Efficacy of CFTR modulators in clinical practice (6-month follow-up)

Pathogenetic therapy for the treatment of cystic fibrosis (CF) has been developed that modulates the CFTR protein and restores its activity as a chloride channel. This treatment is represented by CFTR modulators for various genotypes covering 85 - 90% of patients with CF.

The aim was to analyze the efficacy of two targeted drugs in patients aged 6 - 18 years with CF in clinical practice during a 6-month follow-up.

Methods. The study was conducted based on the analysis of the database “CF Patient Registry of the Russian Federation” for 2021 - 2022. The study included 178 patients receiving lumacaftor/ivacaftor and 158 patients receiving elexacaftor/tezacaftor/ivacaftor. Respiratory function indicators (FEV₁, FVC), sweat test, and anthropometric data were analyzed.

Results. In the group of children treated with lumacaftor/ivacaftor, Me (Q1 - Q3) body weight (kg) increased at 6-month follow-up from 40.0 (28.9 - 48.0) to 44.9 (29.3 - 50.8), p < 0.001, and the height (cm) increased from 156.0 (140.0 - 161.0) to 158.0 (143.0 - 162.0),p < 0.001. Me (Q1 - Q3) FEV₁ improved from 63.5 (42.3 - 84.8) to 72.0 (56.9 - 82.4) %,p < 0.045. Sweat test (mmol/l) decreased Me (Q1 - Q3) from 115 (101.0 - 123.0) to 86.5 (79.0 - 103.0), p < 0.001. During therapy with elexacaftor/tezacaftor/ ivacaftor, Me (Q1 - Q3) body weight (kg) increased at 6-month follow-up from 44.4 (36.8 - 50.0) to 49.3 (44.1 - 51.9),p < 0.001, and Me (Q1 -Q3) height (cm) increased from 160.5 (152.3 - 165.1) to 163.0 (155.5 - 166.9),p < 0.001. Me (Q1 - Q3) FVC and FEV₁ improved: FVC from 78.5 (60.9 - 91.0) to 90.5 (76.8 - 106.8) %,p < 0.001, FEV₁ from 73.5 (60.5 - 82.1) to 95.0 (65.3 - 107.0) %,p < 0.001. Sweat test (mmol/l) decreased from 119 (108 - 126) to 75.5 (65.3 - 88);р < 0.001.

Conclusion. Health status indicators of of children with CF aged 6 - 18 years were analyzed for 6 months of targeted therapy (lumacaftor/ivacaftor and elexacaftor/tezacaftor/ivacaftor). Positive changes were observed in weight, height, respiratory function, and sweat test.

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