Rationale: Ivacaftor (VX-770), a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator, has been shown to improve lung function, pulmonary exacerbation rate, respiratory symptoms, and weight gain compared with placebo in patients with cystic fibrosis aged 12 years or older with a G551D-CFTR mutation. Objectives: This randomized, double-blind, placebo-controlled trial evaluated ivacaftor in patients with cystic fibrosis aged 6–11 years with a G551D-CFTR mutation on at least one allele. Methods: Patients were randomly assigned to receive ivacaftor administered orally at 150 mg (n = 26) or placebo (n = 26) every 12 hours for 48 weeks in addition to existing prescribed cystic fibrosis therapies. Measurements and Main Results: Despite near-normal mean baseline values in FEV1, patients receiving ivacaftor had a significant increase in percent predicted FEV1 from baseline through Week 24 versus placebo group (treatment effect, 12.5 percentage points; P < 0.001). Effects on pulmonary function were evident by 2 weeks, and a significant treatment effect was maintained through Week 48. Patients treated with ivacaftor gained, on average, 2.8 kg more than those receiving placebo at Week 48 (P < 0.001). The change from baseline through Week 48 in the concentration of sweat chloride, a measure of CFTR activity, with ivacaftor was −53.5 mmol/L (P < 0.001) versus placebo. The incidence of adverse events was similar in the two groups. Conclusions: In patients who are younger and healthier than those in previously studied populations, ivacaftor demonstrated a significant improvement in pulmonary function, weight, and CFTR activity compared with placebo. Clinical trial registered with www.clinicaltrials.gov (NCT00909727).

Rationale: Lower airway (LAW) infection with Pseudomonas aeruginosa and Staphylococcus aureus is the leading cause of morbidity in cystic fibrosis (CF). The upper airways (UAW) were shown to be a gateway for acquisition of opportunistic bacteria and to act as a reservoir for them. Therefore, tools for UAW assessment within CF routine care require evaluation. Objectives: The aims of the study were non-invasive assessment of UAW and LAW microbial colonisation, and genotyping of P aeruginosa and S aureus strains from both segments. Methods: 182 patients with CF were evaluated (age 0.4–68 years, median 17 years). LAW specimens were preferably sampled as expectorated sputum and UAW specimens by nasal lavage. P aeruginosa and S aureus isolates were typed by informative single nucleotide polymorphisms (SNPs) or by spa typing, respectively. Results: Of the typable S aureus and P aeruginosa isolates from concomitant UAW- and LAW-positive specimens, 31 of 36 patients were carrying identical S aureus spa types and 23 of 24 patients identical P aeruginosa SNP genotypes in both compartments. Detection of S aureus or P aeruginosa in LAW specimens was associated with a 15- or 88-fold higher likelihood also to identify S aureus or P aeruginosa in a UAW specimen from the same patient. Conclusions: The presence of identical genotypes in UAW and LAW suggests that the UAW play a role as a reservoir of S aureus and P aeruginosa in CF. Nasal lavage appears to be suitable for non-invasive UAW sampling, but further longitudinal analyses and comparison with invasive methods are required. While UAW bacterial colonisation is typically not assessed in regular CF care, the data challenge the need to discuss diagnostic and therapeutic standards for this airway compartment. Trial registration number: NCT00266474.

Abdominal symptoms (AS) are a hallmark of the multiorgan-disease cystic fibrosis (CF). However, the abdominal involvement in CF is insufficiently understood and, compared to the pulmonary manifestation, still receives little scientific attention. Aims were to assess and quantify AS and to relate them to laboratory parameters, clinical findings, and medical history. A total of 131 patients with CF of all ages were assessed with a new CF-specific questionnaire (JenAbdomen-CF score 1.0) on abdominal pain and non-pain symptoms, disorders of appetite, eating, and bowel movements as well as symptom-related quality of life. Results were metrically dimensioned and related to abdominal manifestations, history of surgery, P. aeruginosa and S. aureus colonization, genotype, liver enzymes, antibiotic therapy, lung function, and nutritional status. AS during the preceding 3 months were reported by all of our patients. Most common were lack of appetite (130/131) and loss of taste (119/131) followed by abdominal pain (104/131), flatulence (102/131), and distention (83/131). Significantly increased AS were found in patients with history of rectal prolapse (p = 0.013), distal intestinal obstruction syndrome (p = 0.013), laparotomy (p = 0.022), meconium ileus (p = 0.037), pancreas insufficiency (p = 0.042), or small bowel resection (p = 0.048) as well as in patients who have been intermittently colonized with P. aeruginosa (p = 0.006) compared to patients without history of these events. In contrast, no statistically significant associations were found to CF-associated liver disease, chronic pathogen colonization, lung function, CF-related diabetes, and nutritional status. As the complex abdominal involvement in CF is still not fully understood, the assessment of the common AS is of major interest. In this regard, symptom questionnaires like the herein presented are meaningful and practical tools facilitating a wider understanding of the abdominal symptoms in CF. Furthermore, they render to evaluate possible abdominal effects of novel modulators of the underlying cystic fibrosis transmembrane (conductance) regulator (CFTR) defect.

Introduction: Cystic fibrosis (CF) is a life-shortening condition with no cure. Available therapies relieving the symptoms of CF are complex and time-consuming. A comprehensive review assessing adherence to different CF therapies, association of adherence with outcomes, and factors influencing adherence could inform optimal patient management strategies. Areas covered: A targeted literature review of studies published from 2010–2016 assessed adherence to CF therapies. Nineteen studies qualified for inclusion. Adherence to CF therapies was sub-optimal, and varied by treatment, mode of treatment administration, age, season, time and method of adherence measurement. Adherence to ivacaftor and inhaled antibiotics were reported higher than dornase alfa or hypertonic saline, oral pancreatic enzyme and vitamin supplements, and airway clearance therapy. Several patient, healthcare provider and treatment related factors influenced adherence. Sub-optimal adherence was shown to impact clinical and economic burden of the disease. Expert commentary: Higher adherence to CF therapies can lower disease burden, and improve patient outcomes. Healthcare providers and policy makers should devise patient-centered and caregiver-enabled interventions to improve adherence. Research on long-term adherence and outcomes associated with promising oral treatments such as CFTR modulators is needed. Identifying ways to overcome key barriers to adherence can positively affect outcomes associated with CF.

Background: The novel and highly effective CFTR modulator combination of elexacaftor-tezacaftor-ivacaftor (ETI) has been shown to improve lung function and body weight in people with Cystic Fibrosis (pwCF) carrying a F508del mutation. However, the impact of these modulators on gastrointestinal (GI) symptoms is relatively unknown. Therefore, the CFAbd-Score was developed and validated following FDA recommendations for development of a PROM including focus groups, multidisciplinary CF specialists, people with CF and their families. The aim of this study was to assess effects of ETI on GI symptoms using the CFAbd-Score.Methods: Gastrointestinal symptoms were prospectively assessed in pwCF using the CFAbd-Score before and up to 26 weeks during therapy. The CFAbd-Score was also administered to a healthy control (HC) group. The one-sided questionnaire includes 28 items grouped in five domains. Data analysis included calculation of scores with a weighting tool, developed according to FDA recommendations.Results: A total of 107 pwCF attended in four CF centres in Germany and four centres in the UK completed the CFAbd-Score on at least two occasions. Results were compared to those obtained from the questionnaire of 45 HCs. Despite differences in demographics, age and proportion of pancreatic insufficiency between German and UK patients, analyses based on linear mixed-effects models at week 24 of ETI therapy revealed that estimated marginal means (EMMs) of total CFAbd-Scores significantly reduced (mean ± SE: 14.9 ± 1.2→10.6 ± 1.4; p < 0.01). Also EMMs of all five domains significantly declined (“pain” 16.3 ± 1.6→10.2 ± 2.3, “GERD” 15.8 ± 1.8→8.2 ± 1.9, “disorders of bowel movement” 20.9 ± 1.5→16.0 ± 1.7, “disorders of appetite” 7.9 ± 1.1→2.6 ± 1.1 and “quality of life impairment” 10.1 ± 1.92→3.9 ± 1.9). However, during 24 weeks, CF participants’ symptoms mostly still did not reach the reference levels of HCs.Discussion: Using the CFAbd-Score, the first PROM specifically developed for assessment of CF-related abdominal symptoms, we demonstrate comprehensive improvements in GI symptoms after initiation of the highly effective modulator therapy ETI.

Staphylococcus aureus is an important pathogen in cystic fibrosis (CF). However, it is not clear which factors are associated with worse lung function in patients with persistent S. aureus airway cultures. Our main hypothesis was that patients with high S. aureus density in their respiratory specimens would more likely experience worsening of their lung disease than patients with low bacterial loads. Therefore, we conducted an observational prospective longitudinal multi-center study and assessed the association between lung function and S. aureus bacterial density in respiratory samples, co-infection with other CF-pathogens, nasal S. aureus carriage, clinical status, antibiotic therapy, IL-6- and IgG-levels against S. aureus virulence factors. 195 patients from 17 centers were followed; each patient had an average of 7 visits. Data were analyzed using descriptive statistics and generalized linear mixed models. Our main hypothesis was only supported for patients providing throat specimens indicating that patients with higher density experienced a steeper lung function decline (p<0.001). Patients with exacerbations (n = 60), S. aureus small-colony variants (SCVs, n = 84) and co-infection with Stenotrophomonas maltophilia (n = 44) had worse lung function (p = 0.0068; p = 0.0011; p = 0.0103). Patients with SCVs were older (p = 0.0066) and more often treated with trimethoprim/sulfamethoxazole (p = 0.0078). IL-6 levels positively correlated with decreased lung function (p<0.001), S. aureus density in sputa (p = 0.0016), SCVs (p = 0.0209), exacerbations (p = 0.0041) and co-infections with S. maltophilia (p = 0.0195) or A. fumigatus (p = 0.0496). In CF-patients with chronic S. aureus cultures, independent risk factors for worse lung function are high bacterial density in throat cultures, exacerbations, elevated IL-6 levels, presence of S. aureus SCVs and co-infection with S. maltophilia. ClinicalTrials.gov NCT00669760