Study Identifies Risk Factors for Infliximab Discontinuation in RA

All biologic therapies that treat rheumatoid arthritis (RA) and other inflammatory diseases carry the potential for patients to have primary nonresponse, an outcome that leads to discontinuation of the biologic and potentially a switch to a different agent. Such treatment cycling is costly, and it is also associated with reduced efficacy. However, other factors, besides nonresponse, can also be involved in discontinuation.

A study presented at the recent ISPOR 2019 meeting assessed both the cost associated with treatment with infliximab for patients at US hospitals as well as reasons for discontinuation of therapy during follow up, and it found that insurance coverage status is one factor that plays a role in discontinuation of this therapy that rose consistently in price over the study period.

Using the Premier Healthcare Database, researchers identified 4373 patients with RA at 359 US hospitals between 2012 and 2015. All patients had at least 1 infliximab charge, had at least 1 outpatient visit during a 12-month lookback period, and had 2 or more outpatient visits during a 12-month follow-up. Infliximab use was classified as “new start” or “continued” based on whether infliximab was initiated after or before the lookback period, respectively.

In total, 2850 patients were new infliximab starts, and 1523 were continuing infliximab. New starters were more likely to be female, nonwhite, and treated in nonteaching hospitals.

The average infliximab annual cost was estimated to be $18,602 for the overall sample and was higher among continued-treatment patients as well as patients in the Midwest and Northeast. Between 2012 and 2015, the average infliximab cost per patient per year increased by $1066.

New starts discontinued infliximab more frequently (40.5%) than continued users (32.2%). Risk factors for discontinuation included younger age, being a new start, having public or no insurance at index, losing insurance coverage, and having pneumonia during the follow-up period.

Annual infliximab treatment costs are high, concluded the authors, with a 5.7% increase in costs each year, and strong predictors of discontinuation exist. The authors write that clinicians and pharmacists may need to monitor patients who are being treated with infliximab to ensure that they benefit from therapy as much as possible and avoid unnecessary discontinuation.

Reference

Rosenthal N, Wu D, Arsever C, Kartashov A, Baumer D. Infliximab costs and reasons for treatment discontinuation among patients with rheumatoid arthritis receiving treatment in US hospitals—2012-2015. Presented at: International Society for Pharmacoeconomics and Outcomes Research 24th Annual International Meeting; May 18-22, 2019; New Orleans, Louisiana. Abstract PMS11.