Longitudinal Trends in Real-World Outcomes after Initiation of Ivacaftor. A Cohort Study from the Cystic Fibrosis Registry of Ireland

Ann Am Thorac Soc. 2019 Feb;16(2):209-216. doi: 10.1513/AnnalsATS.201802-149OC.


Rationale: Patient registries have the potential to collect and analyze high-quality postauthorization data on new medicines.

Objectives: We used cystic fibrosis (CF) registry data to assess outcomes after the initiation of ivacaftor, a CF transmembrane conductance regulator (CFTR) potentiator approved for the treatment of CF with a defective gating CFTR mutation.

Methods: Longitudinal trends were examined using mixed-effects regression analysis in 80 ivacaftor-treated patients with CF aged 6 to 56 years registered with the CF Registry of Ireland with at least 36 months of before and after commencement data. The effects of ivacaftor treatment on forced expiratory volume in 1 second (FEV1) % predicted, body mass index (BMI), hospitalization for pulmonary exacerbation, and oral and intravenous antibiotic use were assessed.

Results: In the 36 months after ivacaftor initiation, FEV1% predicted improved by 2.26% per annum (95% confidence interval [CI], 0.2 to 4.3) for patients aged younger than 12 years, remained unchanged for 12- to younger than 18-year-olds (95% CI, -1.9 to 2.9), and declined in adults by 1.74% per annum (95% CI, -3.1 to -0.4). BMI in adults increased 0.28 kg/m2 per annum (95% CI, 0.03 to 0.5), and there was no significant change in BMI z-score in children (95% CI, -0.01 to 0.1). In the year after ivacaftor initiation, intravenous antibiotic treatment reduced by 46% (95% CI, -62.5% to -23.3%, oral antibiotic treatment reduced by 49% (95% CI, -61.1% to -32.1%), and there was no significant reduction in hospitalization (95% CI, -59.2% to 9.7%).

Conclusions: In this study of real-world CF registry data, clinical outcomes improved and healthcare resource utilization decreased after commencing ivacaftor.

Keywords: modulator; cystic fibrosis; ivacaftor; real-world; registry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aminophenols / therapeutic use*
  • Anti-Bacterial Agents / administration & dosage
  • Body Mass Index
  • Child
  • Cystic Fibrosis / drug therapy*
  • Cystic Fibrosis / genetics
  • Cystic Fibrosis Transmembrane Conductance Regulator / genetics
  • Female
  • Forced Expiratory Volume
  • Genetic Markers
  • Hospitalization / statistics & numerical data
  • Humans
  • Ireland
  • Longitudinal Studies
  • Lung / drug effects*
  • Lung / physiopathology
  • Male
  • Middle Aged
  • Mutation
  • Quinolones / therapeutic use*
  • Registries
  • Respiratory System Agents / therapeutic use*
  • Treatment Outcome
  • Young Adult


  • Aminophenols
  • Anti-Bacterial Agents
  • CFTR protein, human
  • Genetic Markers
  • Quinolones
  • Respiratory System Agents
  • Cystic Fibrosis Transmembrane Conductance Regulator
  • ivacaftor