaid Spending by Drug from 2012 to 2022, which was published by the Centers for Medicare and Medicaid Services (CMS). The total expenditures (adjusted for inflation to 2022 dollars), number of claims, and cost-per-claim (CPC) for individual ASMs were summarized on an annual basis. Stratifications of ASMs were made by ASM generations and brand versus generic manufacturers.

RESULTS

Expenditure on ASM by both MPD and Medicaid more than doubled between 2012 and 2022, soaring from $2.8 billion to $5.7 billion. The ASMs total annual claim number increased from 32.2 to 43.2 million. In 2012, second-generation ASMs comprised the largest percentage of total spending of MPD (51%) and Medicaid (57%), but third-generation ASMs took over the lead in 2022 (44% of MPD and 68% of Medicaid). The total spending by MPD and Medicaid on brand-name ASMs increased significantly from 2012 to 2022, likely contributed by almost tripling of CPC of brand-name ASMs in 2022. There was no significant change in CPC for generic ASMs from 2012 to 2022.

SIGNIFICANCE

The expenditure by MPD and Medicaid on ASMs has doubled in the past decade. The rise in spending was disproportionately comprised of newer third-generation and brand-name ASMs. Further monitoring of the spending trend and efforts on drug price negotiation may play a role curbing the rising cost of ASMs. The methods to control drug spending remain unclear and drug pricing negotiation and other policy reforms should be considered.

Evolution in the prescription and cost of non-intravenous rescue benzodiazepines for the treatment of seizure emergencies

OBJECTIVE

The proportion of patients with epilepsy who have a non-intravenous rescue benzodiazepine (non-IV-rBZD) available for seizure emergencies is unknown. This study aims to describe prescription patterns from 2006 to 2022, factors associated with prescription, and the impact of recently introduced intranasal benzodiazepines on prescription and cost.

METHODS

Retrospective analysis of the MarketScan Database, a claims database of privately insured patients in the United States.

RESULTS

Among 213 384 patients (53% female, median (p25-p75) age: 33 (17-50) years) with epilepsy taking long-term anti-seizure medications with follow-up of 2.62 (1.54-4.73) years, only 30 371 patients (14.2%) had at least one non-IV-rBZD prescription. The proportion of patients with at least one non-IV-rBZD prescription was higher among: (1) younger patients (61.4% in the 0-5 year age group, 44.2% in the 6-12 year age group, 23.9% in the 13-21 year age group, 4.8% in the 22-35 year age group, 1.8% in the 36-50 year age group, 1.3% in the 51-60 year age group, and 1.0% in the older than 60 years age group); (2) patients with refractory epilepsy (24.3% vs 10.9% in non-refractory epilepsy); and (3) patients with more emergency department visits or hospital admissions for epilepsy (7.1% among patients with 0, 19.2% among patients with 1-3, and 31.1% among patients with more than 3). Multivariate analysis confirmed young age, refractory epilepsy, and emergency department visits or hospitalizations for epilepsy as strong independent predictors of having at least one non-IV-rBZD prescription. Prescriptions for intranasal midazolam and intranasal diazepam have increased rapidly; they had moderately increased the overall proportion of patients with a non-IV-rBZD prescription, whereas the inflation-adjusted cost of non-IV-rBZDs has markedly increased.

SIGNIFICANCE

The vast majority of patients with epilepsy have not filled a prescription for non-IV-rBZDs. Seizure emergency readiness can be markedly improved, especially among adults. The cost of non-IV-rBZDs has increased with intranasal rescue medications.

Pricing dynamics of anti-seizure medications in the U.S

BACKGROUND

The median cost of anti-seizure medications (ASM) in the United States (U.S.) nearly doubled per person between 2006 and 2021. This increase, combined with shifts in ASM usage and the impact of the COVID-19 pandemic on drug supply chains amid rising inflation, underscored the urgent need to scrutinize ASM pricing dynamics. This study aimed to analyze the complex dynamics of ASM pricing in the U.S. over the past decade (2013-2023); this included how the entry of generic ASMs influenced the pricing of brand-name counterparts and what impacted price variations across different ASM formulations (e.g., significant inflation, the COVID-19 pandemic).

METHODS

This study utilized National Average Drug Acquisition Cost (NADAC) data from November 2013 to July 2023. We adjusted ASM prices for inflation using the Consumer Price Index for Medicinal Drugs - Seasonally Adjusted (CPI-MDS). Statistical analyses included fixed effects regressions and multivariable regression analysis to evaluate the impact of inflation, the number of medication labelers, and the COVID-19 pandemic on ASM prices.

RESULTS

Our study analyzed 23 ASMs approved by the U.S. Food and Drug Administration (FDA), which encompassed 223 oral formulations:112 brand-name and 111 generics. From 2013-2016 to 2020-2023, accounting for standard deviations (SD), the average price of brand-name ASMs increased from $8.71 (SD 5.9) to $15.43 (SD 10.7), while generic ASMs saw a slight decrease from $1.39 (SD 1.8) to $1.26 (SD 1.6). Consequently, the price gap between brand-name and generic ASMs surged from 1452.39 % to 3399.26 %. The proportion of matched brand-name and generic ASMs with a price difference of 1000 %-9999 % increased from 32.88 % (2013-2016) to 41.43 % (2020-2023), while those exceeding 10,000 % rose from 16.44 % to 20 % in the same period. Generic immediate-release (IR) formulations were significantly less expensive than extended-release (ER) or delayed-release (DR) counterparts, with cost differences reaching up to 7751.20 %. The number of medication labelers was inversely related to generic ASM prices, which decreased by 5.45 % (p = 0.001) with each additional generic labeler, while brand-name ASM prices increased by 2.46 % (p < 0.001) with each additional generic labeler. The COVID-19 pandemic led to a 24.4 % increase in brand-name ASM prices and a 23.1 % decrease in generic ASM prices.

CONCLUSIONS

The findings reveal an expanding price disparity between brand-name and generic oral ASMs. An inverse relationship was observed between the number of medication labelers and generic ASM prices, with additional labelers driving down generic prices. However, introducing more generic labelers led to a significant increase in brand-name ASM prices. Furthermore, following patent expirations, brand-name ASM prices rose-a trend explained by the "generics paradox," where, contrary to expectations, brand prices do not decrease and may even increase when generics enter the market. These findings underscore the need for targeted interventions in drug pricing policies to manage the rising costs associated with epilepsy treatment. To ensure equitable access to ASMs, stakeholders must understand and address the factors driving these pricing dynamics.

Assessing Clinician Utilization of Next-Generation Antibiotics Against Resistant Gram-Negative Infections in U.S. Hospitals : A Retrospective Cohort Study

BACKGROUND

The U.S. antibiotic market failure has threatened future innovation and supply. Understanding when and why clinicians underutilize recently approved gram-negative antibiotics might help prioritize the patient in future antibiotic development and potential market entry rewards.

OBJECTIVE

To determine use patterns of recently U.S. Food and Drug Administration (FDA)-approved gram-negative antibiotics (ceftazidime-avibactam, ceftolozane-tazobactam, meropenem-vaborbactam, plazomicin, eravacycline, imipenem-relebactam-cilastatin, and cefiderocol) and identify factors associated with their preferential use (over traditional generic agents) in patients with gram-negative infections due to pathogens displaying difficult-to-treat resistance (DTR; that is, resistance to all first-line antibiotics).

DESIGN

Retrospective cohort.

SETTING

619 U.S. hospitals.

PARTICIPANTS

Adult inpatients.

MEASUREMENTS

Quarterly percentage change in antibiotic use was calculated using weighted linear regression. Machine learning selected candidate variables, and mixed models identified factors associated with new (vs. traditional) antibiotic use in DTR infections.

RESULTS

Between quarter 1 of 2016 and quarter 2 of 2021, ceftolozane-tazobactam (approved 2014) and ceftazidime-avibactam (2015) predominated new antibiotic usage whereas subsequently approved gram-negative antibiotics saw relatively sluggish uptake. Among gram-negative infection hospitalizations, 0.7% (2551 [2631 episodes] of 362 142) displayed DTR pathogens. Patients were treated exclusively using traditional agents in 1091 of 2631 DTR episodes (41.5%), including "reserve" antibiotics such as polymyxins, aminoglycosides, and tigecycline in 865 of 1091 episodes (79.3%). Patients with bacteremia and chronic diseases had greater adjusted probabilities and those with do-not-resuscitate status, acute liver failure, and Acinetobacter baumannii complex and other nonpseudomonal nonfermenter pathogens had lower adjusted probabilities of receiving newer (vs. traditional) antibiotics for DTR infections, respectively. Availability of susceptibility testing for new antibiotics increased probability of usage.

LIMITATION

Residual confounding.

CONCLUSION

Despite FDA approval of 7 next-generation gram-negative antibiotics between 2014 and 2019, clinicians still frequently treat resistant gram-negative infections with older, generic antibiotics with suboptimal safety-efficacy profiles. Future antibiotics with innovative mechanisms targeting untapped pathogen niches, widely available susceptibility testing, and evidence demonstrating improved outcomes in resistant infections might enhance utilization.

PRIMARY FUNDING SOURCE

U.S. Food and Drug Administration; NIH Intramural Research Program.