Ivacaftor for Chronic Obstructive Pulmonary Disease - Results from a Phase 2, Randomized Controlled Trial.

RATIONALE: Patients with chronic obstructive pulmonary disease (COPD) exhibit acquired cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction. CFTR modulators may improve outcomes in patients with COPD, although recent data regarding magnitude of benefit have been inconclusive and effects on mucociliary clearance are unknown. We conducted a phase 2, randomized, double blind placebo control trial to determine safety and tolerability, and explore the potential mechanism of ivacaftor for the treatment of COPD. METHODS: We randomized 40 patients with moderate to severe COPD and symptoms of chronic bronchitis to ivacaftor (N=30) or placebo (N=10) 150mg BID for 12 weeks. Primary endpoints included evaluation of safety of ivacaftor and pharmacokinetics (PK). Secondary endpoints included measures of CFTR activity and clinical outcomes. RESULTS: Ivacaftor was safe and tolerable with similar rates of adverse events rates between groups. Most common adverse event was diarrhea in the ivacaftor group and acute COPD exacerbation in the placebo group. PK analysis found the mean area under the curve over 12 hours (AUC12) to be 72% of the previously reported AUC12 in cystic fibrosis (CF). Treatment with ivacaftor did not improve sweat chloride, whole lung mucociliary clearance, lung function or respiratory symptoms. CONCLUSION: Ivacaftor was safe and well tolerated, but did not improve measures of CFTR activity or mucus clearance. As serum concentrations achieved were lower than observed in CF at the same dose, and modulation of wild type CFTR differs from G551D, further dose determination studies are needed to better understand treatment efficacy of CFTR potentiators in COPD. Clinical trial registration available at www. CLINICALTRIALS: gov, ID: NCT03085485.

Evaluation of elexacaftor-tezacaftor-ivacaftor treatment in individuals with cystic fibrosis and CFTRN1303K in the USA: a prospective, multicentre, open-label, single-arm trial.

BACKGROUND: CFTR modulators are approved for approximately 90% of people with cystic fibrosis in the USA and provide substantial clinical benefit. N1303K (Asn1303Lys), one of the most common class 2 CFTR defects, has not been approved for these therapies by any regulatory agency. Preclinical investigation by our laboratories showed N1303K CFTR activation with elexacaftor-tezacaftor-ivacaftor (ETI). In this trial, we evaluate whether ETI improves CFTR function, measured by sweat chloride and other clinical outcomes, in people with cystic fibrosis and CFTRN1303K. METHODS: In this prospective, open-label, single-arm trial, participants aged 12 years or older with cystic fibrosis encoding at least one N1303K variant and at least one CFTRN1303K allele who were ineligible for modulator therapy by US Food and Drug Administration labelling were given ETI for 28 days followed by a 28-day washout period at two cystic fibrosis centres in the USA. Participants received two orally administered pills of 100 mg elexacaftor, 50 mg tezacaftor, and 75 mg ivacaftor once daily in the morning, and 150 mg ivacaftor once daily in the evening. The primary endpoint was mean change in sweat chloride from baseline up to day 28 compared with mixed-effects models. Secondary endpoints were changes in percentage of predicted FEV1 (ppFEV1), Cystic Fibrosis Questionnaire-Revised (CFQ-R) respiratory domain, BMI, and weight after ETI therapy. Safety was assessed in all participants who received at least one dose of the study drug and primary and secondary analyses were performed in all participants who took the study drug per protocol. The trial was registered at ClinicalTrials.gov (NCT03506061) and remains open for reporting purposes. FINDINGS: Between June 7, 2022, and Oct 20, 2023, 20 participants (ten male and ten female) were enrolled and received ETI treatment. One participant was lost to follow-up but was included in intention-to-treat analyses. At 28 days, the mean sweat chloride reduction was -1·1 mmol/L (95% CI -5·3 to 3·1; p=0·61) with only one participant showing a sweat chloride decrease greater than 15 mmol/L. There was a mean increase in ppFEV1 from baseline at day 28 of 9·5 percentage points (6·7-12·3; p<0·0001) with 15 (75%) participants showing at least a 5% increase in ppFEV1. Improvements were also identified in mean CFQ-R respiratory domain score (20·8 increase [95% CI 11·9-29·8]; p<0·0001), BMI (0·4 kg/m2 increase [0·2-0·7]; p=0·0017), and weight (1·0 kg increase [0·4-1·7]; p=0·0020) after 28 days of ETI treatment. 14 (70%) of 20 participants had adverse events (12 [60%] mild, one [5%] moderate), with one (5%) serious adverse event of hospitalisation attributed to pneumonia. No deaths were recorded in the study. INTERPRETATION: Individuals with CFTRN1303K showed no change in sweat chloride after 28 days of treatment with ETI. However, there were improvements in secondary clinical endpoints, which suggest clinical efficacy. Our approach provides support for the use of in vitro model systems to inform clinical trials for rare CFTR variants. FUNDING: The Cystic Fibrosis Foundation and the US National Institutes of Health.

Longitudinal improvements in clinical and functional outcomes following initiation of elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis.

Background: Use of elexacaftor/tezacaftor/ivacaftor (ETI) for treatment of cystic fibrosis (CF) has resulted in unprecedented clinical improvements necessitating development of outcome measures for monitoring disease course. Intranasal micro-optical coherence tomography (µOCT) has previously helped detect and characterize mucociliary abnormalities in patients with CF. This study was done to determine if µOCT can define the effects of ETI on nasal mucociliary clearance and monitor changes conferred to understand mechanistic effects of CFTR modulators beyond CFTR activation. Methods: 26 subjects, with at least 1 F508del mutation were recruited and followed at baseline (visit 1), +1 month (visit 2) and +6 months (visit 4) following initiation of ETI therapy. Clinical outcomes were computed at visits 1, 2 and 4. Intranasal µOCT imaging and functional metrics analysis including mucociliary transport rate (MCT) estimation were done at visits 1 and 2. Results: Percent predicted forced expiratory volume in 1 s (ppFEV1) showed a significant increase of +10.9 % at visit 2, which sustained at visit 4 (+10.6 %). Sweat chloride levels significantly decreased by -36.6 mmol/L and -41.3 mmol/L at visits 2 and 4, respectively. µOCT analysis revealed significant improvement in MCT rate (2.8 ± 1.5, visit 1 vs 4.0 ± 1.5 mm/min, visit 2; P = 0.048). Conclusions: Treatment with ETI resulted in significant and sustained clinical improvements over 6 months. Functional improvements in MCT rate were evident within a month after initiation of ETI therapy indicating that µOCT imaging is sensitive to the treatment effect of HEMT and suggests improved mucociliary transport as a probable mechanism of action underlying the clinical benefits.

Lessons from other fields of medicine, Part 2: Cystic fibrosis.

Cystic fibrosis (CF), first described in 1938, is a common, life-limiting monogenetic disease. The discovery of the cystic fibrosis transmembrane conductance regulator (CFTR) gene in 1989 was crucial in advancing our understanding of disease pathogenesis and paving the road for treatment aimed at the fundamental molecular defect. With the delineation of over 2000 variations in the CFTR gene, a sound understanding of the individual variations in cell biology, and electrophysiological abnormalities conferred by the most common defects propelled the advent of targeted disease-modifying therapeutics beginning in 2012. Since then, CF care has transformed beyond just symptomatic treatment to include a variety of small-molecule therapies that address the basic electrophysiologic defect and cause profound improvements in physiology, clinical manifestations, and long-term outcomes, designed to differentially address six genetic/molecular subtypes. This chapter illustrates the progress made toward how fundamental science and translational initiatives enabled personalized, mutation specific treatment. We highlight the importance of preclinical assays and mechanistically-driven development strategies that were coupled with sensitive biomarkers and a clinical trial cooperative to provide a platform for successful drug development. This convergence of academic and private partnerships, and formation of multidisciplinary care teams directed by evidence-based initiatives provide a seminal example of addressing the needs of individuals with a rare, but fatal genetic disease.

Mucociliary transport deficiency and disease progression in Syrian hamsters with SARS-CoV-2 infection.

Substantial clinical evidence supports the notion that ciliary function in the airways is important in COVID-19 pathogenesis. Although ciliary damage has been observed in both in vitro and in vivo models, the extent or nature of impairment of mucociliary transport (MCT) in in vivo models remains unknown. We hypothesize that SARS-CoV-2 infection results in MCT deficiency in the airways of golden Syrian hamsters that precedes pathological injury in lung parenchyma. Micro-optical coherence tomography was used to quantitate functional changes in the MCT apparatus. Both genomic and subgenomic viral RNA pathological and physiological changes were monitored in parallel. We show that SARS-CoV-2 infection caused a 67% decrease in MCT rate as early as 2 days postinfection (dpi) in hamsters, principally due to 79% diminished airway coverage of motile cilia. Correlating quantitation of physiological, virological, and pathological changes reveals steadily descending infection from the upper airways to lower airways to lung parenchyma within 7 dpi. Our results indicate that functional deficits of the MCT apparatus are a key aspect of COVID-19 pathogenesis, may extend viral retention, and could pose a risk factor for secondary infection. Clinically, monitoring abnormal ciliated cell function may indicate disease progression. Therapies directed toward the MCT apparatus deserve further investigation.

COVID-19 Causes Ciliary Dysfunction as Demonstrated by Human Intranasal Micro-Optical Coherence Tomography Imaging.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2), causative agent of coronavirus disease 2019 (COVID-19), binds via ACE2 receptors, highly expressed in ciliated cells of the nasal epithelium. Micro-optical coherence tomography (µOCT) is a minimally invasive intranasal imaging technique that can determine cellular and functional dynamics of respiratory epithelia at 1-µm resolution, enabling real time visualization and quantification of epithelial anatomy, ciliary motion, and mucus transport. We hypothesized that respiratory epithelial cell dysfunction in COVID-19 will manifest as reduced ciliated cell function and mucociliary abnormalities, features readily visualized by µOCT. Symptomatic outpatients with SARS-CoV-2 aged ≥ 18 years were recruited within 14 days of symptom onset. Data was interpreted for subjects with COVID-19 (n=13) in comparison to healthy controls (n=8). Significant reduction in functional cilia, diminished ciliary beat frequency, and abnormal ciliary activity were evident. Other abnormalities included denuded epithelium, presence of mucus rafts, and increased inflammatory cells. Our results indicate that subjects with mild but symptomatic COVID-19 exhibit functional abnormalities of the respiratory mucosa underscoring the importance of mucociliary health in viral illness and disease transmission. Ciliary imaging enables investigation of early pathogenic mechanisms of COVID-19 and may be useful for evaluating disease progression and therapeutic response.

Mucus Clearance Strategies in Mechanically Ventilated Patients.

The use of airway clearance strategies as supplementary treatment in respiratory disease has been best investigated in patients with cystic fibrosis (CF) and non-cystic fibrosis bronchiectasis (NCFBE), conditions which are traditionally characterized by excessive mucus stasis and mucociliary dysfunction. A variety of airway clearance therapies both pharmacological and non-pharmacological have been shown to ameliorate disease progression in this population and have hence been assimilated into routine respiratory care. This self-propagating cycle of mucus retention and airway damage leading to chronic inflammation and infections can also be applied to patients with respiratory failure requiring mechanical ventilation. Furthermore, excessive trachea-bronchial secretions have been associated with extubation failure presenting an opportunity for intervention. Evidence for the use of adjunctive mucoactive agents and other therapies to facilitate secretion clearance in these patients are not well defined, and this subgroup still remains largely underrepresented in clinical trials. In this review, we discuss the role of mucus clearance techniques with a proven benefit in patients with CF and NCFBE, and their potential role in patients requiring mechanical ventilation while highlighting the need for standardization and adoption of mucus clearance strategies in these patient populations.

Letter to the Editor: "Use of inhaled epoprostenol with high flow nasal oxygen in non-intubated patients with severe COVID-19".

PURPOSE: Acute lung injury associated with COVID-19 contributes significantly to its morbidity and mortality. Though invasive mechanical ventilation is sometimes necessary, the use of high flow nasal oxygen may avoid the need for mechanical ventilation in some patients. For patients approaching the limits of high flow nasal oxygen support, addition of inhaled pulmonary vasodilators is becoming more common but little is known about its effects. This is the first descriptive study of a cohort of patients receiving inhaled epoprostenol with high flow nasal oxygen for COVID-19. MATERIALS AND METHODS: We collected clinical data from the first fifty patients to receive inhaled epoprostenol while on high flow nasal oxygen at our institution. We compared the characteristics of patients who did and did not respond to epoprostenol addition. RESULTS: The 18 patients that did not stabilize or improve following initiation of inhaled epoprostenol had similar rates of invasive mechanical ventilation as those who improved or stabilized (50% vs 56%). Rates of mortality were not significantly different between the two groups (17% and 31%). CONCLUSIONS: In patients with COVID-19 induced hypoxemic respiratory failure, the use of inhaled epoprostenol with high flow nasal oxygen is feasible, but physiologic signs of response were not related to clinical outcomes.

Mucociliary Transport Deficiency and Disease Progression in Syrian Hamsters with SARS-CoV-2 Infection.

Substantial clinical evidence supports the notion that ciliary function in the airways plays an important role in COVID-19 pathogenesis. Although ciliary damage has been observed in both in vitro and in vivo models, consequent impaired mucociliary transport (MCT) remains unknown for the intact MCT apparatus from an in vivo model of disease. Using golden Syrian hamsters, a common animal model that recapitulates human COVID-19, we quantitatively followed the time course of physiological, virological, and pathological changes upon SARS-CoV-2 infection, as well as the deficiency of the MCT apparatus using micro-optical coherence tomography, a novel method to visualize and simultaneously quantitate multiple aspects of the functional microanatomy of intact airways. Corresponding to progressive weight loss up to 7 days post-infection (dpi), viral detection and histopathological analysis in both the trachea and lung revealed steadily descending infection from the upper airways, as the main target of viral invasion, to lower airways and parenchymal lung, which are likely injured through indirect mechanisms. SARS-CoV-2 infection caused a 67% decrease in MCT rate as early as 2 dpi, largely due to diminished motile ciliation coverage, but not airway surface liquid depth, periciliary liquid depth, or cilia beat frequency of residual motile cilia. Further analysis indicated that the fewer motile cilia combined with abnormal ciliary motion of residual cilia contributed to the delayed MCT. The time course of physiological, virological, and pathological progression suggest that functional deficits of the MCT apparatus predispose to COVID-19 pathogenesis by extending viral retention and may be a risk factor for secondary infection. As a consequence, therapies directed towards the MCT apparatus deserve further investigation as a treatment modality.

Inhaled high molecular weight hyaluronan ameliorates respiratory failure in acute COPD exacerbation: a pilot study.

BACKGROUND: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) carry significant morbidity and mortality. AECOPD treatment remains limited. High molecular weight hyaluronan (HMW-HA) is a glycosaminoglycan sugar, which is a physiological constituent of the lung extracellular matrix and has notable anti-inflammatory and hydrating properties. RESEARCH QUESTION: We hypothesized that inhaled HMW-HA will improve outcomes in AECOPD. METHODS: We conducted a single center, randomized, placebo-controlled, double-blind study to investigate the effect of inhaled HMW-HA in patients with severe AECOPD necessitating non-invasive positive-pressure ventilation (NIPPV). Primary endpoint was time until liberation from NIPPV. RESULTS: Out of 44 screened patients, 41 were included in the study (21 for placebo and 20 for HMW-HA). Patients treated with HMW-HA had significantly shorter duration of NIPPV. HMW-HA treated patients also had lower measured peak airway pressures on the ventilator and lower systemic inflammation markers after liberation from NIPPV. In vitro testing showed that HMW-HA significantly improved mucociliary transport in air-liquid interface cultures of primary bronchial cells from COPD patients and healthy primary cells exposed to cigarette smoke extract. INTERPRETATION: Inhaled HMW-HA shortens the duration of respiratory failure and need for non-invasive ventilation in patients with AECOPD. Beneficial effects of HMW-HA on mucociliary clearance and inflammation may account for some of the effects (NCT02674880, www.clinicaltrials.gov ).

Subcutaneous formulation of belimumab in treatment of systemic lupus erythematosus: a critical review with focus on safety and satisfaction.

Belimumab is a novel add-on therapy that has been approved for patients with active and antibody-mediated systemic lupus erythematosus. It is a monoclonal antibody that decreases the activation of B-cells and consequently decreases antibodies' production. Recently, the US Food and Drug Administration approved subcutaneous belimumab for patients who have received training on using it. Subcutaneous belimumab can be administered using either a prefilled syringe or an auto-injector device. Weekly subcutaneous belimumab seems to be as effective as monthly intravenous belimumab with a similar safety margin. In this article, we reviewed the literature on subcutaneous belimumab focusing on safety and patients' experiences and satisfaction. Overall, subcutaneous belimumab appears to be preferred over intravenous belimumab for a number of reasons. However, more studies are still required to prove these findings.

Giant axonal neuropathy.

Giant axonal neuropathy is an autosomal recessive disorder of childhood with distinct morphological features. An 8-year-old boy presented with progressive walking difficulty and recurrent falls. Evaluation showed frizzy hair, characteristic facies, sensory motor neuropathy, and ataxia. Magnetic resonance imaging (MRI) showed bilateral symmetric white matter signal changes in the cerebellum and periventricular regions along with involvement of the posterior limb of the internal capsule. Sural nerve biopsy demonstrated giant axons with neurofilament accumulation. The clinicopathologic manifestations of giant axonal neuropathy are discussed along with the clinical and histologic differential diagnoses.

Brain diabetic neurodegeneration segregates with low intrinsic aerobic capacity.

OBJECTIVES: Diabetes leads to cognitive impairment and is associated with age-related neurodegenerative diseases including Alzheimer's disease (AD). Thus, understanding diabetes-induced alterations in brain function is important for developing early interventions for neurodegeneration. Low-capacity runner (LCR) rats are obese and manifest metabolic risk factors resembling human "impaired glucose tolerance" or metabolic syndrome. We examined hippocampal function in aged LCR rats compared to their high-capacity runner (HCR) rat counterparts. METHODS: Hippocampal function was examined using proton magnetic resonance spectroscopy and imaging, unbiased stereology analysis, and a Y maze. Changes in the mitochondrial respiratory chain function and levels of hyperphosphorylated tau and mitochondrial transcriptional regulators were examined. RESULTS: The levels of glutamate, myo-inositol, taurine, and choline-containing compounds were significantly increased in the aged LCR rats. We observed a significant loss of hippocampal neurons and impaired cognitive function in aged LCR rats. Respiratory chain function and activity were significantly decreased in the aged LCR rats. Hyperphosphorylated tau was accumulated within mitochondria and peroxisome proliferator-activated receptor-gamma coactivator 1α, the NAD(+)-dependent protein deacetylase sirtuin 1, and mitochondrial transcription factor A were downregulated in the aged LCR rat hippocampus. INTERPRETATION: These data provide evidence of a neurodegenerative process in the hippocampus of aged LCR rats, consistent with those seen in aged-related dementing illnesses such as AD in humans. The metabolic and mitochondrial abnormalities observed in LCR rat hippocampus are similar to well-described mechanisms that lead to diabetic neuropathy and may provide an important link between cognitive and metabolic dysfunction.