Updated guidelines for the treatment of psoriatic arthritis

Psoriatic arthritis (PsA) is an autoimmune inflammatory disease. It presents with both joint-related and extra-articular symptoms and manifestations, which can vary from person to person. PsA is often associated with psoriasis, which affects the skin and nails, but can also be associated with inflammation of the intestines and eyes. PsA is also associated with cardiovascular, psychological and metabolic comorbidities, which have a significant impact on quality of life.

However, in recent years, treatment options for this disease have increased significantly, with both pharmacological and non-pharmacological treatments now available.

The EULAR guidelines for the pharmacological treatment of PsA were first written in 2012 and updated in 2015 and 2019. Since then, drugs with new mechanisms of action have become available and a large amount of new long-term data is available on existing drugs.

The updated recommendations include seven general principles, three of which remain unchanged from the last publication and three of which have been restated. One new principle states that treatment selection should take into account safety considerations for individual mechanisms of action to optimize the benefit-risk profile.

There are also 11 individual recommendations: four remain unchanged from the previous version, six have been modified, combined or reformulated, and one is new.

NSAIDs may be offered as first treatment but should not be prescribed alone if there are indications that the disease may be severe.

For people with peripheral arthritis (the majority of people with this disease), prompt initiation of treatment with conventional synthetic disease-modifying antirheumatic drugs (DMARDs), with methotrexate preferred, is recommended. If this strategy fails to achieve the treatment goal, then treatment with a biologic DMARD should be initiated, but there is no preference by drug class for this group of patients.

EULAR also suggests the possibility of using Janus kinase inhibitors after failure of biologic DMARDs or in cases where biologic DMARDs are not suitable. Apremilast may be suggested in specific cases.

An algorithm is also proposed for people with predominantly axial or enthesitic disease. Traditional synthetic DMARDs are not used in these patients; the axial form of the disease responds well to tumor necrosis factor inhibitors (TNFi) or IL-17 inhibitors.

The choice of mechanism of action should take into account extramuscular manifestations, with specific recommendations for people with skin, bowel, or eye involvement.

For example, in people with cutaneous psoriasis, treatment should be directed toward biologic disease-modifying antirheumatic drugs (biologic or bDMARDs) that target interleukins, and there are now four classes to choose from: IL-12/23 inhibitors, IL-23p19 inhibitors, IL-17A, and IL-17A/F inhibitors. People with uveitis should receive monoclonal TNFis, and people with inflammatory bowel disease should use drugs approved for that disease (TNFi, IL-12/23 inhibitor, Janus kinase inhibitor, and in some cases IL-23p19 inhibitor).

In addition to treatment recommendations, the publication also addresses topics such as drug switching and dose reduction for patients in sustained remission. EULAR hopes that these practical and updated recommendations will be useful to both healthcare professionals and their patients, and that they will support access to optimal treatment for people with PsA.

The work was published in the journal Annals of the Rheumatic Diseases.