Improvement in exercise duration, lung function and well-being in G551D-cystic fibrosis patients: a double-blind, placebo-controlled, randomized, cross-over study with ivacaftor treatment.

G551D, a mutation of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, results in impaired chloride channel function in cystic fibrosis (CF) with multiple end-organ manifestations. The effect of ivacaftor, a CFTR-potentiator, on exercise capacity in CF is unknown. Twenty G551D-CF patients were recruited to a single-centre, double-blind, placebo-controlled, 28-day crossover study of ivacaftor. Variables measured included percentage change from baseline (%Δ) of VO2max (maximal oxygen consumption, primary outcome) during cardiopulmonary exercise testing (CPET), relevant other CPET physiological variables, lung function, body mass index (BMI), sweat chloride and disease-specific health related quality of life (QOL) measures (CFQ-R and Alfred Wellness (AWEscore)). %ΔVO2max was unchanged compared with placebo as was %Δminute ventilation. However, %Δexercise time (mean 7.3, CI 0.5-14,1, P=0.0222) significantly increased as did %ΔFEV1 (11.7%, range 5.3-18.1, P<0·005) and %ΔBMI (1.2%, range 0.1-2.3, P=0·0393) whereas sweat chloride decreased (mean -43.4; range -55.5-18.1 mmol·l-1, P<0·005). Total and activity based domains in both CFQ-R and AWEscore also increased. A positive treatment effect on spirometry, BMI (increased), SCT (decreased) and total and activity based CF-specific QOL measures was expected. However, the lack of discernible improvement in VO2max and VE despite other positive changes including spirometric lung function and exercise time with a 28-day ivacaftor intervention suggests that ventilatory parameters are not the sole driver of change in exercise capacity in this study cohort. Investigation over a more prolonged period may delineate the potential interdependencies of the observed discordances over time. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov-NCT01937325.

Pulmonary and systemic pharmacokinetics of inhaled and intravenous colistin methanesulfonate in cystic fibrosis patients: targeting advantage of inhalational administration.

The purpose of this study was to define the pulmonary and systemic pharmacokinetics of colistin methanesulfonate (CMS) and formed colistin following intravenous (i.v.) and inhaled administration in cystic fibrosis (CF) patients. Six CF subjects were administered nebulized CMS doses of 2 and 4 million IU and an i.v. CMS infusion of 150 mg of colistin base activity. Blood plasma, sputum, and urine samples were collected for 12 to 24 h postdose. To assess the tolerability of the drug, lung function tests, blood serum creatinine concentrations, and adverse effect reports were recorded. All doses were well tolerated in the subjects. The pharmacokinetic parameters for CMS following i.v. delivery were consistent with previously reported values. Sputum concentrations of formed colistin were maintained at <1.0 mg/liter for 12 h postdose. Nebulization of CMS resulted in relatively high sputum concentrations of CMS and formed colistin compared to those resulting from i.v. administration. The systemic availability of CMS was low following nebulization of 2 and 4 million IU (7.93% ± 4.26% and 5.37% ± 1.36%, respectively), and the plasma colistin concentrations were below the limit of quantification. Less than 2 to 3% of the nebulized CMS dose was recovered in the urine samples in 24 h. The therapeutic availability and drug targeting index for CMS and colistin following inhalation compared to i.v. delivery were significantly greater than 1. Inhalation of CMS is an effective means of targeting CMS and formed colistin for delivery to the lungs, as high lung exposure and minimal systemic exposure were achieved in CF subjects.

Lumacaftor/ivacaftor-associated health stabilisation in adults with severe cystic fibrosis.

INTRODUCTION: Lumacaftor/ivacaftor (LUM/IVA) has been shown to improve clinical outcomes in cystic fibrosis (CF) patients homozygous for Phe508del with forced expiratory volume in 1 s (FEV1) % pred >40%. We assessed the clinical utility of LUM/IVA in all eligible adult CF patients with FEV1 % pred <40% treated for at least 1 year under a single-centre managed access programme. METHODS: Following clinical optimisation, eligible patients (n=40) with FEV1 % pred <40% were commenced on LUM/IVA and monitored for tolerance and clinical outcomes, including health service utilisation, pulmonary function, weight and body composition. 24 patients reached 1 year of treatment by the time of evaluation. Six patients discontinued due to adverse events (five for increased airways reactivity) and three underwent lung transplantation. RESULTS: In comparison with the year prior to LUM/IVA commencement, significant reductions (median per year) were observed in the treatment year in the number of pulmonary exacerbations requiring hospitalisation (from 3 to 1.5; p=0.0002), hospitalisation days (from 27 to 17; p=0.0002) and intravenous antibiotic (IVAB) usage days (from 45 to 27; p=0.0007). Mean±sd change in FEV1 % pred was -2.10±1.18% per year in the year prior, with the decline reversed in the year following (+1.45±1.13% per year; p=0.035), although there was significant heterogeneity in individual responses. Mean±sd weight gain at 1 year was 2.5±4.1 kg (p=0.0007), comprising mainly fat mass (mean 2.2 kg). The proportion of patients severely underweight (body mass index <18.5 kg·m-2) decreased from 33% at baseline to 13% at 1 year (p=0.003). CONCLUSION: This real-world evaluation study demonstrated benefits over several clinical domains (infective exacerbations requiring hospitalisation, IVABs, pulmonary function decline and nutritional parameters) in CF patients with severe lung disease.

Body composition and weight changes after ivacaftor treatment in adults with cystic fibrosis carrying the G551 D cystic fibrosis transmembrane conductance regulator mutation: A double-blind, placebo-controlled, randomized, crossover study with open-label extension.

OBJECTIVES: In patients with cystic fibrosis (CF) who carry the G551D mutation, treatment with ivacaftor improves lung function and weight; however, short- and long-term impacts on body composition have not been well studied. METHODS: Twenty adults with CF carrying the G551D mutation (mean ± standard deviation body mass index [BMI] 23.3 ± 4.3 kg/m2) were recruited for a single-center, double-blind, placebo-controlled, 28-d, crossover study of ivacaftor, followed by an open-label extension (OLE) for 5 mo. Eleven patients underwent measurements 2 y later. The study variables included weight, BMI, and body composition (including fat-free mass [FFM] and fat mass). RESULTS: After 28 d of treatment with ivacaftor, weight increased by 1.1 ± 1.3 kg, BMI by 0.4 ± 0.5 kg/m2, and FFM by 1.1 ± 1.2 kg (all P < .005) with no change in fat mass. Differences between 28-d changes on ivacaftor and placebo were not statistically significant. In the following 5 mo of the OLE, there were significant increases in weight (1.2 ± 1.9 kg; P < .05) and fat mass (1.5 ± 1.9 kg; P < .01), but not in FFM. Between baseline and the end of the OLE, the total weight gain was 2.5 ± 2.4 kg (P < .005), comprised of 0.9 ± 1.5 kg FFM (P < .05) and 1.6 ± 1.8 kg fat mass (P < .005). For the 11 participants who were followed for a further 2 y, no further changes in mean weight, BMI, or body composition parameters between 6 mo and 2 y later were observed. CONCLUSIONS: Small gains were seen in FFM in the first month of ivacaftor treatment. Weight, BMI, and fat-mass gains in the first 6 mo on ivacaftor plateaued by 2.5 y. The metabolic and clinical consequences of weight and fat-mass gains remain to be determined.

The AWESCORE, a patient-reported outcome measure: development, feasibility, reliability, validity and responsiveness for adults with cystic fibrosis.

BACKGROUND: Quality of life has improved dramatically over the past two decades in people with cystic fibrosis (CF). Quantification has been enabled by patient-reported outcome measures (PROMs); however, many are lengthy and can be challenging to use in routine clinical practice. We propose a short-form PROM that correlates well with established quality-of-life measures. METHODS: We evaluated the utility of a 10-item score (AWESCORE) by measuring reliability, validity and responsiveness in adults with CF. The questions were developed by thematic analysis of survey questions to patients in a single adult CF centre. Each question was scored using a numerical rating scale 0 to 10. Total scores ranged from 0 to 100. Test-retest reliability was assessed over 24 h. To determine validity, comparisons were sought between stable subjects and those in pulmonary exacerbation, and between AWESCORE and Cystic Fibrosis Questionnaire - Revised (CFQ-R). Responsiveness to pulmonary exacerbation in individual subjects was evaluated. RESULTS: Five domains, each with two questions, were identified for respiratory, physical, nutritional, psychological and general health. A total of 246 consecutive adults attending the outpatient clinic completed the AWESCORE. Scores were higher during clinical stability compared to pulmonary exacerbation (mean± sd): 73±11 versus 48±11 (p<0.001). Each domain scored worse during an acute exacerbation (p<0.001). No differences in reliability were observed in scores on retesting using Bland-Altman comparison. The CFQ-R scores (mean±sd: 813±125) and AWESCORE (81±13) were moderately correlated (Pearson's r=0.649; p=0.002). CONCLUSIONS: The AWESCORE is valid, reliable and responsive to altered health status in CF.

Childbearing concerns, information needs and preferences of women with cystic fibrosis: An online discussion group.

OBJECTIVE: The life expectancy of women with cystic fibrosis (CF) has increased, enabling many to reach reproductive age. However, little is known about the childbearing concerns and information needs of women with CF or their preferences for information about the effect of their condition and its treatment on childbearing. The aim of this study was to identify the childbearing concerns and related information needs and preferences of women with CF. METHODS: To ensure access to a diverse group of women with CF throughout Australia and to minimise the risk of cross infection, an online group was advertised and convened on Facebook from October through December 2017. In a closed-group moderated discussion, participants responded to questions about childbearing concerns and the related information needs and preferences of women with CF. Non-identifiable demographic information was sought via an online anonymous survey. The discussion transcript was analysed thematically. RESULTS: Participants (n = 11) identified a number of concerns about childbearing including uncertainty about whether to have children; achieving or maintaining a pregnancy and giving birth; treatment and treatment adherence during pregnancy, breastfeeding and motherhood; and the impact of pregnancy and childbirth on future health. Women wanted information about childbearing as it related to their CF but reported difficulties accessing up-to-date accurate relevant information. CONCLUSIONS: Women with CF want to be better informed about childbearing, and identified a need for personalised information as well as regular reviews with their CF treating team so that they can make informed decisions about having children.