Application experience of the Trilexa drug in children aged 6–18 years with cystic fibrosis

CFTR modulators are capable of restoring the function of the CFTR protein, which encodes the chloride channel in cells. A triple therapy containing elexacaftor, tezacaftor (correctors), and ivacaftor (potentiator) has demonstrated the greatest effect. Two drugs containing this combination are registered in the Russian Federation: the original drug Trikafta® and the generic drug Trilexa®.

Objective. To evaluate the efficacy and safety of ivacaftor + tezacaftor + elexacaftor and ivacaftor in children with cystic fi bro- sis in two age groups when switching drugs within the same INN.

Materials and methods. An analysis of the Russian registry (data on targeted therapy) of patients with cystic fibrosis from January 1, 2025, to August 1, 2025 was performed. The efficacy and safety indicators were monitored at the start of therapy (the last day of taking the original drug) and then after 30 and 90 days of taking the generic drug. The study involved 151 patients, who were divided into two age groups: 55 patients aged 6–11 years and 96 adolescent patients aged 12–18 years. The groups were comparable in terms of the key disease indicators.

Results. A significant increase in height and weight was demonstrated in both groups, as well as BMI in the 6–11 year group. In the 12–18 year group, weight and height increased after three months of therapy compared to the start and first month of therapy (weight — p_1–3 = 0.0127), p2–3 =0.007, height — p_1–3 = 0.001, p_2–3 = 0.016). In the 6–11 year old group — weight p_1–2 = 0.009, p_1–3 = 0.004, p_2–3 = 0.009, height p_1–2 = 0.010, p_1–3 = 0.000, p_2–3 = 0.002, BMI p_1–3 = 0.030 p_2–3 = 0.036. Spirometry data achieved with the use of the original drug were high and remained unchanged during 90 days of therapy with the generic drug. Sweat conductivity after one month of therapy increased in the adolescent group (p_1–2 = 0.048), although remaining within the borderline values. Sweat conductivity in the 6–11 year group after one month of therapy decreased, although without a statistically significant difference (p_1–2 = 0.451), remaining within the borderline values. In the 12–18 year group, a decrease in AST was noted after three months of therapy with the generic drug: AST U/l start/last day of taking the original drug — 22.5 (16.8; 29.0), AST U/l after 3 months of taking the generic drug — 21.0 (16.0; 26.0), (p_1–3 = 0.005). A decrease in the total bilirubin (μmol/L) was noted after three months of therapy — 12.25 (9.4; 17.4) compared to the values after one month of therapy with the generic drug — 11.0 (7.9; 16.7), (p_2–3 = 0.017). All parameters were within the reference values. Blood pressure parameters remained unchanged. The incidence of adverse reactions was low, resolved spontaneously, and did not require a dose reduction, temporary or complete discontinuation of the drug.

Conclusion. The conducted study of the efficacy and safety of ivacaftor + tezacaftor + elexacaftor and ivacaftor in children across two age groups after switching medications within the same INN showed that the effect previously obtained with the use of the original drug for more than 12 months is maintained, and the frequency of adverse reactions during therapy with the generic drug does not exceed that when using the original drug. Studies of the efficacy and safety of the generic drug Trilexa® will be continued.

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