Adverse Events Associated with CFTR Modulator Therapy: Experience from a Tertiary Care Center

This study aimed to evaluate the frequency, nature, and potential factors associated with adverse events associated with cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapy in a pediatric cystic fibrosis (CF) population.

A single-center, retrospective cohort study was conducted at a tertiary care center. Pediatric patients with CF who received CFTR modulator therapy (ivacaftor monotherapy or elexacaftor/tezacaftor/ivacaftor combination) between January 2021 and January 2025 were included. Clinical characteristics and adverse events were analyzed, and patients with and without adverse events were compared.

The study included 100 patients (mean age, 141.5 ± 55.3 months). Adverse events were reported in 24 (24%) patients. Patients experiencing adverse events were significantly older than those who did not (P=.026). The most frequent adverse events were skin rash (33.3%), elevated creatine kinase (20.8%), and gastrointestinal complaints (12.5%). Treatment interruption was required in 12 patients; however, only 1 patient permanently discontinued therapy due to persistent rash and elevated liver enzymes. No severe hepatic or systemic complications occurred.

Cystic fibrosis transmembrane conductance regulator modulators are generally well tolerated in the pediatric population. Most adverse events are mild, transient, and manageable through routine monitoring and temporary cessation, allowing for the safe continuation of therapy.