Flow Cytometry as an Alternative to Microscopy for the Differentiation of BAL Fluid Leukocytes.

BACKGROUND: Microscopy is currently the gold standard to differentiate BAL fluid (BALF) leukocytes. However, local expertise for microscopic BALF leukocyte differentiation is often unavailable in clinical practice. RESEARCH QUESTION: Can automated flow cytometry be used instead of microscopy to differentiate BALF leukocytes? STUDY DESIGN AND METHODS: A new automated flow cytometric method for BALF leukocyte differentiation, using four antibodies (anti-CD45, anti-CD66b, anti-HLA-DR, anti-CD52) given to human BALF in one tube, was developed and prospectively validated in 745 unselected subsequent BALF samples from patients with interstitial lung diseases (455 patients), infectious diseases (196 patients), and other diseases (94 patients). Flow cytometry and traditional microscopy were performed by separate investigators in a double-anonymized fashion. Results were compared using Spearman correlation, Deming regression, and Bland-Altman analysis. RESULTS: There was a strong correlation between flow cytometric and microscopic results regarding macrophage/monocyte, lymphocyte, eosinophil, and neutrophil percentages in BALF (P < .001 for all leukocyte subpopulations). Bland-Altman analyses showed that the mean differences between the methods were ≤ 2% for all four cell types. Flow cytometric results differed less than 20% from microscopic results in more than 95% of all samples. Subgroup analyses confirmed that these results were independent from total leukocyte counts in BALF. INTERPRETATION: We report, to our knowledge, the first validated flow cytometric method for BALF leukocyte differentiation, which can be used in clinical settings where local expertise for microscopic analysis is unavailable and which can be combined easily with lymphocyte surface marker analysis.

Allergen immunotherapy for allergic asthma.

Remission is the goal of modern asthma treatment. Allergen immunotherapy (AIT) is an essential component in the armamentarium of personalized asthma therapy. Subcutaneous AIT (SCIT) or sublingual AIT (SLIT) offer the possibility to prevent asthma in patients with allergic rhinitis (reduction of the risk of developing asthma) and the possibility to achieve remission in patients with allergic asthma. Accordingly, AIT should always be considered in patients with asthma and a documented, clinically relevant allergy. However, precise phenotyping of the patient is an essential prerequisite for a success of AIT in asthma.

Response to Various Biologics in Patients with Both Asthma and Chronic Obstructive Pulmonary Disease.

INTRODUCTION: Patients can have features of both chronic obstructive pulmonary disease (COPD) and asthma. However, there is still no consensus how to precisely define this patient population. In addition, there are little data on the effectiveness of biologics in these patients. METHOD: Presence of COPD was defined by a smoking history of ≥10 pack years (PY), a postbronchodilator FEV1/FVC ratio < lower limit of normal (LLN) and FEV1 < 80% predicted, a carbon monoxide diffusion capacity (DLCO) < LLN, and dyspnoea on exertion as a leading symptom. Presence of asthma was defined by high type 2 biomarkers (blood eosinophils ≥300 cells/µL and/or FeNO ≥50 ppb), typical clinical features of asthma (including nocturnal respiratory symptoms), and a documented history of a clinical benefit from inhaled and/or oral glucocorticoid treatment. We analysed data from 20 patients fulfilling the criteria for both COPD and asthma who were newly treated with a biologic due to recurrent exacerbations despite high-dose inhaled triple therapy. RESULTS: Median values before treatment with a biologic were as follows: 40 PY, FEV1 42% predicted, DLCO 45% predicted, 475 eosinophils/µL blood, FeNO 48 ppb. Median duration of biologic treatment (mepolizumab, benralizumab, dupilumab, omalizumab, or tezepelumab) was 12 months. There were significant improvements in exacerbations (most prominent effect), asthma control, and lung function during biologic treatment. CONCLUSIONS: Various types of biologics approved for severe asthma treatment can be effective in patients with both COPD and asthma. We propose an easy-to-use definition of these patients for routine clinical practice.

Comparison of the Asthma Control Questionnaire and patient diaries in uncontrolled asthma.

These post hoc analyses suggest that the Asthma Control Questionnaire and eDiary have different measurement properties, and it is therefore potentially valuable to include both in clinical trials https://bit.ly/3TIYClX.

Dupilumab efficacy in subgroups of type 2 asthma with high-dose inhaled corticosteroids at baseline.

BACKGROUND AND OBJECTIVE: Dupilumab blocks the shared receptor component for interleukin (IL)-4/IL-13, key and central drivers of type 2 inflammation in multiple diseases. In phase 3 QUEST (NCT02414854), add-on dupilumab 200 and 300 mg every 2 weeks reduced severe exacerbations, improved pre-bronchodilator forced expiratory volume in 1 s (FEV1), and was generally well tolerated in patients with uncontrolled moderate-to-severe asthma. This post hoc analysis assessed dupilumab efficacy in subpopulations of patients with type 2 asthma and high-dose inhaled corticosteroids (ICS). METHODS: Adjusted annualized severe exacerbation rates over the treatment period, least squares (LS) mean change from baseline at Week 12 in pre-bronchodilator FEV1, and LS mean change from baseline at Week 24 in 5-item Asthma Control Questionnaire (ACQ-5) scores were analyzed in subgroups of patients receiving high-dose (>500 µg) ICS with baseline blood eosinophils ≥150 cells/µL and/or fractional exhaled nitric oxide ≥25 ppb. Subgroups included allergic phenotype (with/without), comorbid chronic rhinosinusitis and/or nasal polyposis (with/without), pre-bronchodilator FEV1/forced vital capacity (<70%/≥70%), blood eosinophil level, exacerbation history, median baseline pre-bronchodilator FEV1, age at asthma onset (≤40/>40 years), median FEV1 reversibility, body mass index (<30/≥30 kg/m2), and sex. RESULTS: Dupilumab vs placebo reduced exacerbations and improved pre-bronchodilator FEV1 at Week 12 and ACQ-5 at Week 24 across subgroups of patients with type 2 asthma and high-dose ICS at baseline. Dupilumab was also effective in patients receiving medium-dose ICS. CONCLUSION: Dupilumab reduced severe exacerbations and improved lung function and asthma control in subgroups of patients with type 2 asthma and high-dose ICS at baseline. CLINICAL TRIAL REGISTRATION NUMBER: NCT02414854.

Normalisation of airflow limitation in asthma: Post-hoc analyses of TRIMARAN and TRIGGER.

Background: In asthma, persistent airflow limitation (PAL) is associated with poorer control, lung function decline and exacerbations. Using post-hoc analyses we evaluated: the relationship between post-salbutamol PAL at screening, airflow limitation (AL) during 52 weeks treatment with extrafine beclometasone dipropionate/formoterol fumarate/glycopyrronium (BDP/FF/G) versus BDP/FF and the risk of moderate/severe asthma exacerbations. Methods: TRIMARAN and TRIGGER were double-blind studies comparing BDP/FF/G with BDP/FF (TRIMARAN medium-dose ICS; TRIGGER high-dose) in adults with uncontrolled asthma. Patients were subgrouped according to post-salbutamol PAL status at screening, and AL over the 52-week treatment period. Results: Most patients with post-salbutamol PAL at screening had AL at all on-treatment visits (TRIMARAN 62.8%; TRIGGER 66.8%). A significantly higher proportion of patients had normalised airflow on ≥1 follow-up visit when receiving BDP/FF/G than BDP/FF (TRIMARAN 44.1 vs. 33.1% [p = 0.003]; TRIGGER 40.1 vs. 26.0% [p < 0.001]). In patients with post-salbutamol PAL at screening and normalised AL at ≥1 follow-up visit, exacerbation rates were 15% (p = 0.105) and 19% (p = 0.039) lower in TRIMARAN and TRIGGER versus those with AL on all visits. There was a trend to lower exacerbation rates in patients receiving BDP/FF/G than BDP/FF, particularly in patients in whom AL was normalised. Conclusion: In these analyses, AL in asthma was associated with an increased exacerbation incidence. Inhaled triple therapy with extrafine BDP/FF/G was more likely to normalise airflow, and was associated with a trend to a lower exacerbation rate than BDP/FF, particularly in the subgroup of patients in whom treatment was associated with airflow normalisation.ClinicalTrials.gov: TRIMARAN, NCT02676076; TRIGGER, NCT02676089.

Chronic cough in Germany: results from a general-population survey.

BACKGROUND: Chronic cough (CC) which is defined ≥8 weeks is a common condition in clinical practice. However, estimates of prevalence and associated comorbidities in German adults and key subgroups of age and gender are lacking. METHODS: Cross-sectional study based on a representative panel of 15 020 adult subjects of the general population who completed the German National Health and Wellness Survey, reporting CC and questions about comorbidities. Lifetime and 12-month prevalence are presented as unweighted estimates. RESULTS: The lifetime CC prevalence was 6.5% (range across age groups 5.1%-8.3%) and the 12-month prevalence was 4.9% (range 3.7-5.7%). The prevalence of diagnosed CC was 2.8% (range 0.9-4.1%) and the prevalence of persons currently on any prescription to treat CC was 0.6% (range 0.2-1.4%). Respondents who experienced CC were 52.0±17.0 years old, with a higher prevalence in those aged 50 years and older. Persons with CC had higher morbidity scores and were diagnosed with an increased number of comorbidities, most frequently diagnoses of the respiratory system (71.0%), followed by digestive tract disorders (34.0%) and sleep disorders (37.6%). CONCLUSIONS: In a broadly representative sample of German adults, lifetime and 12-month prevalence of CC was greatest in current and former smokers and those older ≥50 years of age. Comorbidities are frequent and may complicate management of these patients.

The impact of moderate and severe asthma exacerbations on quality of life: a post hoc analysis of randomised controlled trial data.

BACKGROUND: This paper reports the duration of moderate and severe exacerbations in patients with house dust mite induced allergic asthma and the impact on patients' quality of life. METHODS: Post-hoc analyses were conducted using data collected during a phase III multi-national trial (MT-04) that investigated time to moderate or severe asthma exacerbation among 485 patients during withdrawal from inhaled corticosteroids. Patient diaries were analysed to ascertain duration of exacerbations. The impact on patients' quality of life was measured by calculating utilities for five health states using the EuroQol-5 Dimension (EQ-5D-3L) and Asthma Quality of Life Questionnaire (AQL-5D). A regression analysis predicted the disutility of moving from 'well controlled asthma' to the other four health states: 'partially controlled asthma', 'uncontrolled asthma', 'moderate exacerbation' and 'severe exacerbation'. RESULTS: Two hundred four patients experienced exacerbations. Moderate and severe exacerbations involved statistically significant reductions in lung function compared to the constant peak expiratory flow observed for patients without exacerbations. Lung function decline occurred for 28 days, decreasing approximately 14 days before an exacerbation followed by a return to baseline over 14 days. Asthma symptoms, the use of short-acting ß2-agonists, and frequency of nocturnal awakening all increased, starting 10-14 days before an exacerbation, and returned to baseline within 10-28 days following exacerbations. Compared to 'well controlled asthma', the disutility of having a 'moderate exacerbation' ranged from - 0.0834 to - 0.0921 (EQ-5D-3L) and from - 0.114 to - 0.121 (AQL-5D); and of having a 'severe exacerbation' from - 0.115 to - 0.163 (EQ-5D-3L) and from - 0.153 to - 0.217 (AQL-5D), depending on the length of the observation period. CONCLUSIONS: The impact of moderate and severe exacerbations in house dust mite induced allergic asthma extends 14 days before and 28 days after the peak exacerbation event. The impact of exacerbations on patients' health-related quality of life (HRQoL) continues long after their occurrence.

Personalized medicine for allergy treatment: Allergen immunotherapy still a unique and unmatched model.

The introduction of personalized medicine (PM) has been a milestone in the history of medical therapy, because it has revolutionized the previous approach of treating the disease with that of treating the patient. It is known today that diseases can occur in different genetic variants, making specific treatments of proven efficacy necessary for a given endotype. Allergic diseases are particularly suitable for PM, because they meet the therapeutic success requirements, including a known molecular mechanism of the disease, a diagnostic tool for such disease, and a treatment blocking the mechanism. The stakes of PM in allergic patients are molecular diagnostics, to detect specific IgE to single-allergen molecules and to distinguish the causative molecules from those merely cross-reactive, pursuit of patient's treatable traits addressing genetic, phenotypic, and psychosocial features, and omics, such as proteomics, epi-genomics, metabolomics, and breathomics, to forecast patient's responsiveness to therapies, to detect biomarker and mediators, and to verify the disease control. This new approach has already improved the precision of allergy diagnosis and is likely to significantly increase, through the higher performance achieved with the personalized treatment, the effectiveness of allergen immunotherapy by enhancing its already known and unique characteristics of treatment that acts on the causes.

Dupilumab is effective in type 2-high asthma patients receiving high-dose inhaled corticosteroids at baseline.

BACKGROUND: Dupilumab blocks the shared receptor component for interleukin (IL)-4/IL-13, key drivers of type 2 inflammation. In phase 2b (NCT01854047) and phase 3 LIBERTY ASTHMA QUEST (NCT02414854), add-on dupilumab 200/300 mg every 2 weeks (q2w) reduced severe exacerbations, improved prebronchodilator (pre-BD) forced expiratory volume in 1 second (FEV1 ) and quality of life measures, and it was generally well tolerated in patients with uncontrolled, persistent (phase 2b), or moderate-to-severe (phase 3) asthma. METHODS: In patients on high-dose inhaled corticosteroids (ICS) with type 2-high asthma (subgroups including baseline blood eosinophils ≥150/300 cells/µL and/or fractional exhaled nitric oxide [FeNO] ≥25 ppb), annualized severe exacerbation rates over the treatment period, changes from baseline in pre-BD FEV1 and asthma control (5-item asthma control questionnaire [ACQ-5]) were analyzed. RESULTS: In high-dose ICS type 2-high subgroups, dupilumab 200/300 mg q2w vs placebo in the phase 2b (24 weeks) and phase 3 (52 weeks) studies significantly reduced severe exacerbations by 55%-69%/57%-60% (all P<.05) and 53%-69%/48%-66% (all P < .001), respectively, except in patients with ≥ 300 eosinophils/µL in phase 2b study (24%/50% (P = .52/0.15). Across subgroups, pre-BD FEV1 improved by 0.18-0.22 L/0.19-0.24 L (all P < .05) and 0.23-0.36 L/0.15-0.25 L (all P < .01) and ACQ-5 scores were reduced by 0.46-0.55/0.47-0.85 (all P < .05) and 0.38-0.50/0.24-0.30 (all P < .05), respectively, except dupilumab 200 mg q2w in phase 2b in patients with FeNO ≥ 25 ppb (0.41; P = .09). Dupilumab was also effective in patients taking medium-dose ICS. CONCLUSION: Dupilumab significantly reduced severe exacerbations and improved lung function and asthma control in patients with type 2-high asthma on high-dose ICS at baseline.

COVID-19 mortality rates in the European Union, Switzerland, and the UK: effect of timeliness, lockdown rigidity, and population density.

BACKGROUND: To date, the European experience with COVID-19 mortality has been different to that observed in China and Asia. We aimed to forecast mortality trends in the 27 countries of the European Union (EU), plus Switzerland and the UK, where lockdown dates and confinement interventions have been heterogeneous, and to explore its determinants. METHODS: We have adapted our predictive model of COVID-19-related mortality, which rested on the observed mortality within the first weeks of the outbreak and the date of the respective lockdown in each country. It was applied in a training set of three countries (Italy, Germany and Spain), and then applied to the EU plus the UK and Switzerland. In addition, we explored the effects of timeliness and rigidity of the lockdown (on a five-step scale) and population density in our forecasts. We report r2, and percent variation of expected versus observed deaths, all following TRIPOD guidance. RESULTS: We identified a homogeneous distribution of deaths, and found a median of 24 days after lockdown adoption to reach the maximum daily deaths. Strikingly, cumulative deaths up to April 25th, 2020 observed in Europe separated countries in three waves, according to the time lockdown measures were adopted following the onset of the outbreak: after a week, within a week, or even prior to the outbreak (r2=0.876). In contrast, no correlation neither with lockdown rigidity nor population density were observed. CONCLUSIONS: The European experience confirms that early, effective interventions of lockdown are fundamental to minimizing the COVID-19 death toll.

COVID-19, asthma, and biological therapies: What we need to know.

Managing patients with severe asthma during the coronavirus pandemic and COVID-19 is a challenge. Authorities and physicians are still learning how COVID-19 affects people with underlying diseases, and severe asthma is not an exception. Unless relevant data emerge that change our understanding of the relative safety of medications indicated in patients with asthma during this pandemic, clinicians must follow the recommendations of current evidence-based guidelines for preventing loss of control and exacerbations. Also, with the absence of data that would indicate any potential harm, current advice is to continue the administration of biological therapies during the COVID-19 pandemic in patients with asthma for whom such therapies are clearly indicated and have been effective. For patients with severe asthma infected by SARS-CoV-2, the decision to maintain or postpone biological therapy until the patient recovers should be a case-by-case based decision supported by a multidisciplinary team. A registry of cases of COVID-19 in patients with severe asthma, including those treated with biologics, will help to address a clinical challenge in which we have more questions than answers.

Clinical Practice of Allergen Immunotherapy for Allergic Rhinoconjunctivitis and Asthma: An Expert Panel Report.

Allergen immunotherapy (AIT) reduces symptoms and medication use associated with allergic rhinitis with or without conjunctivitis and allergic asthma. Although several AIT guidelines exist, there remain unanswered questions about AIT that are relevant to everyday practice. Our objective was to prepare an evidence-based overview addressing the practical aspects of AIT in clinical practice based on published evidence and the experience of international experts in the field. Topics covered include interpretation and translation of clinical trial data into everyday clinical practice (eg, allergen doses and treatment duration), assessment of risk and treatment of local and systemic allergic reactions, recommendations for improvement of AIT guidelines, and identification of appropriate data for seeking regulatory approval, to name a few. Many informational gaps in AIT practice need further evaluation as products and practices evolve.

In patients with severe asthma with eosinophilia in reslizumab clinical trials, high peripheral blood eosinophil levels are associated with low FEV1 reversibility.

BACKGROUND: A post hoc analysis of two randomized, placebo-controlled, Phase 3 trials of intravenous reslizumab, an anti-interleukin-5 (IL-5) biologic for severe eosinophilic asthma. METHODS: Relationships between baseline blood eosinophil levels (EOS), forced expiratory volume in 1 s (FEV1) reversibility to ß2-agonists and treatment outcomes were assessed. RESULTS: Mean baseline FEV1 reversibility was numerically lower among patients with high (≥ 400 cells/µL) versus low baseline EOS. Reslizumab produced clinically significant improvement in FEV1, exacerbation rates and patient-reported outcomes after 52 weeks, including in patients with high EOS and low FEV1 reversibility (≤ 14%) to ß2-agonists at baseline. CONCLUSIONS: Clinical trial eligibility criteria stipulating minimum FEV1 reversibility to ß2-agonists of ≥ 12% might exclude patients who would benefit from treatment with anti-IL-5 biologics.