Experience with the JAK-kinase inhibitor upadacitinib in children with rheumatic diseases
Authors: Alexeeva E.I. ,   National Medical Research Center of Children's Health, Moscow, Russian Federation, Krekhova E.A. , Kriulina T.Yu. , Kriulin I.A. , Dvoryakovskaya T.M. , Isaeva K.B. , Chistyakova E.G. , Chomakhidze A.M. , Lomakina O.L. , Fetisova A.N. , Chibisova K.V. , Tsulukiya I.T. , Shingarova M.Sh. , Botova M.S. , Kondrateva N.M. , Kokina M.Yu. , Rumyantsev M.A. ,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   Association of Pediatric Rheumatologists, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   Association of Pediatric Rheumatologists, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   National Medical Research Center of Children's Health, Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation,   I.M.Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russian Federation
Published: July 2024

The efficacy of JAK-kinase inhibitors in autoimmune diseases is due to the peculiarities of their pathogenesis, the involvement of various cytokines that trigger the cascade of inflammatory reactions, enhance the transcriptional response of disease-induced or disease-associated genes and potentiate the production of proinflammatory cytokines. Only tofacitinib is currently approved for use in pediatric rheumatic diseases. Given the literature data on the efficacy of other JAK-kinase inhibitors in adult rheumatic diseases, we assume the possibility of their use in pediatric patients. Objective. To evaluate the efficacy and safety of selective JAK-kinase inhibitor upadacitinib in children with rheumatic diseases. Patients and methods. Data on 85 pediatric patients with various variants of juvenile idiopathic arthritis (JIA) (n = 64) and systemic connective tissue lesions (SCTL) (n = 21) treated with upadacitinib were included in this retrospective study. Initiation of therapy was carried out on the basis of the rheumatology department of the Research Institute of Pediatric Rheumatology of the Federal State Autonomous Institution "Children's Health Research Center" of the Ministry of Health of Russia (Moscow) in the period from May 2022 to July 2023. Descriptive statistics methods were used to assess the efficacy of upadacitinib therapy, comparative analysis was performed using the Wilcoxon criterion. Therapy outcomes in the group of patients with JIA were evaluated by the percentage of improvement according to pediatric criteria of the American College of Rheumatology, achievement of inactive disease stage according to C.Wallace criteria and JADAS-71 activity index, in the group of patients with SCTL – by the dynamics of clinical and laboratory activity parameters, as well as steroid-saving effect. Results. In patients with JIA without systemic manifestations treated with upadacitinib for 3 months (15/54), 30% improvement in ACR Pedi criteria was recorded in 13/15 (87%), 50% in 12/15 (80%), 70% in 11/15 (73%), and 90% in 10/15 (66%) patients; after 6 months. – 30th; 50th; 70th; 90% improvement in 14/15 (93%), 14/15 (93%), 13/15 (87%), 13/15 (87%) patients, respectively. Inactive disease stage according to C.Wallace criteria after 3 months was achieved in 5/15 (33.3%) patients, after 6 months. – у 11/15 (73,3%). In patients with systemic JIA the efficacy of therapy after 3 months was evaluated in 3/10 patients: 2/3 achieved JADAS remission (1 of them – stage of inactive disease according to C.Wallace criteria), in 1 patient the disease activity increased against the background of hip arthroplasty. After 6 months (assessment of outcomes is available in 3/10 patients): 1 patient achieved JADAS remission, 1 patient achieved 50% improvement according to ACR Pedi criteria, 1 patient showed increased disease activity when attempting to reduce the dose of glucocorticoids (GCS). In the group of patients with SCTL, the majority of patients were able to reduce clinical and laboratory disease activity and the demand for oral GCS. Conclusion. The use of upadacitinib in children in rheumatic diseases is highly effective and safe. In patients with refractory course of the disease it is possible to achieve a decrease in disease activity and remission, to reduce the dose of GCS. Key words: systemic connective tissue lesions, systemic juvenile idiopathic arthritis, upadacitinib, juvenile idiopathic arthritis, Janus kinases