CFTR Modulators Research Articles

CFTR function is impaired in a subset of patients with pancreatitis carrying rare CFTR variants

BackgroundMany affected by pancreatitis harbor rare variants of the cystic fibrosis (CF) gene, CFTR, which encodes an epithelial chloride/bicarbonate channel. We investigated CFTR function and the effect of CFTR modulator drugs in pancreatitis patients carrying CFTR variants. MethodsNext-generation sequencing was performed to identify CFTR variants. Sweat tests and nasal potential difference (NPD) assays were performed to assess CFTR function in vivo. Intestinal current measurement (ICM) was performed on rectal biopsies. Patient-derived intestinal epithelial monolayers were used to evaluate chloride and bicarbonate transport and the effects of a CFTR modulator combination: elexacaftor, tezacaftor and ivacaftor (ETI). ResultsOf 32 pancreatitis patients carrying CFTR variants, three had CF-causing mutations on both alleles and yielded CF-typical sweat test, NPD and ICM results. Fourteen subjects showed a more modest elevation in sweat chloride levels, including three that were provisionally diagnosed with CF. ICM indicated impaired CFTR function in nine out of 17 non-CF subjects tested. This group of nine included five carrying a wild type CFTR allele. In epithelial monolayers, a reduction in CFTR-dependent chloride transport was found in six out of 14 subjects tested, whereas bicarbonate secretion was reduced in only one individual. In epithelial monolayers of four of these six subjects, ETI improved CFTR function. ConclusionsCFTR function is impaired in a subset of pancreatitis patients carrying CFTR variants. Mutations outside the CFTR locus may contribute to the anion transport defect. Bioassays on patient-derived intestinal tissue and organoids can be used to detect such defects and to assess the effect of CFTR modulators.

Longitudinal Evaluation of Physical Fitness in Adults with Cystic Fibrosis in the Era of CFTR-Modulating-Therapies

ABSTRACT Purpose: Maintaining physical fitness plays an important role in the management of people with cystic fibrosis (pwCF). Longitudinal data on the course of physical fitness and the potential impact of the introduction of highly effective CFTR modulator therapy with elexacaftor/tezacaftor/ivacaftor (ETI) in adult pwCF are scarce. Methods: Health-related and skill-related components of physical fitness were assessed using an incremental cycle test (Wpeak), plus forward bend (FB), prone bent knee hip extension (HE), plank leg raise (PLR), standing long jump (SLJ), and standing on one leg (OLS). Relevant disease-specific clinical data (body mass index [BMI] and forced expiratory volume in 1 second [FEV1]) were recorded. Results: Twenty-eight adult pwCF (age 26.0 ± 7.8 years) were followed over 5.6 ± 0.9 years; 21 started ETI therapy during this period. Significant improvements from baseline were noted in BMI (p < 0.001) and health-related fitness components (HE, p = 0.002; PLR, p = < 0.001), whereas Wpeak and FB remained stable over time (all p > 0.05). Skill-related components (SLJ, OLS) showed no change (all p > 0.05). Subgroup analysis revealed significant improvements in BMI, FEV1, and health-related fitness measures of muscular strength and endurance (HE, p = 0.009; PLR, p < 0.001) only in pwCF using ETI. Conclusion: Despite the improvements, the impact of ETI on the individual parameters was small. Other factors than implementation of ETI alone need to be considered on the way to a high level of physical fitness in adult pwCF.

Сhronic rhinosinusitis in adult patients with cystic fibrosis receiving CFTR modulators

Cystic fibrosis-associated chronic rhinosinusitis (CRS) is a separate form of CRS that progresses gradually over the course of patient’s life and worsens with age. The reasons for this are the mechanical congestion of mucus in the paranasal sinuses and the persistence of colonies of pathogenic antibiotic-resistant microorganisms. Therapy with CFTR modulators has resulted in a significant reduction in the severity of CRS. The nature of these changes and the dynamics in the microbial landscape of the upper respiratory tract are not sufficiently explored.Aim of the article is to highlight various aspects of the impact of CFTR modulators on the course of CRS in adult patients with cystic fibrosis (CF) based on literature data and a number of our own clinical observations. The article presents a series of clinical cases of CRS in adult CF patients treated with CFTR modulators for different periods of time.Conclusion. During targeted therapy with CFTR modulators, the symptoms of CRS are reversed due to the restoration of normal rheological properties of nasal secretions, the clinical picture improves, and the severity of CRS decreases. However, this type of treatment has no direct effect on the microbial landscape of the respiratory tract and requires additional interventions in the form of local and systemic antibacterial therapy. Therapy with CFTR modulators alters the course of CF in the nasal cavity, as well as in the pharynx and larynx.

Diagnosis, Management, and Prognosis of Cystic Fibrosis-Related Liver Disease in Children.

Cystic fibrosis (CF) is a multifaceted disorder predominantly investigated for its pulmonary manifestations, yet patients with CF also exhibit a spectrum of extrapulmonary manifestations, notably those involving the hepatobiliary system. The latter constitutes the third leading cause of morbidity and mortality in individuals with CF. Cystic fibrosis-related liver disease (CFLD), with an escalating prevalence, manifests diverse clinical presentations ranging from hepatomegaly to cirrhosis and hepatopulmonary syndrome. Consequently, early detection and appropriate management are imperative for sustaining the health and influencing the quality of life of CF patients afflicted with CFLD. This review aims to consolidate existing knowledge by providing a comprehensive overview of hepatobiliary manifestations associated with CF. It delineates the clinical hepatobiliary manifestations, diagnostic methodologies, incorporating minimally invasive markers, and therapeutic approaches, encompassing the impact of novel CFTR modulators on CFLD. Given the exigency of early diagnosis and the intricate management of CFLD, a multidisciplinary team approach is essential to optimize care and enhance the quality of life for this subset of patients. In conclusion, recognizing CF as more than solely a pulmonary ailment, the authors underscore the imperative for further clinical investigations to establish a more robust evidence base for CFLD management within the continuum of this chronic disease.

Therapeutics in cystic fibrosis: Clinical revolution and new challenges

Over time, cystic fibrosis has become a model of synergy between research in pathophysiology and cell biology, and clinical advances. Therapies targeting the CFTR protein, in particular CFTR modulators, have transformed the prognosis of patients, bringing the hope of a normal life with the possibility of starting a family and growing old, challenging established statistics. However, patients are not yet cured, and side effects remain insufficiently documented. Epidemiological changes create new challenges for the management of cystic fibrosis. Approximately 10 % of patients still lack a therapeutic option. The community of researchers, pharmaceutical industries, patient associations, and health authorities remains committed to monitor the long-term effects of these still poorly characterised treatments, and to explore new pharmacological approaches, such as gene therapies.

Dual and triple modulator therapy for chronic rhinosinusitis in cystic fibrosis patients.

The introduction of CFTR modulators has changed the landscape in the treatment of cystic fibrosis (CF) and early case series have shown improvements in sinonasal outcomes in this patient population. A real-word data study was performed to evaluate the impact of dual therapy with tezacaftor/ivacaftor (TEZ/IVA) and triple therapy with elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) on CF-related chronic rhinosinusitis (CRS), by comparing subjective and objective outcome measures at baseline, 12 months after treatment with TEZ/IVA and six months after treatment with ELX/TEZ/IVA. In total, 43 CF patients, with a mean age of 32 years, were included. After triple therapy, significant improvements in overall visual analogue scale, SNOT-22, Lund Kennedy, nasal polyps, and Lund-Mackay scores were observed, whereas no beneficial effect could be seen in patients treated with dual therapy. Bacterial upper airway colonization did not differ pre- and postmodulator therapy in the present study. The number of responders to dual and triple therapy is 23.8% and 63.2% of the patients, respectively. Triple therapy with ELX/TEZ/IVA is superior to dual therapy with TEZ/IVA in the treatment of CF-CRS, as significantly reduced sinonasal complaints, nasal endoscopy and CT scores were observed after triple therapy, whereas this was not the case for dual therapy.

Clinical outcomes of functional endoscopic sinus surgery in cystic fibrosis patients - a single centre experience.

Endoscopic sinus surgery (ESS) is an established surgical option for cystic fibrosis (CF) patients with chronic rhinosinusitis that is refractory to conventional medical management. Objective and subjective evidence of benefit of ESS in this cohort of patients is currently conflicting in the literature. A single center retrospective study was undertaken of all CF patients (transplanted and non-transplanted) over the age of 16 who underwent an ESS over a six-year period from 2015 to 2021. Patients on triple-therapy CFTR modulators were excluded. Data was collected on demographics, clinical management, and outcome measures. The objective outcome measures were lung function (%predicted FEV1), pulmonary exacerbations (total number of days of IV antibiotics- both ambulatory and in hospital). The subjective outcome measure was SNOT-22 scores pre and 6 months post-operatively. A minimally clinical important difference (MCID) in SNOT-22 scores of 9 points was used. 55 patients were included in our study, with a median age of 31 and 53% females. Median Lund-Mackay scores for the cohort was 13 (3-24). There was a significant improvement in lung function at 1-year post-surgery, and a significant MCID reduction in SNOT-22 scores at 6 months post-surgery across the cohort. Sub-group analysis revealed a sustained MCID reduction in SNOT-22 scores in both lung-transplanted and native lung groups, and in patients with primary ESS or previous ESS. However, there was no post-operative pulmonary function improvement in lung transplanted patients and patients with previous ESS. There was no impact on the rate of pulmonary exacerbations across the cohort. 2 patients in the cohort died secondary to pulmonary disease. There was a demonstrated clinical and symptomatic benefit of ESS in CF patients in this study. Stricter guidelines for indications for ESS need to be established with regards to CF patients who will undergo ESS in the future.

Efficacy and safety of triple therapy (elexacaftor/tezacaftor/ ivacaftor) in children with cystic fibrosis: 12-month follow-up

The most effective drug for targeted therapy of cystic fibrosis (CF) today is the CFTR modulator elexacaftor/tezacaftor/ivacaftor. It is a combination of two CFTR correctors and a CFTR potentiator that correct the main genetic defect in patients with CF who carry at least one genetic variant specified in the instructions for use of the drug. In the Russian Federation, children with CF at the age of 6 years and older are provided with a targeted drug at the expense of the Circle of Kindness Charitable Foundation.The aim of the study was to investigate the efficacy and safety of therapy with the CFTR modulator elexacaftor/thezacaftor/ivacaftor in children with cystic fibrosis during 12 months of follow-up.Methods. The data of 48 patients aged 6 to 18 years who received targeted therapy with elexacaftor/tezacaftor/ivacaftor in 2021 and were included in the “Targeted therapy” section of the Register of Patients with Cystic Fibrosis in the Russian Federation, were analyzed. To study the effectiveness and safety of the therapy, the patients’ nutritional status, sweat test, respiratory function, blood chemistry, blood pressure, and lens condition were monitored during the therapy.Results. During therapy, an increase in body weight was noted from 44.1 (± 8.8) to 50.1 (± 7.8) kg (M ± SD) (p &lt; 0.001); height, from 158.2 (± 9.1) to 161.9 (± 8.7) cm (p &lt; 0.001); and BMI, from 17.5 (± 2.3) to 19 (± 1.9) kg / m2 (p &lt; 0.001). The conductivity of sweat decreased from 114.8 (± 17.4) at the start of triple therapy to 73.9 (± 20.6) mmol/l NaCl (p &lt; 0.001) after 12 months of treatment. In 28.5%, the sweat test results returned to normal (the sweat conductivity was equivalent to &lt; 50 mmol / l NaCl). Statistically significant changes in the indices of respiratory function were obtained: the forced vital capacity increased from 72.8%pred. (± 21.7) to 86.6%pred. (± 24.4) (p &lt; 0.001), FEV1 – from 67.2%pred. (± 21.7) to 84.9%pred. (± 28.9) (p &lt; 0.001).Conclusion. Analysis of the tolerability showed a consistent safety profile of the triple therapy.

The Changing Landscape of Treatment for Cystic Fibrosis Related Diabetes

ObjectivePatients with Cystic Fibrosis related diabetes [CFRD] are treated with insulin and high calorie diets to maintain body mass. The combined CFTR modulator elexacaftor/tezacaftor/ivacaftor [ETI] decreases pulmonary exacerbations and improves nutritional status. We reviewed the effects of ETI on BMI, HbA1c and diabetes regimen in patients with CFRD over a period of three years. MethodsData of previously CFTR-modulator-naïve patients with CFRD and pancreatic insufficiency on ETI therapy were retrieved from an electronic health record database. Patients were followed for a mean duration of 2.7 ± 0.8 years after ETI initiation. Data pertaining to weight, BMI, HbA1c and diabetes regimen were collected at 6 months, 12 months, 2 years and at 3 years post-ETI initiation. Patients were then dichotomized based on their baseline BMI into a low BMI group and an “at target” BMI group. The effects of ETI on changes in weight, BMI, A1c and diabetes regimen were compared in both groups over a period of three years. ResultsTwenty-seven patients with CFRD (15 men/12 women), age 30.6 ± 11.5 (SD) years, BMI 22.4 ± 4.0 kg/m2, were included. Fifteen patients had low BMI (<22 kg/m2 for women, <23 kg/m2 for men) and 12 patients had at target BMI (≥22 kg/m2for women, ≥BMI 23 kg/m2 for men). Patients with low BMI had an increase in their BMI from 19.5 ± 1.7 to 21.4 ± 2.2 kg/m2 at one year (p = 0.002), and 21.8 ± 1.8 kg/m2 at three years (p = 0.004) after ETI initiation. Four patients (out of 15) in the low BMI group had achieved normal BMI by the end of study follow up. There was no change in weight in the at target BMI group. HbA1c and basal insulin requirements did not change in either group. Five patients started non-insulin therapies. ConclusionBMI increased after ETI therapy in CFRD patients with low BMI, but not in those with at target BMI. The use of non-insulin therapies is increasing in CFRD and should be evaluated in future studies.

Comprehensive Assessment of CFTR Modulators' Therapeutic Efficiency for N1303K Variant.

p.Asn1303Lys (N1303K) is a common missense variant of the CFTR gene, causing cystic fibrosis (CF). In this study, we initially evaluated the influence of CFTR modulators on the restoration of N1303K-CFTR function using intestinal organoids derived from four CF patients expressing the N1303K variant. The forskolin-induced swelling assay in organoids offered valuable insights about the beneficial effects of VX-770 + VX-661 + VX-445 (Elexacaftor + Tezacaftor + Ivacaftor, ETI) on N1303K-CFTR function restoration and about discouraging the prescription of VX-770 + VX-809 (Ivacaftor + Lumacaftor) or VX-770 + VX-661 (Ivacaftor + Tezacaftor) therapy for N1303K/class I patients. Then, a comprehensive assessment was conducted on an example of one patient with the N1303K/class I genotype to examine the ETI effect on the restoration of N1303K-CFTR function using in vitro the patient's intestinal organoids, ex vivo the intestinal current measurements (ICM) method and assessment of the clinical status before and after targeted therapy. All obtained results are consistent with each other and have proven the effectiveness of ETI for the N1303K variant. ETI produced a significant positive effect on forskolin-induced swelling in N1303K/class I organoids indicating functional improvement of the CFTR protein; ICM demonstrated that ETI therapy restored CFTR function in the intestinal epithelium after three months of treatment, and the patient improved his clinical status and lung function, increased his body mass index (BMI) and reduced the lung pathogenic flora diversity, surprisingly without improving the sweat test results.

Longitudinal changes in habitual physical activity in adult people with cystic fibrosis in the presence or absence of treatment with elexacaftor/tezacaftor/ivacaftor.

Habitual physical activity (PA) and exercise training are accepted as important aspects of care for people with cystic fibrosis (pwCF) to improve health-related measures of physical fitness, which in turn have a positive impact on quality of life and prognosis. In the last decade, effective CFTR modulator therapies have become a promising treatment for pwCF by targeting the underlying cause of CF. This highly effective therapy improves clinical outcomes and quality of life in people with specific CFTR mutations. Little is known about the longitudinal pattern of PA or the impact of the highly effective modulator therapy with Elexacaftor/Tezacaftor/Ivacaftor (ETI) on PA in adult pwCF. This study assessed the course of device-based PA measurement in adult pwCF and evaluated the effects of ETI on habitual physical activity in those who were eligible for ETI. Data from adult pwCF (aged ≥18 years) were analysed at baseline and follow-up, using identical assessments at both time points. Outcome parameters were PA in steps/day and the intensity of PA. The group that received ETI was treated for an average of 33 weeks and not for the entire duration of the period. The data were collected between 2021 and 2022, following the removal of absolute pandemic restrictions/lockdowns. Follow-up duration was 5.6 years in pwCF with ETI (ETI group, n = 21) and 6.5 years in pwCF without ETI (non-ETI group, n = 6). From baseline to follow-up, pwCF treated with ETI had a significant increase in steps/day (+25%, p = 0.019) and a non-significant increase in moderate-to-vigorous intensity time (+5.6%, p = 0.352). Conversely, individuals in the non-ETI group showed a non-significant decrease in both steps/day -3.2%, p = 0.893) and moderate-to-vigorous intensity time (-25%, p = 0.207). The ETI group showed a significant decrease in percent predicted forced expiratory volume in 1 s (ppFEV1) and FEV1 z-score before the start of ETI treatment, both of which improved significantly after therapy initiation. Body weight and body mass index also improved significantly with ETI use. These data suggest that ETI treatment has a positive effect on habitual physical activity behavior in the adult pwCF studied.

One year effect of tezacaftor and ivacaftor on functional exercise capacity and muscle strength in people with cystic fibrosis

BackgroundThe 1-min sit-to-stand test (1STST) is a practical tool to evaluate physical capacity. The aim of this study was to assess the impact of tezacaftor and ivacaftor on functional exercise capacity, muscle strength and symptoms in people with cystic fibrosis (PwCF). MethodsThe assessments were performed during the first year of tezacaftor and ivacaftor using the 1STST, 6-min walk test (6MWT), MicroFET2 dynamometer®, CF Questionnaire-Revised (CFQ-R), Leicester Cough Questionnaire (LCQ). Forced expiratory volume in 1 s (FEV1), body mass index (BMI), pancreatic sufficiency status, genotype and microbiologic data were also collected. ResultsFifty-four PwCF participated to the study and took at least one dose of tezacaftor-ivacaftor. Mean age was 26y±10 (±SD), median BMI 20.9 kg/m2 (interquartile range) (19.4; 23.5) and mean FEV1 82 percent of predicted values (%PV) ± 21. Significant correlations were found at baseline between the 1STST and the 6MWT (r = 0.617, p < 0.0001), the quadriceps strength (r = 0.6556, p < 0.0001) and the FEV1 (r = 0.29, p = 0.03). After one year of treatment, the 1STST increased significantly in terms of number of repetitions (n) (median 50 versus 58.5, p < 0.0001), %PV (101.1 versus 115.2%PV, p = 0.0003) and n times weight in kg (2885 versus 3389nxkg, p < 0.0001). The 6MWT distance and quadriceps strength were not modified after treatment but during the 6MWT, oxygen desaturation decreased significantly. FEV1, BMI, CFQ-R, LCQ improved as previously demonstrated. ConclusionAfter one year of tezacaftor and ivacaftor, the 1STST improves, suggesting that the 1STST seems more responsive than the 6MWT and the MicroFET2 dynamometer® to assess the effects of CFTR modulators.

Inhaled antimicrobial prescribing for Pseudomonas aeruginosa infections in Europe

BackgroundPrescribers have an increasing range of inhaled antimicrobial formulations to choose from when prescribing both eradication and chronic suppression regimens in cystic fibrosis (CF). This study aimed to investigate the decision-making process behind prescribing of inhaled antimicrobials for Pseudomonas aeruginosa infections. MethodsA questionnaire was developed using Microsoft Forms and then forwarded to 57 Principal Investigators (PIs), at each of the CF centres within the European Cystic Fibrosis Society-Clinical Trials Network (ECFS-CTN). Data collection occurred between November 2021 and February 2022. ResultsThe response rate was 90 % (n = 51/57 PIs), with at least 50 % of CF centers in each of the 17 countries represented in the ECFS-CTN. Physicians used a median of eight factors in their decision-making process with delivery formulations (92.2 %), adherence history (84.3 %), and antibiotic side-effect profile (76.5 %) often selected. Nebulised tobramycin or colistin were frequently selected as the inhaled antimicrobial in first-line eradication (n = 45, 88.2 %) and chronic suppression regimens (n = 42, 82.4 %). Combination regimens were more often chosen in eradication (first-line: n = 35, 68.6 %, second-line: n = 34, 66.7 %) and later chronic suppression regimens (third-line: n = 27, 52.9 %) than monotherapy. For pwCF also prescribed CFTR modulator therapies, most PIs did not alter inhaled antimicrobial regimens (n = 40, 78.4 %), with few pwCF (n = 18, 35.3 %) or PIs (n = 10, 19.6 %) deciding to stop inhaled antimicrobials. ConclusionsThe inhaled antimicrobial prescribing decision-making process is multifactorial. Nebulised tobramycin or colistin are often used in initial eradication and chronic suppression regimens. To date, CFTR modulator therapy has had a limited impact on the prescribing of inhaled antimicrobial regimens.

Organic Synthesis and Current Understanding of the Mechanisms of CFTR Modulator Drugs Ivacaftor, Tezacaftor, and Elexacaftor.

The monogenic rare disease Cystic Fibrosis (CF) is caused by mutations in the gene encoding the CF transmembrane conductance (CFTR) protein, an anion channel expressed at the apical plasma membrane of epithelial cells. The discovery and subsequent development of CFTR modulators-small molecules acting on the basic molecular defect in CF-have revolutionized the standard of care for people with CF (PwCF), thus drastically improving their clinical features, prognosis, and quality of life. Currently, four of these drugs are approved for clinical use: potentiator ivacaftor (VX-770) alone or in combination with correctors lumacaftor, (VX-809), tezacaftor (VX-661), and elexacaftor (VX-445). Noteworthily, the triple combinatorial therapy composed of ivacaftor, tezacaftor, and elexacaftor constitutes the most effective modulator therapy nowadays for the majority of PwCF. In this review, we exploit the organic synthesis of ivacaftor, tezacaftor, and elexacaftor by providing a retrosynthetic drug analysis for these CFTR modulators. Furthermore, we describe the current understanding of the mechanisms of action (MoA's) of these compounds by discussing several studies that report the key findings on the molecular mechanisms underlying their action on the CFTR protein.

Lumacaftor/Ivacaftor Population Pharmacokinetics in Pediatric Patients with Cystic Fibrosis: A First Step Toward Personalized Therapy.

A major breakthrough in cystic fibrosis (CF) therapy was achievedAQ1 with CFTR modulators. The lumacaftor/ivacaftor combination is indicated for the treatment of CF in pediatric patients above 6 years old. Pharmacokinetic (PK) studies of lumacaftor/ivacaftor in these vulnerable pediatric populations are AQ2crucial to optimize treatment protocols. The objectives of this study were to describe the population PK (PPK) of lumacaftor and ivacaftor in children with CF, and to identify factors associated with interindividual variability. The association between drug exposure and clinical response was also investigated. A total of 75 children were included in this PPK study, with 191 concentrations available for each compound and known metabolites (lumacaftor, ivacaftor, ivacaftor-M1, and ivacaftor-M6). PPK analysis was performed using Monolix software. A large interindividual variability was observed. The main sources of interpatient variability identified were patient bodyweight and hepatic function (aspartate aminotransferase). Forced expiratory volume in the first second (FEV1) was statistically associated with the level of exposure to ivacaftor after 48 weeks of treatment. This study is the first analysis of lumacaftor/ivacaftor PPK in children with CF. These data suggest that dose adjustment is required after identifying variability factors to optimize efficacy. The use of therapeutic drug monitoring as a basis for dose adjustment in children with CF may be useful.

Changes in sleep in people with cystic fibrosis and primary ciliary dyskinesia over time and after CFTR modulator therapy

Changes in sleep in people with cystic fibrosis and primary ciliary dyskinesia over time and after CFTR modulator therapy

How to improve the management of pregnancy in a patient with cystic fibrosis during cftr modulators therapy

How to improve the management of pregnancy in a patient with cystic fibrosis during cftr modulators therapy

Fetal drug exposure after maternally administered CFTR modulators Elexacaftor/Tezacaftor/Ivacaftor in a rat model

BackgroundThe potential effects of the very effective cystic fibrosis triple combination drug, Elexacaftor/Tezacaftor/Ivacaftor (ETI) in pregnancy on prenatal development of offspring remain largely unknown. Research questionWe aimed to investigate the fetal tissue distribution pattern of maternally administered ETI by placental transfer in the rat fetuses. Study design and methodsSprague Dawley pregnant rats were administered ETI (6.7 mg/kg/d elexacaftor + 3.5 mg/kg/d tezacaftor + 25 mg/kg/d ivacaftor) traced with [3 H]-ivacaftor in single dose acute experiments (intraperitoneal injection) or treated orally with ETI (the same dose) for 7 days in sub-chronic experiments. Fetal tissue samples were collected at embryonic day (E) 19 and analyzed using liquid scintillation counting for acute experiments or liquid chromatography-mass spectrometry for sub-chronic experiments. ResultsOn day E19, after acute exposure, the entry of ivacaftor into fetal brain (brain/plasma concentration ratios <50%) was significantly lower than to other tissues (>100%). However, after sub-chronic exposure, the entry of all 3 components into the developing brain was comparably extensive as into other tissues (tissue/plasma ratios, 260 – 1000%). Each component of ETI accumulated in different fetal tissues to approximately equal extent. Inter-litter differences on fetal drug distribution were found in cortex for ivacaftor, muscle for tezacaftor and cortex and mid/hindbrain for elexacaftor. Fetal plasma concentrations of ETI (ng/mL) were variable between litters. The entry of ivacaftor and tezacaftor into adult brain appeared to be restricted (<100%). InterpretationFetal rats are exposed to maternally ingested ETI after sub-chronic exposure, potentially impacting fetal development. The brain entry data highlights the need for attention be paid to any long-term potential effects ETI exposure could have on normal brain development.

Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues

This is the third in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation.Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family.CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey.

Cystic fibrosis in the era of CFTR modulators: did the neutrophil slip through the cracks?

Neutrophil abnormalities are present in patients with cystic fibrosis treated with CFTR modulators.