musculoskeletal and connective tissue disorders
Psoriatic Arthritis
Treatment of Psoriatic Arthritis
Arthritis treated with disease-modifying antirheumatic drugs (DMARDs—particularlymethotrexate),apremilast, and biologic agents (tumor necrosis factor [TNF]-alpha antagonists,ustekinumab,secukinumab,ixekizumab,tofacitinib,abatacept, andguselkumab) For axial disease, biologic agents such as tumor necrosis factor [TNF]-alpha antagonists,secukinumab,ixekizumab, Janus kinase (JAK) inhibitors, and consideration of the IL-12/23 inhibitorustekinumab Treatment of psoriatic arthritis is directed at Treatment and at reducing joint inflammation. A treat-to-target approach to achieve full disease remission or minimal disease activity has been suggested and can be assessed at each visit by using the disease activity index for psoriatic arthritis (DAPSA) or minimal disease activity (MDA) scores ( Drug therapy has been similar to that for Rheumatoid Arthritis (RA) , particularly using the Methotrexate10 to 15 mg orally once/week (withfolic acid1 mg orally once/day) is given. If tolerated but not adequate, the dosage ofmethotrexateis increased after 3- to 5-week intervals to a maximum of 25 mg orally or by injection once/week (oral bioavailability decreases above 15 mg in a single dose). In some patients, skin is more responsive than the joints tomethotrexate. Sulfasalazineis usually given as enteric-coated tablets. Benefit should occur within 3 months. Enteric coating or dose reduction may increase tolerability. Because neutropenia may occur early, complete blood count (CBC) should be obtained after 1 to 2 weeks and then about every 12 weeks during therapy. Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) should be obtained at about 6-month intervals and whenever the dose is increased. Response has been inconsistent. Apremilastis a phosphodiesterase-4 inhibitor that is effective for psoriasis and psoriatic arthritis. The initial dosage is 10 mg orally once/day, titrated to the maintenance dose of 30 mg orally twice a day as tolerated. Adverse effects include diarrhea, nausea, headache, depression, and weight loss. Skin is often more responsive to this medication than the joints. , and their biosimilars) reduce the progression of joint damage (see Treatment for more details about TNF inhibitors). TNF inhibitors occasionally paradoxically trigger psoriaform reactions including plaque, palmoplantar pustular, and guttate psoriasis. is an interleukin (IL)-12 and IL-23 antagonist. The dosage is 45 mg subcutaneously at weeks 0 and 4 (loading dosages) followed by 45 mg every 12 weeks thereafter. The dosage is 90 mg subcutaneously if the patient weighs > 100 kg. Adverse effects are similar to those of the other Biologic agents . Guselkumabis an anti-IL-23-specific monoclonal antibody that is effective in treating moderate to severe psoriasis and has shown to be effective in treating psoriatic arthritis as well. It is given by subcutaneous injections at a recommended dose of 100 mg at weeks 0 and 4 and every 8 weeks thereafter. Secukinumabis an IL-17 inhibitor.Secukinumabcan be given at a dosage of 150 mg subcutaneously at weeks 0, 1, 2, 3, and 4 and every 4 weeks thereafter. Without the loading (weekly) dosage,secukinumabis given at 150 mg subcutaneously every 4 weeks. ​If patients continue to have active psoriatic arthritis, a dose of 300 mg should be considered. ​Secukinumabmay be given with or withoutmethotrexate. Adverse effects include urticaria, upper respiratory infections, fungal infections due toCandida,diarrhea, herpes zoster, and worsening inflammatory bowel disease. Ixekizumabis an IL-17A inhibitor. It is indicated for adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy as well as for adults with active psoriatic arthritis. It may be given alone or in combination with a conventional DMARD (eg,methotrexate). The dosage is 160 mg subcutaneously (two 80-mg injections) at week 0, followed by 80 mg subcutaneously every 4 weeks.Ixekizumabincreases the risk of upper respiratory infections and fungal infections and has also been associated with worsening symptoms of inflammatory bowel disease. or other DMARDs. The dosage is 5 mg orally 2 times a day. The extended-release dosage is 11 mg orally once/day. Potential adverse effects include risk of infection, particularly varicella-zoster virus reactivation, increased creatinine levels, neutropenia, venous thromboembolic events, and hyperlipidemia. See Treatment for more details about major cardiovascular adverse events and malignancies with JAK inhibitors ( Abataceptis a soluble fusion cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) Ig. It is available for adults with active psoriatic arthritis and can be used with or without a nonbiologic DMARD (eg,methotrexate,sulfasalazine,hydroxychloroquine,leflunomide). It may be given as an IV infusion or as a subcutaneous injection. For the IV infusion, the dose is weight adjusted as follows: 500 mg for patients weighing < 60 kg, 750 mg for patients weighing 60 to 100 kg, and 1 g for patients weighing > 100 kg. After the initial dosage,abataceptshould be given at weeks 2 and 4 and every 4 weeks thereafter. The subcutaneous injection dosage is 125 mg once/week. Adverse effects include pulmonary toxicity, susceptibility to infection, headache, upper respiratory infection, sore throat, and nausea. 1.Schoels MM, Aletaha D, Smolen JS: Defining remission and treatment success using the DAPSA score: response to letter by Helliwell and Coates.Ann Rheum Dis74(12):e67, 2015. doi:10.1136/annrheumdis-2015-208521 2.Coates LC, Helliwell PS: Validation of minimal disease activity criteria for psoriatic arthritis using interventional trial data.Arthritis Care Res (Hoboken)62(7):965-969, 2010. doi:10.1002/acr.20155 3.Ytterberg SR, Bhatt DL, Mikuls TR, et al: Cardiovascular and cancer risk withtofacitinibin rheumatoid arthritis.N Engl J Med386(4):316-326, 2022. doi:10.1056/NEJMoa2109927 