The average cost of biologic treatments for plaque psoriasis more than doubled over a 14-year period, according to a comprehensive analysis published in JAMA Dermatology. Researchers found that as prescribing patterns shifted toward newer interleukin inhibitors, annual treatment costs rose substantially despite the availability of lower-cost alternatives.
The cross-sectional study, led by Benjamin N. Rome, MD, MPH, from Brigham and Women's Hospital and Harvard Medical School, examined data from 76,781 commercially insured patients who initiated first-line biologic therapy for plaque psoriasis between 2007 and 2021.
Dramatic Shift in Prescribing Patterns
The analysis revealed a significant transition in treatment preferences over the study period. By 2021, newer interleukin inhibitors had largely displaced tumor necrosis factor-alpha (TNF-α) inhibitors as first-line therapy options. Specifically, 42% of patients initiated treatment with an IL-23 inhibitor and 21% with an IL-17 inhibitor.
This shift coincided with the rising costs of biologic treatments, which increased from an average of $21,236 in 2007 to $47,125 in 2021. The researchers noted substantial price variations among available biologics, with 2021 costs ranging from $12,413 for infliximab to $70,043 for risankizumab.
"This shift from older treatments to newer ones has had major cost consequences and is poised to contribute to even greater variations in cost, especially if patients continue with these newer options even after biosimilar competition results in lower prices for older treatments," the researchers wrote.
Significant Cost-Saving Opportunities
Perhaps most striking was the researchers' finding that if patients had been prescribed the lowest-cost biologic within each drug class, the average annual treatment cost in 2021 would have been 44% lower—approximately $26,363 instead of $47,125.
The study identified several patient characteristics associated with a higher likelihood of receiving an IL inhibitor rather than a TNF-α inhibitor. These included:
- Older age
- Male gender
- Residence in the northeastern United States
- Absence of comorbid inflammatory arthritis or inflammatory bowel disease
Study Population and Methodology
The study population was evenly distributed between men (49.6%) and women (50.4%), with most patients (71.8%) between 30 and 59 years of age. Approximately 30% had a concurrent diagnosis of inflammatory arthritis.
Researchers utilized the Merative MarketScan database to identify biologic-naive patients with plaque psoriasis. The analysis focused on 11 FDA-approved biologics identified in the 2019 American Academy of Dermatology-National Psoriasis Foundation treatment guidelines, including:
- Four TNF-α inhibitors (certolizumab, adalimumab, etanercept, and infliximab)
- One IL-12/23 inhibitor (ustekinumab)
- Three IL-17 inhibitors (secukinumab, brodalumab, ixekizumab)
- Three IL-23 inhibitors (tildrakizumab, guselkumab, risankizumab)
The study also included three infliximab biosimilars marketed in the US by 2021.
Implications for Healthcare Costs and Access
The rising costs of biologic treatments have significant implications for healthcare systems and patient access. As the researchers noted, payers often limit coverage for psoriasis biologics to patients with severe disease due to cost concerns, creating challenges for both patients and clinicians.
"Due to variations in pricing among drugs, there could be substantial savings if patients initiate the lowest-cost medication in each class and/or if payers negotiate value-based prices that match the lowest price in a drug class," the researchers concluded.
Study Limitations
The researchers acknowledged several limitations to their analysis. The study focused on net health system costs without accounting for patients' out-of-pocket expenses. Additionally, while net prices were based on average rebate estimates, actual drug costs vary by insurer. The analysis was also limited to first-line biologic use and did not assess treatment changes due to ineffectiveness or side effects.
Despite these limitations, the findings highlight important trends in the treatment of plaque psoriasis and suggest opportunities for more cost-effective prescribing practices that could help maintain access to these transformative therapies while controlling healthcare expenditures.
