Construct validity, reliability, and threshold value for treatment goals of the Thai version of the 12-item Psoriatic Arthritis Impact of Disease Questionnaire for patients with psoriatic arthritis.

OBJECTIVE: To determine the construct validity, reliability, and treatment goal threshold of a Thai-language version of the 12-item Psoriatic Arthritis Impact of Disease (Thai-PsAID) questionnaire in patients with psoriatic arthritis (PsA). METHODS: This cross-sectional study involved administering the proposed Thai-PsAID to 117 Thai patients with PsA. Reliability was assessed by Cronbach's α test and intraclass correlation coefficient (ICC). Construct validity was assessed using Spearman correlation with clinical disease activity index for psoriatic arthritis (cDAPSA), the Health Assessment Questionnaire (HAQ), EQ-5D index, and the patient-acceptable symptom state (PASS). The optimal cutoff score of the Thai-PsAID for minimal disease activity (MDA) was determined by receiver operating characteristic curves. RESULTS: Participants had a mean age of 49.5 years, 61 (52.1%) were female, and the median disease duration was 5 years. The median Thai-PsAID score was 2.1, with a Cronbach's α coefficient of .95 and an ICC of 0.77. The mean time to complete the Thai-PsAID was 2.1 min, with no missing data. The Thai-PsAID score demonstrated a moderate correlation with the cDAPSA, HAQ, and EQ-5D with indices (Spearman's rho of .64, .54, and -.55, respectively). The cutoff of 2.7 has 81%-84% sensitivity and 69%-85% specificity for classifying patients with MDA, satisfied PASS, and indicating no need to escalate medication. CONCLUSIONS: The Thai-PsAID is a valid, reliable, and feasible tool for measuring PsA prognosis. A cutoff of 2.7 accurately discriminates MDA and PASS and indicates no need for medication escalation. The Thai-PsAID may be used as a standalone measure.

Real world safety of CT-P10 (anti-CD 20 monoclonal antibodies biosimilar) in rheumatic and autoimmune diseases.

BACKGROUND: Rituximab (RTX), anti-CD 20 monoclonal antibodies, has been approved for many rheumatic and autoimmune diseases, the use of RTX is still limited due to financial constrain. Biosimilar RTX may increase access by offering patients a more affordable option, lead to improved patient outcomes. However, real-world data related to its immediate and short-term safety is scarce. This study aimed to evaluate the real-world immediate and short-term safety profiles of CT-P10, a biosimilar of Rituximab, in patients with rheumatic and autoimmune diseases. METHODS: This prospective study included patients diagnosed with rheumatic or autoimmune diseases, aged ≥ 18 years, who were treated with biosimilar RTX at Siriraj or Ramathibodi Hospital during February 2019 to May 2019. Patients were followed up through 6 months after the infusions. RESULTS: Of the 74 patients, with 124 infusions, 84% were females with mean age (SD) of 49.4 (15.7) years. The most common rheumatic and autoimmune disease included in this study was systemic lupus erythematosus (26%). All immediate adverse events (AEs) (15 out of 124 infusions) were mild requiring only symptomatic and supportive treatment. Short-term AEs included infection (N = 35), hematologic abnormalities (N = 33), chylous ascites (N = 1), and others (N = 10). Two deaths were related to serious bacterial and viral infection. Hematologic AEs comprised anemia (N = 5), neutropenia (N = 10), lymphopenia (N = 15), and thrombocytopenia (N = 3). CONCLUSION: In this real-world study, biosimilar RTX (CT-P10) has favorable immediate and short-term safety profiles. However, further studies with large sample size and long-term follow-up in real-world practice are still required to confirm the result.