Limiting radiographic progression is an important long-term goal of treatment of PsA. In a post hoc analysis that included 449 biologic-naive patients with PsA from the DISCOVER-2 trial who received 100 mg guselkumab every 4 or 8 weeks, Mease and colleagues demonstrated that a greater improvement in the Disease Activity Index for PsA (DAPSA) scores as early as week 8 and the achievement of DAPSA low disease activity at week 8 were associated with a significantly lower progression of radiographic joint damage (total PsA-modified van der Heijde-Sharp score) through week 100. Thus, patients who respond well early have better long-term outcomes.
The safety of targeted therapies is always of concern and is inadequately addressed by individual clinical trials. Meta-analyses may provide further insights. In a network meta-analysis of 94 randomized controlled trials that included a total of 54,369 patients with PsA or psoriasis who were treated with 14 biologics, five small molecules, or placebo, Chiu and colleagues found that for patients with psoriasis, infliximab, deucravacitinib, and bimekizumab had the highest risks for infection. In patients with PsA, bimekizumab, apremilast, and 30 mg upadacitinib led to a significantly higher risk for infection compared with placebo, and 30 mg upadacitinib also increasing the risk for serious infection compared with placebo. The risk for infection in patients with PsA did not increase with most bDMARD and targeted synthetic DMARD (tsDMARD), except bimekizumab, apremilast, and 30 mg upadacitinib.
There is increasing recognition of the difficulty in managing patients with refractory PsA. One approach to such difficult-to-treat disease is dual targeted therapy (DTT). However, the safety of these combinations is of major concern. There is currently an ongoing clinical trial comparing a combination of guselkumab and golimumab vs guselkumab alone for treatment-resistant PsA. In the meantime, Valero-Martinez and colleagues have reported results from an observational, retrospective, cross-sectional study that included patients with refractory PsA (n = 14) or spondyloarthritis (n = 22) who simultaneously received two bDMARD or tsDMARD with different therapeutic targets. The most commonly used combinations were a tumor necrosis factor (TNF) inhibitor plus an interleukin (IL)-12/23 pathway inhibitor, followed by a TNF inhibitor plus an IL-17 inhibitor. They found that at a median exposure of 14.86 months, the DTT retention rate in patients with PsA was 42.8%, with 40.0% and 53.3% of patients achieving remission or low activity and major clinical improvements, respectively. Treatment discontinuation due to adverse events was reported in one patient with PsA and multiple comorbidities. Thus, DTT led to satisfactory clinical improvements and no serious adverse events in patients with refractory PsA. The results of larger observational and randomized trials are awaited.