Prospective study to characterize adalimumab exposure in pediatric patients with rheumatic diseases.

BACKGROUND: In pediatric rheumatic diseases (PRD), adalimumab is dosed using fixed weight-based bands irrespective of methotrexate co-treatment, disease activity (DA) or other factors that might influence adalimumab pharmacokinetics (PK). In rheumatoid arthritis (RA) adalimumab exposure between 2-8 mg/L is associated with clinical response. PRD data on adalimumab is scarce. Therefore, this study aimed to analyze adalimumab PK and its variability in PRD treated with/without methotrexate. METHODS: A two-center prospective study in PRD patients aged 2-18 years treated with adalimumab and methotrexate (GA-M) or adalimumab alone (GA) for ≥ 12 weeks was performed. Adalimumab concentrations were collected 1-9 (maximum concentration; Cmax), and 10-14 days (minimum concentration; Cmin) during ≥ 12 weeks following adalimumab start. Concentrations were analyzed with enzyme-linked immunosorbent assay (lower limit of quantification: 0.5 mg/L). Log-normalized Cmin were compared between GA-M and GA using a standard t-test. RESULTS: Twenty-eight patients (14 per group), diagnosed with juvenile idiopathic arthritis (71.4%), non-infectious uveitis (25%) or chronic recurrent multifocal osteomyelitis (3.6%) completed the study. GA-M included more females (71.4%; GA 35.7%, p = 0.13). At first study visit, children in GA-M had a slightly longer exposure to adalimumab (17.8 months [IQR 9.6, 21.6]) compared to GA (15.8 months [IQR 8.5, 30.8], p = 0.8). Adalimumab dosing was similar between both groups (median dose 40 mg every 14 days) and observed DA was low. Children in GA-M had a 27% higher median overall exposure compared to GA, although median Cmin adalimumab values were statistically not different (p = 0.3). Cmin values ≥ 8 mg/L (upper limit RA) were more frequently observed in GA-M versus GA (79% versus 64%). Overall, a wide range of Cmin values was observed in PRD (0.5 to 26 mg/L). CONCLUSION: This study revealed a high heterogeneity in adalimumab exposure in PRD. Adalimumab exposure tended to be higher with methotrexate co-treatment compared to adalimumab monotherapy although differences were not statistically significant. Most children showed adalimumab exposure exceeding those reported for RA with clinical response, particularly with methotrexate co-treatment. This highlights the need of further investigations to establish model-based personalized treatment strategies in PRD to avoid under- and overexposure. TRIAL REGISTRATION: NCT04042792 , registered 02.08.2019.

Living with autoinflammatory diseases: identifying unmet needs of children, adolescents and adults.

BACKGROUND: Autoinflammatory diseases (AIDs) illnesses of the innate immunity resulting in clinical signs and symptoms of systemic inflammation and loss of organ functions. While pathophysiological mechanisms are heavily studied and increasingly well understood, psychosocial needs are much less explored. The disease impact on the everyday life of patients including school and work is poorly studied. The purpose of the study was to identify the spectrum of unmet needs of children, adolescents and adults living with autoinflammatory disease and their families, to define key unmet needs and strategies and to develop and evaluate a pilot intervention addressing the unmet need "school". METHODS: A single-center, mixed-method study of AID patients and their families was conducted. Consecutive patients ages ≥4 years and their families were included. Expert consulting, focus groups and questionnaires explored the patient perspective of "unmet needs in AID". Quantitative and qualitative content analyses were performed and informed the development of a framework of unmet needs. A targeted pilot multimodular intervention for the unmet need "school" was developed and tested. Health-related Quality of Life (HRQoL) was evaluated using DISABKIDS-questionnaires and psychosocial impact evaluations. RESULTS: The study included 83 patients and their families. These were 14 children, 9 adolescents and 25 adults with AID and 35 family members; patients' median age was 19 years (5-78). Expert consultations: 110 AID patients with 320 visits/year; 99 (90%) were children and adolescents. 78 patients and family members (94%) participated in 10 groups. Qualitative content analysis delineated 9 domains of unmet needs, the most relevant being school, health care system and public institutions. The pilot intervention"school" included 18 participants; median age was 9 years (7-16). HRQoL improved with the intervention including "understanding" by 53%, however improvement was not sustained over time. CONCLUSION: Unmet needs of AID patients and families affect all areas of life. Accessible networks increasing knowledge and empowering patients, strategies supporting academic and workplace environments to ensure successful participation and integrated concepts addressing psychosocial needs are urgently needed.