Long-term clinical outcomes of elexacaftor/tezacaftor/ivacaftor therapy in adults with cystic fibrosis and advanced pulmonary disease.

BACKGROUND

The combination of cystic fibrosis transmembrane conductance regulator (CFTR) modulators elexacaftor, tezacaftor and ivacaftor (ELX/TEZ/IVA) has been approved for treatment of cystic fibrosis (CF) patients (pwCF) homozygous and heterozygous for Phe508del. We aim to assess the long-term effects of ELX/TEZ/IVA therapy on clinical outcomes in severe pwCF.

METHODS

Lung function, pulmonary exacerbation (PEx), sweat chloride concentration, body mass index (BMI) and the respiratory domain of the cystic fibrosis questionnaire-revised (CFQ-R RD) were prospectively evaluated in a cohort of pwCF who were candidates for inclusion in a compassionate program of ELX/TEZ/IVA therapy. All procedures were performed at baseline and then at 12 and 24 months after initiation of modulator therapy. The number of PExs in the year before the study enrollment was collected from our records.

RESULTS

Thirty-six adult pwCF (median age 36.7 years; BMI 19.8 kg/m2; FEV1 36.5% predicted) were recruited from 2019. At 12 and 24 months after initiation, the absolute change in ppFEV1 (percent predicted forced expiratory volume in 1 s) from baseline was +12.5% (p < 0.0001) and +13% (p < 0.0001), respectively. A median of 4.0 exacerbations per patient was reported in the preceding year, while the median number of PExs was 0.0 and 1.0 after 12 and 24 months, respectively, of modulator therapy (both p < 0.0001). After 12 and 24 months of ELX/TEZ/IVA therapy, the CFQ-R RD score improved by 22.4 points (p < 0.0001) and 16.7 points (p < 0.0001), and sweat chloride levels decreased by 65.5 mmol/L (p < 0.0001) and 60 mmol/L (p < 0.0001), respectively. BMI significantly increased.

CONCLUSIONS

Long-term ELX/TEZ/IVA combination therapy markedly impacts the clinical status of patients with severe CF, showing a sustained improvement in lung function and PEx rate.