Real-world data show that similar treatment outcomes were achieved with ustekinumab and TNF inhibitors in those with psoriatic arthritis.
Psoriatic arthritis (PsA) is a chronic, immune-mediated disease which affects around 22% of those with psoriasis. PsA can present as a combination of axial and peripheral disease with signs including arthritis, enthesitis, dactylitis as well as skin and nail changes. The disease can be treated with non-steroidal anti-inflammatory drugs, synthetic disease-modifying anti-rheumatic drugs but over recent years, there has been an increase in the use of biologic agents. The rational for the use of biologics, arises from evidence implicating a pathological role for the interleukin (IL)-12, and IL23 and IL-17 pathways in the disease. Ustekinumab is an IL-12/23 inhibitor and has been shown to give rise to significant and sustained improvements in the signs and symptoms of PsA. Equally, there is evidence that tumour necrosis factor (TNF) inhibitors are also an effective therapeutic modality, preventing radiographically observed progression of joint destruction in PsA. Nevertheless, an important consideration when deciding to use a biologic agent is which agent is most appropriate. This decision-making is hampered given the absence of head-to-head trials comparing ustekinumab with TNF inhibitors. In trying to compare the relative efficacy of these two treatments, a team from the University of Vienna, Austria, turned to data from the PsABio study. This international, prospective, observational, cohort study, is designed to evaluate the persistence, effectiveness and tolerability of ustekinumab verses TNF inhibitors in patients with PsA. All participants are followed-up biannually for 3 years with an initial analysis of outcomes after 6 months. The outcomes used are the clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA) and Minimal Disease Activity (MDA) or Very Low Disease Activity (VLDA). DAPSA, MDA and VLDA, are considered to be the most useful measures for the assessment of patients with PsA and are based on assessments of several measures including joint tenderness, swelling, and self-reported pain with higher scores reflecting more severe disease. Remission of disease has been defined by a cut-off score of less than 4. Participants were enrolled at 92 sites across Europe and the initial choice of treatment was made at the discretion of the patient’s rheumatologist. Data were collected, from the patient’s medical records, at baseline and then every 6 months.
A total of 868 patients (426 using ustekinumab) were included in the analysis. The mean age of ustekinumab participants was 51.2 years (43% male) whereas the TNF inhibitor participants were significantly younger (mean age 48.5 years, 45.7% male). In addition, disease duration was longer for those using ustekinumab (7.5 vs 6.2 years). Baseline cDAPSA scores were similar (31 vs 29.8, ustekinumab vs TNF inhibitors) and the improvement after 6 months was also similar (-13.7 vs -14.5). Furthermore, cDAPSA remission occurred in 17.5% vs 21.9% (ustekinumab vs TNF inhibitors).
In their discussion the authors commented on how their data clearly shows how both agents had a similar impact on PsA disease activity after only 6 months. They concluded by indicating that future publications will include a longer-term evaluation of the current data.
Smolen JS et al. Effectiveness of IL-12/23 inhibition (ustekinumab) versus tumour necrosis factor inhibition in psoriatic arthritis: observational PsABio study results. Ann Rheum Dis 2021