Most Patients With AS Stop Their First Anti-TNF Therapy by Year 2, Study Finds

Ankylosing spondylitis (AS) may be treated with anti—tumor necrosis factor (anti-TNF) agents, but primary treatment failure, loss of response over time, or adverse events can prompt discontinuation. Previous research has also shown that women with AS have lower anti-TNF treatment retention than men with AS. Recently, a new study sought to examine treatment patterns in US patients new to anti-TNF therapy, and it found that a majority of patients, particularly women, do not remain on their first anti-TNF after 2 years.

The observational, retrospective, cross-sectional study was based on data from the IBM MarketScan Research database, which includes deidentified data for more than 50 million covered lives. Adults with AS who had at least 1 claim for an anti-TNF between 2009 and 2013 were included in the cohort.

In total, 1374 patients met the inclusion criteria; 61.7% were male, and the mean age was 43.8 years. Most patients (91.3%) had commercial insurance.

The patients started treatment with adalimumab (44.1%), etanercept (40.9%), infliximab (10.6%), golimumab (4.3%), and certolizumab pegol (0.1%). During the 2-year followup period, only 33.1% of patients were still using their first anti-TNF, whereas 40.7% had discontinued and did not start another anti-TNF and 26.1% switched to a second anti-TNF. Among those who switched, 20.1% went on to switch to a third anti-TNF.

In total, during the 2-year follow-up, 32.6% of men persisted on their first anti-TNF versus 22.8% of women.

Patients who were prescribed conventional disease-modifying antirheumatic drugs were more likely to be persistent on their first anti-TNF. Women and patients treated with opioids were less likely to be persistent on their first anti-TNF and were also more likely to switch to another.

The investigators note that, during the study period, interleukin-17 inhibitors were not available, so it is not possible to know whether switching to such options would have impacted the observed treatment patterns.

More research is needed, they write, to understand the reasons for nonpersistence and the increasing trend of second-line anti-TNF use among patients with AS.

Reference

Hunter T, Schroeder K, Sandoval D, Deodhar A. Persistence, discontinuation, and switching patterns of newly initiated TNF inhibitor therapy in ankylosing spondylitis patients in the United States [published online March 5, 2019]. Rheumatol Ther. doi: 10.1007/s40744-019-0148-4.