For a study, researchers determined that Elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) was demonstrated to be effective and safe in patients aged 12 and above who have cystic fibrosis and at least one F508del-CFTR (cystic fibrosis transmembrane conductance regulator) allele, but it has not been tested in children under the age of 12. In children aged 6 to 11 years old with F508del–minimal function or F508del-F508del genotypes, the safety, pharmacokinetics, and effectiveness of ELX/TEZ/IVA were evaluated by researchers. Children weighing less than 30 kg received half of the ELX/TEZ/IVA adult daily dose (ELX 100 mg once daily, TEZ 50 mg once daily, and IVA 75 mg every 12 h) in this 24-week open-label phase 3 study, whereas children weighing more than 30 kg received the full adult daily dose (ELX 100 mg once daily, TEZ 50 mg once daily, and IVA 75 mg every 12 h) (ELX 200 mg once daily, TEZ 100 mg once daily, and IVA 150 mg every 12 h). The primary outcome was tolerability and safety. The safety and pharmacokinetic characteristics of ELX/TEZ/IVA were similar to those seen in elderly patients. Cough, headache, and pyrexia were the most commonly reported side effects, which were mild to moderate in intensity in the majority of the children who had them.

ELX/TEZ/IVA treatment improved the percentage of predicted FEV1 (10.2%age points; 95% CI, 7.9 to 12.6), the Cystic Fibrosis Questionnaire-Revised respiratory domain score (7.0 points; 95% CI, 4.7 to 9.2), lung clearance index 2.5 (1.71 units; 95% CI, 2.11 to 1.30), and sweat chloride (60.9 mmol/L; 95% CI, 63.7 to 58.2) through the findings suggest that ELX/TEZ/IVA is safe and effective in children aged 6 to 11 with at least one F508del-CFTR allele, indicating that it can be used in this patient population.