The novel CFAbd-Score.kid(C) reveals a significant decline of abdominal symptoms in children with Cystic fibrosis aged 6 through 11 years on Elexacaftor/Tezacaftor/Ivacaftor -- first results

BackgroundRecently, elexacaftor/tezacaftor/ivacaftor (ETI), the turning point in the course of Cystic fibrosis (CF), was also approved for children with CF (cwCF) aged 6-11years carrying at least one F508del-mutation. Modulating the causative deficiency in the CF transmembrane conductance regulator channel was found to substantially improve the crucially affected respiratory and digestive CF-manifestations. In this regard, for people with CF aged [&ge;]12years, we previously found that ETI decreases significantly abdominal symptoms (AS) using the CFAbd-Score(C). AimsAssessing changes in AS after ETI initiation in cwCF aged 6-11years with the novel pediatric Patient-Reported Outcome Measure CFAbd-Score.kid(C). MethodsThe CFAbd-Score.kid(C), specially developed for cwCF aged <12years, implements pictograms, easy language and children-oriented response strategies, comprising 29 CF-specific gastrointestinal items from five domains. Its scoring algorithm developed following FDA guidelines weights items and domains differently, reaching a maximum of 100 points. CwCF completing at least one questionnaire before ETI initiation and another one during ETI therapy were included. ResultsIn four German CF centers, a total of n=52 cwCF (mean age 8.3{+/-}2.2years) were included, completing a total of n=293 questionnaires. During ETI therapy, significant decreases were observed for mean total CFAbd-Score.kid(C) (-31%/p<0.0001) as well as for mean sub-scores of "pain" (-26%/p<0.01), "QoL impairment" (-48%/p<0.01), "disorders of bowel movement" (-32%/p[&le;]0.0001) and "disorders of appetite" (-42%/p<0.05). ConclusionAmong cwCF aged 6-11years, AS captured with the novel CFAbd-Score.kid(C) significantly decreased during the novel ETI treatment. Simultaneously, CFAbd-Score.kid(C) proved to be sensitive to ETI-induced changes in AS. Further validation steps and international implementation are currently in progress.