Electronic monitoring reveals highly variable adherence patterns in patients prescribed ivacaftor
Christopher M Siracusa1, Jamie Ryan2, Lisa Burns1
1Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center (CCHMC), 3333 Burnet Ave, Cincinnati, OH 45202, USA.
Background:
Previous studies of CF treatments have shown suboptimal adherence, though little has been reported regarding adherence patterns to ivacaftor. Electronic monitoring (EM) of adherence is considered a gold standard of measurement.
Methods:
Adherence rates by EM were prospectively obtained and patterns over time were analyzed. EM-derived adherence rates were compared to pharmacy refill history and self-report.
Results:
12 subjects (age 6-48 years; CFTR-G551D mutation) previously prescribed ivacaftor were monitored for a mean of 118 days. Overall adherence by EM was 61% (SD=28%) and decreased over time. Median duration between doses was 16.9 hours (IQR 13.9-24.1 hours) and increased over time. There was no correlation between EM-derived adherence and either refill history (84%, r=0.26, p=0.42) or self-report (100%, r=0.40, p=0.22).
Conclusions:
Despite the promising nature of ivacaftor, our data suggest adherence rates are suboptimal and comparable to other prescribed CF therapies, and more commonly used assessments of adherence may be unreliable.
Related Concept Videos
Drug Accumulation During Multiple Dosing: Intermittent IV Infusions
Therapeutic Drug Monitoring: Affecting Factors
Drug Accumulation During Multiple Dosing: Repetitive IV Injections
Dosage Regimen: Individualization
Therapeutic Drug Monitoring: Drug Analysis Methods
Therapeutic Drug Monitoring: Overview and Classification


