AUTHOR=Kostik Mikhail M. , Raupov Rinat K. , Suspitsin Evgeny N. , Isupova Eugenia A. , Gaidar Ekaterina V. , Gabrusskaya Tatyana V. , Kaneva Maria A. , Snegireva Ludmila S. , Likhacheva Tatyana S. , Miulkidzhan Rimma S. , Kosmin Artem V. , Tumakova Anastasia V. , Masalova Vera V. , Dubko Margarita F. , Kalashnikova Olga V. , Aksentijevich Ivona , Chasnyk Vyacheslav G. 

TITLE=The Safety and Efficacy of Tofacitinib in 24 Cases of Pediatric Rheumatic Diseases: Single Centre Experience

JOURNAL=Frontiers in Pediatrics

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/pediatrics/articles/10.3389/fped.2022.820586

DOI=10.3389/fped.2022.820586

ISSN=2296-2360

ABSTRACT=JAK-inhibitors are small molecules blocking the JAK-STAT pathway that have proven effective in the treatment of different immune-mediated diseases in adults and juvenile idiopathic arthritis (JIA). 
Aim of study: To evaluate the safety and efficacy of tofacitinib in children with different rheumatic diseases.
Material and methods: We extracted information from 24 children with the following diagnosis: JIA (n=15), undifferentiated systemic autoinflammatory diseases (SAIDs) (n=7), and juvenile dermatomyositis (JDM) (n=2) who have been treated with tofacitinib for a period of longer than six months. The treatment outcomes were classified according to the opinion of the attending physicians as having a complete response (CR), i.e., the absence of disease activity, or a partial response (PR) – a significant improvement of symptoms and disease activity, or no response (NR) - no changes in disease activity. 
Results: CR was achieved in 10/24 patients; 7/15 among JIA patients, 1/2 among JDM patients, 4/7 among SAID patients, and PR in 5/15 of JIA, 1/2 of JDM, and 3/7 of SAID patients. Three non-responders with JIA discontinued tofacitinib. Corticosteroids were successfully tapered off in 11/14 patients and discontinued in 2/14 patients. Four patients had side effects not requiring treatment discontinuation: liver enzyme elevation (n=2), hypercholesterolemia (n=1), lymphadenitis (n=1).
Conclusion:
JAK-inhibitors are effective new therapies for the treatment of multiple immune-mediated diseases. Our experience has shown the best results in patients with JIA and JIA-associated alopecia, and type I interferonopathies. More data from randomized controlled clinical trials are needed to use JAK-inhibitors safely in pediatric rheumatic diseases.