Methotrexate achieves major cDAPSA response, and improvement in dactylitis and functional status in psoriatic arthritis

Objective Despite the widespread clinical use of MTX in PsA, data from published randomized controlled studies suggest limited efficacy. The objective of the present study was to document the efficacy of MTX. Methods This was an open-label, prospective study of patients satisfying the ClASsification criteria for Psoriatic ARthritis study (CASPAR) criteria for PsA who received MTX in doses of ⩾15 mg/week throughout the follow-up period of 9 months. Disease activity was assessed across various domains by tender and swollen joint count, physician and patient global assessment, DAS-28 ESR, Clinical Disease Activity Index for PsA (cDAPSA), Leeds Dactylitis Instrument basic, Leeds Enthesitis Index (LEI), Psoriasis Area and Severity Index (PASI), Minimal Disease Activity and HAQ (CRD Pune version) at baseline and at 3, 6 and 9 months of follow-up. Response to therapy was assessed by EULAR DAS28 ESR, Disease Activity Index for PsA (cDAPSA) response, HAQ response and PASI75. MTX dose escalation and the use of combination DMARDS were dictated by disease activity. Results A total of 73 patients were included, with mean (s.d.) age 44 (9.7) years. The mean (s.d.) dose of MTX used was 17.5 (3.8) mg/week. Seven patients received additional DMARDS (LEF/SSZ). At the end of 9 months, significant improvement (P < 0.05) was noted in the tender joint count, swollen joint count, global activity, DAS-28ESR, cDAPSA, Leeds Dactylitis Index basic, LEI, PASI and HAQ. Major cDAPSA response was achieved in 58.9% of patients. EULAR DAS28 moderate and good response was achieved in 74% and 6.8% of patients, respectively. Minimal Disease Activity was achieved in 63% of patients. A PASI75 response and HAQ response was achieved in 67.9% and 65.8% of patients, respectively. Conclusion MTX initiated at ⩾15 mg/week with targeted escalation resulted in significant improvement in the skin, joint, dactylitis, enthesitis and functional domains of PsA.