Treatment
Dr. Ritchlin discussed studies that provide valuable insights for practicing rheumatologists. Regierer et al. evaluated 1,300 patients with PsA given a new biologic or targeted synthetic disease-modifying anti-rheumatic drug (tsDMARD)—some with concomitant methotrexate and others without. Their study showed that only 45% of patients remained on the same biologic DMARD or tsDMARD at 12 months.5 This finding indicates that retention on biologic DMARD or tsDMARD therapy for patients with PsA remains poor and concurrent use of methotrexate may not help.
Other important treatment topics Dr. Ritchlin discussed included how central pain sensitization syndromes are common in patients with PsA and may influence disease activity measures. He also noted that, on average, women with PsA may be less likely to achieve treatment response outcomes even with treat-to-target approaches.
Axial Disease
On the subject of axial disease in PsA, Dr. Ritchlin highlighted similarities and differences found in patients with ankylosing spondylitis.
Jadon et al. performed a prospective cross-sectional study of more than 200 patients with PsA and 200 patients with ankylosing spondylitis in Bath, U.K. They found 43% of patients with radiographic evidence of axial disease had PsA. Among these patients, axial disease was symptomatically silent in 25%. Twenty-four percent of patients with PsA fulfilled the Modified New York criteria for ankylosing spondylitis, and 33% of patients with PsA had spondylitis without sacroiliitis on imaging. Finally, although disease activity, metrology and disability in PsA axial disease were comparable with those with ankylosing spondylitis, radiographic axial disease was more severe in ankylosing spondylitis than PsA.6
These findings provide helpful insights into features that may indicate when and how clinicians can look for spondylitis in patients with PsA.
Remission
Dr. Ritchlin concluded his talk by discussing the potential for using combination therapies to achieve disease remission in PsA. This somewhat radical approach comes from the field of gastroenterology, in which some studies combined medications, such as guselkumab and golimumab, in the treatment of moderate to severe ulcerative colitis. Such work seems to indicate that IL-23 and tumor necrosis factor inhibition may yield synergistic benefit via suppression of pro-inflammatory and increase in anti-inflammatory, gene expression.7
Therapies in the pipeline include anti-IL-17 treatments, such as bimekizumab, sonelokumab and izokibep, and IL-23 inhibition with such agents as tildrakizumab, deucravacitinib and brepocitinib. Janus kinase (JAK) inhibitors may also be a potential treatment for patients with PsA. However, these agents carry a black box warning from the U.S. Food & Drug Administration (FDA) about the potential for increased risk of serious infections, mortality, malignancy, major adverse cardiovascular events and thrombosis. Thus, patient selection for such treatment must be thoughtful.
