Psoriasis Study Examines Cost per Responder with Biologics

Philadelphia, PA—Studies have estimated the cost of biologics needed to achieve an additional responder as measured by the Psoriasis Area and Severity Index (PASI) 75 and PASI 90; however, limited information is available about PASI 100. In a new study, researchers sought to evaluate the cost per additional responder associated with 4 biologics to achieve PASI 75, PASI 90, and PASI 100. The study’s outcomes were presented at the ISPOR meeting during a poster session titled Cost per Additional Responder Associated With Biologic Use in Psoriasis. 

The researchers conducted a literature review to identify randomized, placebo-controlled trials and meta-analyses that included data on PASI 75, PASI 90, or PASI 100 response and associated number needed to treat (NNT) compared to placebo for adalimumab, etanercept, infliximab, and ustekinumab. NNT was calculated as the inverse or absolute risk reduction from placebo. The wholesale acquisition cost for each biologic incurred during the first 12 weeks of treatment were determined using AnalySource data as of November 2014; administration costs were not included. Cost per additional responder was calculated as the NNT multiplied by 12-week drug costs.

Cost per additional responder for PASI 75 was lowest for adalimumab ($18,055-$18,647) and infliximab ($18,101-$19,493) followed by ustekinumab 45 mg ($23,903-$24,516), etanercept ($37,825-$41,036), and ustekinumab 90 mg ($45,048-$48,418). Adalimumab and infliximab also had the lowest cost per responder for PASI 90 ($26,805-$30,418 and $27,569-$30,632, respectively), while etanercept had the higher cost per responder ($84,749-$89,209). Cost per responder for PASI 90 for ustekinumab was $38,785 to $39,532 for 45 mg and $71,095 to $88,256 for 90 mg. The researchers noted that limited data was available on PASI 100; however, cost per additional responder was found to be higher than PASI 75 and PASI 90 based on available data. Cost per additional responder for PASI 100 was $61,769 for adalimumab, $54,302 for etanercept, $122,579 for ustekinumab 45 mg, and $281,011 for ustekinumab 90 mg.

The investigators acknowledged study limitations. The 12-week dosing was based on package inserts for each biologic. Actual dosing may vary in clinical practice due to dose escalations or reductions that may result in significant cost differences. Cost data were based on November 2014 costs and do not reflect any potential price changes since that time. Also, the analysis did not include administration costs, which may impact the overall costs associated with biologics requiring in-office administration such as with infliximab. Finally, costs were based on the first 12 weeks of treatment, which primarily included the induction dosing or both the induction and maintenance phases. Therefore, cost estimates may vary when evaluating annual costs or costs based only on maintenance dosing.

“Understanding the association between costs and NNT across various levels of efficacy may be valuable for decision-makers when evaluating costs for multiple medications with a similar indication,” concluded the researchers.—Eileen Koutnik-Fotopoulos

This study was supported by Eli Lilly and Company.