Vinod Chandran, MBBS, MD, DM, PhD
Most research published on psoriatic arthritis (PsA) in the month of June 2021 were related to treatment. Conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and anti-tumour necrosis factor (TNF) remain the most used drugs to treat PsA worldwide. However, the benefits of combining csDMARDs and anti-TNF therapies have been less well studied. Lindström et al studied this question using data from 15,332 patients with PsA from 13 European countries participating in the EuroSpA collaboration who initiated a first anti-TNF treatment in 2006–2017. Sixty-two percent of the patients were on combined therapy, while 38% were no anti-TNF monotherapy. Overall, combined treatment was associated with better remission rates, pooled odds ratio (OR) 1.25 (1.12–1.41). Methotrexate (MTX) comedication was associated with improved rates of remission with adalimumab (OR 1.45 [1.23–1.72]) and infliximab (OR 1.55 [1.21–1.98]) and improved drug retention with infliximab. No effect of comedication could be demonstrated for etanercept. Thus, in clinical practice there may be an advantage to combine MTX with infliximab or adalimumab.
Biosimilars provide similar efficacy and safety to originator biologics at lower cost. Many jurisdictions are mandating nonmedical switch from a biologic to a biosimilar but concerns about such administrative switches remain among patients and physicians. Giunta et al report their observations in patients undergoing nonmedical switch from originator adalimumab to biosimilar adalimumab (ABP 501/ adalimumab-atto). In this retrospective study of 94 patients, 46 of whom underwent nonmedical switch from originator adalimumab to ABP 501, they found no significant differences in PASI or DAS-28 ESR at before and after switch in patients undergoing nonmedical switch from adalimumab originator to ABP 501. This study, although small and observational, adds to the growing body of literature on the effectiveness and safety of biosimilars including nonmedical switching.
About newer therapies, Mease et al reported the 52-week results of the phase 2b trial with tildrakizumab (an anti-IL23 biologic) in PsA. In this study, 391 patients with PsA who were randomly assigned to tildrakizumab 200 mg every 4 weeks (Q4W), tildrakizumab 200 mg, 100 mg, or 20 mg every 12 weeks or placebo Q4W. At week 24, the proportion of patients achieving at least 20% improvement in the American College of Rheumatology response was significantly higher for any dose of tildrakizumab vs placebo (71.4%-79.5% vs 50.6%; all P ≤.0125). However, improvement in dactylitis and enthesitis was not observed. No new safety signals were observed through W52. Tildrakizumab may be another option for the management of PsA but requires further evaluation in phase 3 trials.
About gender differences, Prior-Español et al using the Spanish BIOBADASER III registry demonstrated that women with PsA were at greater risk of discontinuing DMARDs because of both lack of efficacy and adverse events. Finally, Ferguson et al reported results from a prospective, open label study of adults receiving apremilast 30 mg as part of routine care for psoriatic disease. They show that in addition to reduction in disease activity, apremilast treatment was significantly associated with a mean weight loss of 2.2 kg and a mean body mass index decrease of 0.8 kg/m 2 (both P < .001). Improvement in disease activity did not correlate with weight change.