Using a learning health system to understand the mismatch between medicines supply and actual medicines use among adults with cystic fibrosis.

BACKGROUND: Studies in separate cohorts suggest possible discrepancies between inhaled medicines supplied (median 50-60%) and medicines used (median 30-40%). We performed the first study that directly compares CF medicine supply against use to identify the cost of excess medicines supply. METHODS: This cross-sectional study included participants from 12 UK adult centres with ≥1 year of continuous adherence data from data-logging nebulisers. Medicine supply was measured as medication possession ratio (MPR) for a 1-year period from the first suitable supply date. Medicine use was measured as electronic data capture (EDC) adherence over the same period. The cost of excess medicines was calculated as whole excess box(es) supplied after accounting for the discrepancy between EDC adherence and MPR with 20% contingency. RESULTS: Among 275 participants, 133 (48.4%) were females and mean age was 30 years (95% CI 29-31 years). Median EDC adherence was 57% (IQR 23-86%), median MPR was 74% (IQR 46-96%) and the discrepancy between measures was median 14% (IQR 2-29%). Even with 20% contingency, mean potential cost of excess medicines was £1,124 (95% CI £855-1,394), ranging from £183 (95% CI £29-338) for EDC adherence ≥80% to £2,017 (95% CI £1,507-2,526) for EDC adherence <50%. CONCLUSIONS: This study provides a conservative estimate of excess inhaled medicines supply cost among adults with CF in the UK. The excess supply cost was highest among those with lowest EDC adherence, highlighting the importance of adherence support and supplying medicine according to actual use. MPR provides information about medicine supply but over-estimates actual medicine use.

Profile of tezacaftor/ivacaftor combination and its potential in the treatment of cystic fibrosis.

Cystic fibrosis (CF) is a life-limiting autosomal recessive disease caused by dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel. Management of CF has traditionally relied upon managing complications of CFTR protein dysfunction and this has led to a steady improvement in survival of CF patients. However, the landscape of CF care has changed substantially over the last decade with the discovery of CFTR modulators that aim to increase or potentially restore the function of the disease-causing CFTR protein. This narrative review summarizes the development of CFTR therapies so far with emphasis on tezacaftor/ivacaftor combination therapy. We have also summarized the Phase II results of triple combination therapy which promises an effective CFTR modulator therapy for more than 90% of CF patients.

Effect of Ivacaftor on Objective and Subjective Measures of Cough in Patients with Cystic Fibrosis.

BACKGROUND AND OBJECTIVES: Cough is a major symptom in cystic fibrosis. Ivacaftor is a novel drug which targets the G551D mutation and has been demonstrated to improve lung function and weight in the long term. It also improves symptoms of extra-oesophageal reflux. We wanted to evaluate the effect of ivacaftor on cough in cystic fibrosis. METHODS: In two patients with cystic fibrosis the Hull Airway Reflux Questionnaire (HARQ) was completed and objective cough counts were measured prior to and within 4 weeks after initiation of treatment with ivacaftor. Spirometry was also undertaken and weight checked at these time frames. RESULTS: In the first patient the HARQ score decreased from 29 to 11 and objective cough counts from 29 to 9 cough events per hour. Similarly in the second patient the HARQ score decreased from 13 to 9 and objective cough count from 76 to 5 cough events per hour. There was no significant change in spirometric parameters or weight. CONCLUSION: We have observed early subjective and objective improvement in cough measures on treatment with ivacaftor. We suggest that this improvement could be attributed to improvement of gastro-intestinal function and that cough metrics could be used as early and accurate end points of drug efficacy.