Deya-Martinez, AngelaRiviere, Jaques GRoxo-Junior, PersioRamakers, JanBloomfield, MarketaGuisado Hernandez, PalomaBlanco Lobo, PilarAbu Jamra, Soraya ReginaEsteve-Sole, AnaKanderova, VeronikaGarcia-Garcia, AnaLopez-Corbeto, MireiaMartinez Pomar, NataliaMartin-Nalda, AndreaAlsina, LaiaNeth, OlafOlbrich, Peter2023-05-032023-05-032022-04-29Deyà-Martínez A, Rivière JG, Roxo-Junior P, Ramakers J, Bloomfield M, Guisado Hernandez P, et al. Impact of JAK Inhibitors in Pediatric Patients with STAT1 Gain of Function (GOF) Mutations-10 Children and Review of the Literature. J Clin Immunol. 2022 Jul;42(5):1071-1082.http://hdl.handle.net/10668/20620Since the first description of gain of function (GOF) mutations in signal transducer and activator of transcription (STAT) 1, more than 300 patients have been described with a broad clinical phenotype including infections and severe immune dysregulation. Whilst Jak inhibitors (JAKinibs) have demonstrated benefits in several reported cases, their indications, dosing, and monitoring remain to be established. A retrospective, multicenter study recruiting pediatric patients with STAT1 GOF under JAKinib treatment was performed and, when applicable, compared with the available reports from the literature. Ten children (median age 8.5 years (3-18), receiving JAKinibs (ruxolitinib (n = 9) and baricitinib (n = 1)) with a median follow-up of 18 months (2-42) from 6 inborn errors of immunity (IEI) reference centers were included. Clinical profile and JAKinib indications in our series were similar to the previously published 14 pediatric patients. 9/10 (our cohort) and 14/14 patients (previous reports) showed partial or complete responses. The median immune deficiency and dysregulation activity scores were 15.99 (5.2-40) pre and 7.55 (3-14.1) under therapy (p = 0.0078). Infection, considered a likely adverse event of JAKinib therapy, was observed in 1/10 patients; JAKinibs were stopped in 3/10 children, due to hepatotoxicity, pre-HSCT, and absence of response. Our study supports the potentially beneficial use of JAKinibs in patients with STAT1 GOF, in line with previously published data. However, consensus regarding their indications and timing, dosing, treatment duration, and monitoring, as well as defining biomarkers to monitor clinical and immunological responses, remains to be determined, in form of international prospective multicenter studies using established IEI registries.enAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/BaricitinibChildrenChronic mucocutaneous candidiasisInborn errors of immunityJAK inhibitorsJAK-STAT pathwayPediatricsPrimary immunodeficiency diseaseRuxolitinibSTAT1 GOFChildGain of Function MutationHumansJanus Kinase InhibitorsMulticenter Studies as TopicRetrospective StudiesSTAT1 Transcription Factorresearch article35486339open accessMonitoreo del AmbienteInfeccionesInhibidores de las Cinasas JanusBiomarcadoresInmunidadEfectos colaterales y reacciones adversas relacionados con medicamentos10.1007/s10875-022-01257-x1573-2592PMC9402491https://link.springer.com/content/pdf/10.1007/s10875-022-01257-x.pdfhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC9402491/pdf