PsA: Treatment & Management
BARCELONA—In the world of psoriatic arthritis (PsA), the issue is not a lack of available therapies. Rather, a plethora of options exist within a milieu of uncertainty about which medication to use for each individual patient.
At EULAR 2025, Laura Coates, MBChB, MRCP, PhD, clinician-scientist and senior clinical research fellow at the National Institute for Health Research, University of Oxford, England, guided the audience through this complex topic in her session titled, Psoriatic Arthritis: How to Treat.
Delays in Care
Before delving into specific treatments, Dr. Coates pointed out that delay in diagnosis and undertreatment remain issues in for patients with PsA.
Charlton et al. found that patients with PsA have a longer duration of symptoms before referral to a rheumatologist and initiation of fewer disease-modifying antirheumatic drugs (DMARDs) compared with patients with rheumatoid arthritis (RA), resulting in less improvement in disease activity by three months.1 Additionally, a study from Gossec et al. examined treatment with apremilast vs. placebo in patients with oligoarthritis at baseline. They found that about 35% of patients in the placebo arm and 20% of patients in the apremilast arm progressed to polyarticular disease within four months.2
In Dr. Coates’ view, these data indicate that clinicians must be more vigilant in diagnosing and treating PsA early because the status quo is not ideal.
PsA Management
In managing PsA, clinicians rely on recommendations from several organizations, including the ACR, the National Psoriasis Foundation, the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis and EULAR, which published a 2024 update on its recommendations for the pharmacologic management of psoriatic arthritis.3 Each set of guidelines is evidence-based, but limited in terms of selecting which drug to use at any given time and how to sequence therapy in patients who do not respond to their initial treatment.
Implications of Axial Disease
Dr. Coates noted that a key deciding factor in choosing a patient’s initial treatment is the absence or presence of axial disease. Although much of the evidence is borrowed from literature on axial spondyloarthritis, Dr. Coates identified tumor necrosis factor (TNF) α inhibitors, interleukin (IL) 17 inhibitors and Janus kinase (JAK) inhibitors as treatment options for axial involvement in PsA. She singled out the phase 3 MAXIMISE clinical trial as a well-done study looking at IL-17 inhibitor therapy in patients with PsA and axial involvement.4
In this double-blind study, 497 patients were randomized in a 1:1:1 ratio to receive with 300 mg of subcutaneous secukinumab, 150 mg of subcutaneous secukinumab or placebo weekly for four weeks and then every four weeks thereafter. At week 12, the patients receiving placebo were re-randomized to receive either 300 or 150 mg of secukinumab. At week 12, the percentage of patients who achieved an Assessment of SpondyloArthritis International Society (ASAS) 20 response was 63% in the 300 mg of secukinumab group, 66% in the 150 mg of secukinumab group and 31% in the placebo group. These benefits were sustained by the treatment groups through week 52, and efficacy was observed in patients regardless of prior TNF-α inhibitor exposure.4
Other Initial Treatments
Dr. Coates noted that initial treatment in patients without axial disease need not rely solely on newer, more expensive therapies. Conventional DMARDs, such as methotrexate, leflunomide and sulfasalazine, can be effective in peripheral involvement in PsA.
In the SEAM-PSA clinical trial, methotrexate monotherapy at a dose of 20 mg weekly demonstrated modest efficacy in patients with PsA. However, methotrexate monotherapy was also shown to be significantly less effective than etanercept monotherapy or combination therapy with etanercept and methotrexate.5
In the COMPLETE-PSA clinical trial, combination therapy with methotrexate and leflunomide was found to be more effective than methotrexate alone for PsA. But it was associated with a higher incidence of mild adverse events, such as gastrointestinal symptoms and elevated liver enzymes.6
Also, sulfasalazine demonstrates modest efficacy in the treatment of patients with PsA but is generally less effective than methotrexate monotherapy and combination therapy with methotrexate and leflunomide.7
Treatment Considerations
Dr. Coates provided a helpful summary of considerations for clinicians regarding biologic therapies in patients with PsA.
Often, TNF-α inhibitors are selected as first-line biologic therapy for patients with PsA because we have the most data on these agents, they work for all six domains of disease (i.e., peripheral arthritis, axial disease, enthesitis, dactylitis, skin psoriasis and nail involvement) and they are good at treating symptoms of moderate to severe skin disease. Also, several agents within this class have efficacy for uveitis and inflammatory bowel disease.
The benefits of IL-12/23 inhibitors for patients with PsA include efficacy for skin involvement, applicability for inflammatory bowel disease and less frequent injections. However, these agents do not have evidence that supports their use when a patient has axial involvement.
IL-17 inhibitors are effective for all six domains of disease and—unlike TNF-α inhibitors—can be used in patients with demyelinating diseases, such as multiple sclerosis. However, they should be avoided in patients with inflammatory bowel disease.
IL-23 inhibitors are good for managing severe disease and tend to have a long-lasting, durable treatment response, but have—so far—not been indicated for axial involvement.
Finally, Dr. Coates noted that JAK inhibitors have the benefit of being orally administered, effective for all six domains of disease and can be used in patients with inflammatory bowel disease. However, safety concerns exist regarding the potential of JAK inhibitors to increase the risk of cancer, major adverse cardiovascular events and thrombosis in patients.
Treat to Target
With respect to treatment goals, Dr. Coates stressed the importance of a treat-to-target strategy.
This approach is exemplified by the TICOPA (Tight Control of Psoriatic Arthritis) study, a multi-center, open label, randomized clinical trial of 206 patients with early PsA. In the controlled, parallel group study, patients in the tight-control group were evaluated every four weeks, with therapy escalating if minimal disease activity was not achieved. Meanwhile, the standard-care group was evaluated every 12 weeks and had clinician-guided therapy.8
At week 48, the odds of achieving an ACR20 response were nearly double in the tight-control group compared with the standard-care group. Improvements were also seen across multiple composite disease activity measures in the tight-control group. The study’s intensive approach led to more rapid and sustained disease control, but a higher rate of mild to moderate adverse events was seen in the study.8
In Sum
Dr. Coates’ session covered a great deal of ground, which makes sense in the context of a disease as multi-faceted as PsA. Although we still have a lot to learn about managing this condition, the thoughtful lecture provided insights that can be applied in the clinic here and now.
Jason Liebowitz, MD, FACR, is an assistant professor of medicine in the Division of Rheumatology at Columbia University Vagelos College of Physicians and Surgeons, New York.
References
- Charlton R, Coates L, Galloway J, et al. Diagnostic delay and less intensive therapy for people with psoriatic arthritis compared with rheumatoid arthritis: A nested matched cohort study from within the U.K. National Early Inflammatory Arthritis Audit [abstract 1613]. Arthritis Rheumatol. 2022;74(suppl 9).
- Gossec L, Coates LC, Gladman DD, et al. Treatment of early oligoarticular psoriatic arthritis with apremilast: primary outcomes at week 16 from the FOREMOST randomised controlled trial. Ann Rheum Dis. 2024 Oct 21;83(11):1480–1488.
- Gossec L, Kerschbaumer A, Ferreira RJO, et al. EULAR recommendations for the management of psoriatic arthritis with pharmacological therapies: 2023 update. Ann Rheum Dis. 2024 May 15;83(6):706–719.
- Baraliakos X, Gossec L, Pournara E, et al. Secukinumab in patients with psoriatic arthritis and axial manifestations: Results from the double-blind, randomised, phase 3 MAXIMISE trial. Ann Rheum Dis. 2021 May;80(5):582–590.
- Mease PJ, Gladman DD, Collier DH, et al. Etanercept and methotrexate as monotherapy or in combination for psoriatic arthritis: Primary results from a randomized, controlled phase III trial. Arthritis Rheumatol. 2019 Jul;71(7):1112–1124.
- Mulder MLM, Vriezekolk JE, van Hal TW, et al. Comparing methotrexate monotherapy with methotrexate plus leflunomide combination therapy in psoriatic arthritis (COMPLETE-PsA): A double-blind, placebo-controlled, randomised, trial. Lancet Rheumatol. 2022 Apr;4(4):e252–e261.
- Ritchlin CT, Colbert RA, Gladman DD. Psoriatic arthritis. N Engl J Med. 2017 May 25;376(21):2095–2096.
- Coates LC, Moverley AR, McParland L, et al. Effect of tight control of inflammation in early psoriatic arthritis (TICOPA): A U.K. multicentre, open-label, randomised controlled trial. Lancet. 2015 Dec 19;386(10012):2489–2498.
