Using elexacaftor/tezacaftor/ivacaftor + ivacaftor in preschool children with cystic fibrosis

In recent years, new drugs have been discovered to treat cystic fibrosis (CF), which directly target the primary defects of CFTR: correctors and potentiators. The aim was to evaluate the efficacy and safety of Trikafta (elexacaftor/tezacaftor/ivacaftor and ivacaftor) in children with CF aged 2 – 6 years in routine clinical practice. Methods. An open observational study enrolled patients diagnosed with CF aged 2 – 6 years (n = 8) who received elexacaftor/tezacaftor/ivacaftor and ivacaftor. The following parameters were evaluated over time: height, weight, body mass index (BMI), sweat chlorides, fecal elastase 1, alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin, and glucose. Results. During therapy, there was an absolute decrease in the level of sweat chlorides from an average of 110.12 (SD – 10.35) mmol/L at visit 1 to 61.37 (SD – 9.15) mmol/L (p < 0.05) after 1 month of treatment. The sweat chlorides level at visit 6 was 52.62 (SD – 7.67) mmol/l (p < 0.05). The body weight increased from 15.5 kg (SD – 2.4) to 18.8 kg (SD – 1.36) (p < 0.05), height – from 99.88 cm to 110.37 cm. The BMI varied from 15.76 (SD – 0.44) kg/m 2 at baseline to 16.26 (SD – 0.23) by the 9 th month (p < 0.05) and 15.02 (SD – 0.13) kg/m 2 by the 12 th month of follow-up (p > 0.05). The level of fecal elastase-1 grew from 143.14 μg/g of stool (SD – 77.12) to 240.3 μg/g of stool (SD – 77.31) at 6 months after the start of therapy, and was 232.7 μg/g of stool (SD – 128.58) by the 12 th month of follow-up (p > 0.05). Undesirable side effects were mild and did not require discontinuation of the drug. Conclusion. For the first time in Russia, an open observational study was conducted as part of routine clinical practice to evaluate the effectiveness and safety of targeted therapy using elexacaftor/tezacaftor/ivacaftor and ivacaftor in children aged 2 – 6 years. Clinical and laboratory efficacy and safety have been demonstrated during 12 months of continuous follow-up.