Cystic fibrosis drug trial design in the era of CFTR modulators associated with substantial clinical benefit: stakeholders' consensus view.

CFTR modulators associated with substantial clinical benefit are expected to rapidly improve the baseline condition of people with cystic fibrosis (PWCF) as well as decrease the rate of lung function decline, the occurrence of pulmonary exacerbations and likely even other disease complications. These changes in clinical status of PWCF introduced by clinically effective modulator therapy will have major repercussions on modalities of future CF drug development. As part of its 'Strategic Plan to speed up Access to new Drugs', the European Cystic Fibrosis Society (ECFS) convened a meeting in Brussels on November 27th 2019 with relevant stakeholders (CF researchers and clinicians, patient organization and pharmaceutical company representatives, regulators, health technology assessors; see Acknowledgments for list of attendees) to discuss the future of clinical trials in cystic fibrosis (CF) in the context of HEMT entering the clinical arena. The following is the conclusion of the presentations and discussions. It is hoped that these concepts will be considered in future regulatory guidelines and may provide rationale and support for alternative trial designs.

Building global development strategies for cf therapeutics during a transitional cftr modulator era.

As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development.

A critical review of definitions used to describe Pseudomonas aeruginosa microbiological status in patients with cystic fibrosis for application in clinical trials.

BACKGROUND: Definition of Pseudomonas aeruginosa (Pa) microbiological status is essential for patients' inclusion in clinical trials. The aim of this study was to agree on the definitions of Pa infection status for initial infection, eradication and chronic infection to be used in clinical trials and to propose additional future study areas. METHODS: An exhaustive literature search was performed. The clinimetric properties of different definitions of Pa microbiological status were evaluated. RESULTS: Historical studies have mostly used culture-based definitions, although some have also involved complementary anti-Pa antibodies. Clinimetric analysis showed great variability in the definitions used, leading to differences in reliability, validity, responsiveness to treatment and correlation with outcome measures. Use of serology for initial Pa infection and successful Pa eradication introduced a greater level of complexity as antibody tests are not standardised. Moreover, the chronology of the immune response to Pa antigenic determinants was not completely clear. Chronic Pa infection was characterized by high levels of antibodies and good concordance between culture results and serology. CONCLUSIONS: Microbiological monitoring, regular sampling from the airways and standardization of culture methods remain essential requisites for microbiological definitions. Despite limitations, serology should be incorporated in the definitions of initial infection and eradication used in clinical trials to better classify patients at enrolment, mainly in non-expectorating children. This requires standardization of serological testing.

How and why to monitor Pseudomonas aeruginosa infections in the long term at a cystic fibrosis centre.

BACKGROUND: Pseudomonas aeruginosa is a major cystic fibrosis (CF) pathogen causing chronic respiratory infections and posing a risk for cross-infection between patients with CF. AIM: To propose an algorithm for long-term surveillance of P. aeruginosa and assess its suitability for monitoring the epidemiological situation at a CF centre with approximately 300 patients. METHODS: Over a nine-year period, over 300 P. aeruginosa isolates from 131 infected patients were tested by multi-locus sequence typing (MLST) and/or random amplified polymorphic DNA (RAPD) assay. FINDINGS: MLST analysis led to the identification of 97 different sequence types which were distributed among 17 RAPD-generated (pseudo)clusters. This indicates that the easy-to-perform RAPD assay is only suitable for intra-individual, not interindividual, strain analyses. No epidemic strains were observed. Longitudinal analysis revealed that 110 of the 131 patients were infected with the same strain over the observation period, whereas 21 patients had a strain replacement or a new infection. Chronic infection was found in 99 of the 131 patients, and the remaining 32 patients met the criteria for intermittent infection (as defined by the Leeds criteria). Eighteen of the 32 patients (56%) with intermittent infection were infected with the same strain for up to nine years. CONCLUSION: The strain type only changed in 16% of 131 patients with chronic or intermittent infection. As many as 56% of patients considered to have intermittent infection were actually chronically infected with the same strain for many years.

[Bacteria of the Burkholderia cepacia complex: epidemiology and diagnosis of infection in patients with cystic fibrosis]. / Bakterie komplexu Burkholderia cepacia - epidemiologie a diagnostika infekcí u pacientu s cystickou fibrózou.

UNLABELLED: Bacteria of the Burkholderia cepacia complex are the cause of severe lung infections primarily in patients with cystic fibrosis (CF). The risk of epidemic spread of the pathogen in the community of CF patients was the reason for implementing strict isolation measures and identifying the bacterium as early as possible. This review article features the taxonomy of the Burkholderia cepacia complex, possibilities for the laboratory diagnosis of all representatives of this complex, and epidemiological situation in the communities of CF patients in the Czech Republic and in the world. KEYWORDS: Burkholderia cepacia complex - cystic fibrosis - epidemic strain - pathogenesis of the infection.

Recommendations for the classification of diseases as CFTR-related disorders.

Several diseases have been clinically or genetically related to cystic fibrosis (CF), but a consensus definition is lacking. Here, we present a proposal for consensus guidelines on cystic fibrosis transmembrane conductance regulator (CFTR)-related disorders (CFTR-RDs), reached after expert discussion and two dedicated workshops. A CFTR-RD may be defined as "a clinical entity associated with CFTR dysfunction that does not fulfil diagnostic criteria for CF". The utility of sweat testing, mutation analysis, nasal potential difference, and/or intestinal current measurement for the differential diagnosis of CF and CFTR-RD is discussed. Algorithms which use genetic and functional diagnostic tests to distinguish CF and CFTR-RDs are presented. According to present knowledge, congenital bilateral absence of vas deferens (CBAVD), acute recurrent or chronic pancreatitis and disseminated bronchiectasis, all with CFTR dysfunction, are CFTR-RDs.

Burkholderia cenocepacia in cystic fibrosis: epidemiology and molecular mechanisms of virulence.

Burkholderia cepacia complex (Bcc) bacteria have gained notoriety as pathogens in cystic fibrosis (CF) because they are difficult to identify and treat, and also have the ability to spread between CF individuals. Of the 17 formally named species within the complex, Burkholderia multivorans and Burkholderia cenocepacia dominate in CF. Multilocus sequence typing has proven to be a very useful tool for tracing the global epidemiology of Bcc bacteria and has shown that B. cenocepacia strains with high transmissibility, such as the ET-12 strain (ST-28) and the Czech strain (ST-32), have spread epidemically within CF populations in Canada and Europe. The majority of research on the molecular pathogenesis of Bcc bacteria has focused on the B. cenocepacia ET-12 epidemic lineage, with gene mutation, genome sequence analysis and, most recently, global gene expression studies shedding considerable light on the virulence and antimicrobial resistance of this pathogen. These studies demonstrate that the ability of B. cenocepacia to acquire foreign DNA (genomic islands, insertion sequences and other mobile elements), regulate gene expression via quorum sensing, compete for iron during infection, and mediate antimicrobial resistance and inflammation via its membrane and surface polysaccharides are key features that underpin the virulence of different strains. With the wealth of molecular knowledge acquired in the last decade on B. cenocepacia strains, we are now in a much better position to develop strategies for the treatment of pathogenic colonization with Bcc and to answer key questions on pathogenesis concerning, for example, the factors that trigger the rapid clinical decline in CF patients.

Longitudinal observation of enterovirus and adenovirus in stool samples from Norwegian infants with the highest genetic risk of type 1 diabetes.

BACKGROUND: Enterovirus and adenovirus are common in infancy, causing mostly asymptomatic infections. However, even an asymptomatic infection may be associated with increased risk of development of certain chronic non-infectious diseases, as has been suggested for enterovirus and type 1 diabetes. Data on occurrence and course of the infections in infancy are therefore important for designing effective approaches towards study of the association. OBJECTIVES: To estimate the frequency of enterovirus and adenovirus infections in Norwegian infants, to evaluate the duration of the infections, to investigate their association with symptoms, and to establish a robust procedure that will be used to study the association between these viruses and the development of auto-immunity leading to type 1 diabetes. STUDY DESIGN: Parents of infants, recruited for a study on environmental triggers of type 1 diabetes, submitted monthly samples of infant faeces, as well as information on symptoms of infection. The samples were analysed for enterovirus and adenovirus using quantitative real-time PCR, and enterovirus-positive samples were sequenced. RESULTS: Enteroviruses were found in 142/1,255 (11.3%), and adenoviruses in 138/1,255 (11.0%) of stool samples. Approximately half of the infants were exposed to these viruses at least once during the first year of observation (period 3-14 months of age). The presence of adenovirus was associated with fever and with symptoms of cold but not with diarrhoea and vomiting. The enterovirus positivity was not associated with any symptoms. CONCLUSIONS: The prevalence of enterovirus and adenovirus in longitudinally obtained faecal samples from infants is sufficiently high to enable studies of their association with chronic diseases. The present protocol for evaluating exposure to these viruses is well suited for large-scale efforts aimed at assessing possible long-term consequences, particularly in relation to type 1 diabetes.

[Type I diabetes mellitus and associated autoimmune diseases in the first-degree relatives of diabetic children: questionnaire based study]. / Diabetes mellitus 1. typu a sdruzená autoimunitní onemocnení u prvostupnových príbuzných diabetických deti: výsledky dotazníkové studie.

BACKGROUND: Type 1 diabetes mellitus (T1DM) is associated with increased incidence of other autoimmune diseases. The shared genetic background may play a role in the disease pathogenesis. The aim of our study was to assess the prevalence of T1DM and other autoimmune disorders in the first-degree relatives of diabetic children. METHODS AND RESULTS: Data were retrospectively obtained using structured questionnaires from 868 diabetic children younger than 18 years (434 girls and 434 boys, age 12.5 +/- 4.0, mean +/- SD) and their 2704 relatives. The control group included 1466 non-diabetic schoolmates and friends (796 girls, 670 boys, age 11.9 +/- 4.5) and their 4510 first-degree relatives. In the questionnaire we asked about occurrence of thyroid and celiac disease in cases and controls, and about occurrence of T1DM, thyroid and celiac disease in their first-degree relatives. We observed significantly higher prevalence of T1DM in fathers (4.4% vs. 0.8%), mothers (2.0% vs. 0.5%) and siblings (2.5% vs. 0%) of diabetic children compared to controls. Thyroid disease was found significantly more in diabetic children (10.0% vs. 1.9%) and their siblings (3.1% vs. 1.7%). Prevalence of celiac disease was also higher in diabetic children than in controls (3.2% vs. 0.5%), but it does not differ in their first-degree relatives. CONCLUSIONS: We found significantly higher prevalence of thyroid and celiac disease in T1DM children than in controls. Targeted screening and early detection of thyroid and celiac diseases in T1DM patients are likely to be necessary. We observed an increased prevalence of T1DM and thyroid disease in first-degree relatives of diabetic children, however screening of autoimmune diseases associated with T1DM in the first-degree relatives remain controversial.

HLA-DQ polymorphisms modify the risk of thyroid autoimmunity in children with type 1 diabetes mellitus.

OBJECTIVE: Type 1 diabetes mellitus (DM1) is frequently accompanied by thyroid autoimmunity (TAI). The aims of the present study were to estimate the prevalence of TAI and to determine the contribution of HLA-DQA1 and -DQB1 polymorphisms to TAI susceptibility among children with DM1. PATIENTS AND METLHODS: Screening for TAI was performed in 285 children with DM1 by measuring autoantibodies against thyroid peroxidase (anti-TPO) and thyroglobulin (anti-Tg). HLA-DQA1 and -DQB1 were genotyped using PCR-SSP. RESULTS: Repeated positivity of anti-TPO and/or anti-Tg was found in 45/285 children with DM1 (15.8%). The prevalence was significantly higher in girls than in boys (26.7% vs 6.7%; p<10(-5)). The HLA-DQB1*0302 allele conferred susceptibility to TAI in children with DM1 (OR 2.7, 95% CI 1.1-6.4), while the DQB1*05 alleles acted protectively (OR 0.2, CI 95% 0.08-0.7). CONCLUSIONS: HLA-DQ polymorphisms significantly modify the risk of TAI in children with DM1.

The CTLA4 +49 A/G dimorphism is not associated with type 1 diabetes in Czech children.

We investigated the association of the CTLA4 +49 A/G dimorphism with type 1 diabetes in Czech children. Genotyping of 305 diabetic children and 289 controls by a novel PCR-ARMS assay revealed no significant differences in the genotypic or allelic frequencies. This may be another piece of evidence against the +49 A/G transition as the aetiological polymorphism within the CTLA4 gene.