Comparison of inhaled salbutamol and salmeterol for the treatment of arterial hypoxaemia in anaesthetized horses: a randomized clinical trial.

OBJECTIVE: To compare the efficacy of inhaled salbutamol with salmeterol for the treatment of arterial hypoxaemia in anaesthetized horses. STUDY DESIGN: Prospective, randomized, clinical study. ANIMALS: A total of 108 client-owned horses (American Society of Anesthesiologists status I-V) anaesthetized for elective and emergency procedures. METHODS: Horses were premedicated with acepromazine [intramuscularly 0.1 mg kg-1 or intravenously (IV) 0.05 mg kg-1] and xylazine (0.6 mg kg-1 IV). Midazolam (0.06 mg kg-1 IV) and ketamine (2.2 mg kg-1 IV) were combined to induce anaesthesia, and isoflurane in oxygen/air mixture (inspired oxygen fraction 0.7) was used for maintenance of anaesthesia. Mechanical ventilation was initiated without delay using the following ventilator settings: tidal volume 10 mL kg-1, respiratory rate 8 breaths minute-1, inspiratory-to-expiratory time ratio 1:2, no positive end-expiratory pressure. If arterial blood gas analysis revealed PaO2 < 100 mmHg (13.3 kPa), the administration of either inhaled salbutamol (2 µg kg-1) or salmeterol (0.5 µg kg-1) was randomly assigned Blood gas analysis was repeated 15 and 30 minutes after treatment. The intervention was considered successful when PaO2 after treatment ≥ 1.2 × PaO2 before treatment (i.e. ≥20% increase). PaO2 at 15 and 30 minutes was compared between groups using Mann-Whitney U test; p < 0.05 was considered significant. RESULTS: Of the 108 horses, 60 were administered salbutamol, 65% and 60% responded successfully at 15 and 30 minutes, increasing their initial PaO2 by 38% and 44%, respectively. The other 48 horses were administered salmeterol, 35% responded successfully at 15 and 30 minutes, increasing their initial PaO2 by 3% and 4%, respectively. PaO2 was significantly higher after salbutamol than after salmeterol at 15 and 30 minutes. CONCLUSIONS AND CLINICAL RELEVANCE: Using the described protocol, inhaled salbutamol was more effective than salmeterol in improving PaO2 in anaesthetized horses with value < 100 mmHg (13.3 kPa).

Pharmacokinetic Bioequivalence between Generic and Originator Orally Inhaled Drug Products: Validity of Administration of Doses above the Approved Single Maximum Dose.

Pharmacokinetic bioequivalence of orally inhaled drug products is a critical component of the US FDA's "weight of evidence" approach, and it can serve as the sole indicator of safety and effectiveness of follow-on inhalation products approved in Europe and some other geographic areas. The approved labels of the orally inhaled drug products recommend the maximum number of actuations that can be administered in a single dose on one occasion. This single maximum dose may consist of one or more inhalations depending upon the product. Bioequivalence studies for the inhalation drug product registrations in the US and EU have employed single and multiple actuation doses, in some cases over and above the approved single maximum labeled doses, thus, inconsistent with the approved labeling of the reference products. Pharmacokinetics of inhaled drug products after single and multiple doses may be different, with implications for bioequivalence determined at single and multiple doses. Scientific literature indicates that the relative bioavailability of the Test and Reference products may differ between administrations of doses in one and multiple inhalations. Multiple doses not only alter the pharmacokinetics but also may reduce the sensitivity of the bioassay to actual differences between the Test and Reference product performances. Ability of the pharmacokinetic bioassay to accurately determine the extent of difference between two products may also be substantially reduced at high doses. Therefore, in our opinion, pharmacokinetic bioequivalence to support regulatory approvals of inhalation products at doses above the recommended single maximum dose should be avoided. Furthermore, the bioequivalence of products (if any) established at doses exceeding the approved single maximum doses should be revisited to determine if the products maintain bioequivalence when evaluated at the clinically relevant single maximum doses.

A Simulation Study of the Effect of Clinical Characteristics and Treatment Choice on Reliever Medication Use, Symptom Control and Exacerbation Risk in Moderate-Severe Asthma.

INTRODUCTION: The relationship between immediate symptom control, reliever medication use and exacerbation risk on treatment response and factors that modify it have not been assessed in an integrated manner. Here we apply simulation scenarios to evaluate the effect of individual baseline characteristics on treatment response in patients with moderate-severe asthma on regular maintenance dosing monotherapy with fluticasone propionate (FP) or combination therapy with fluticasone propionate/salmeterol (FP/SAL) or budesonide/formoterol (BUD/FOR). METHODS: Reduction in reliever medication use (puffs/24 h), change in symptom control scores (ACQ-5), and annualised exacerbation rate over 12 months were simulated in a cohort of patients with different baseline characteristics (e.g. time since diagnosis, asthma control questionnaire (ACQ-5) symptom score, smoking status, body mass index (BMI) and sex) using drug-disease models derived from large phase III/IV clinical studies. RESULTS: Simulation scenarios show that being a smoker, having higher baseline ACQ-5 and BMI, and long asthma history is associated with increased reliever medication use (p < 0.01). This increase correlates with a higher exacerbation risk and higher ACQ-5 scores over the course of treatment, irrespective of the underlying maintenance therapy. Switching non-responders to ICS monotherapy to combination therapy after 3 months resulted in immediate reduction in reliever medication use (i.e. 1.3 vs. 1.0 puffs/24 h for FP/SAL and BUD/FOR, respectively). In addition, switching patients with ACQ-5 > 1.5 at baseline to FP/SAL resulted in 34% less exacerbations than those receiving regular dosing BUD/FOR (p < 0.01). CONCLUSIONS: We have identified baseline characteristics of patients with moderate to severe asthma that are associated with greater reliever medication use, poor symptom control and higher exacerbation risk. Moreover, the effects of different inhaled corticosteroid (ICS)/long-acting beta agonist (LABA) combinations vary significantly when considering long-term treatment performance. These factors should be considered in clinical practice as a basis for personalised management of patients with moderate-severe asthma symptoms.

In this study we looked at how different factors affect the response to asthma treatment in people with moderate to severe asthma who are taking regular medication. Specifically, we wanted to quantify how much asthma duration, differences in the degree of symptom control and lung function, as well as smoking habit, body weight, and sex influence how well someone responds to regular maintenance therapy. Using computer simulations based on models obtained from data in a large patient population with moderate­severe asthma, we explored scenarios that reflect real-life management of patients undergoing treatment with inhaled corticosteroids alone or in combination with long-acting beta agonists over a 12-month period. We looked at how much reliever inhaler they use, how well they rate their asthma control, and how often they have asthma attacks. By considering these results together, we evaluated how well the treatments work on ongoing symptoms and/or reduce the risk of future asthma attacks. Our simulations showed that smokers, people with higher asthma symptom scores, who are obese, and have a longer history of asthma tend to use their reliever inhalers more often. This was linked to a higher risk of having asthma attacks and worse symptom control. Switching those patients who do not respond well to their initial treatment with corticosteroid to combination therapy reduced how much reliever inhaler they need. Also, the effects of fluticasone propionate/salmeterol combination therapy were greater than budesonide/formoterol. In conclusion, our study found that certain patient characteristics can predict how well someone responds to asthma treatment.

Preclinical evaluation of novel synthesised nanoparticles based on tyrosine poly(ester amide) for improved targeted pulmonary delivery.

Fixed dose combinations (FDCs) incorporating two or three medicines in a single inhaler have been created to enhance patient compliance and hence clinical outcomes. However, the development of dry powder inhalers (DPIs), particularly for FDCs, faces challenges pertinent to formulation uniformity and reproducibility. Therefore, this project aimed to employ nanotechnology to develop a FDC of DPIs for market-leading medicines-fluticasone propionate (FP) and salmeterol xinafoate (SAL)-for asthma management. Nanoaggregates were prepared using a novel biocompatible and biodegradable poly(ester amide) based on the amino acid tyrosine, utilising a one-step interfacial polymerisation process. The produced tyrosine poly (ester amide) drug-loaded nanoparticles were evaluated for content uniformity, PSA, FTIR, TEM, DSC, XRD and aerodynamic performance (in vitro and in vivo). The optimised formulation demonstrated high entrapment efficiency- > 90%. The aerodynamic performance in terms of the emitted dose, fine particle fraction and respirable dose was superior to the carrier-based marketed product. In-vivo studies showed that FP (above the marketed formulation) and SAL reached the lungs of mice in a reproducible manner. These results highlight the superiority of novel FDC FP/SAL nanoparticles prepared via a one-step process, which can be used as a cost-effective and efficient method to alleviate the burden of asthma.

Pharmacokinetic Models for Inhaled Fluticasone Propionate and Salmeterol Xinafoate to Quantify Batch-to-Batch Variability.

Advair Diskus is an essential treatment for asthma and chronic obstructive pulmonary disease. It is a dry powder inhaler with a combination of fluticasone propionate (FP) and salmeterol xinafoate (SX). However, the pharmacokinetics (PK) batch-to-batch variability of the reference-listed drug (RLD) hindered its generic product development. This work developed the PK models for inhaled FP and SX that could represent potential batch variability. Two batches each of the reference and the test product (R1, R2, T1, T2) of Advair Diskus (100 µg FP/50 µg SX inhalation) were administered to 60 healthy subjects in a 4-period, 4-sequence crossover study. The failure of the bioequivalence (BE) between R1 and R2 confirmed the high between-batch variability of the RLD. Non-linear mixed effect modeling was used to estimate the population mean PK parameters for each batch. For FP, a 2-compartment model with a sequential dual zero-order absorption best described the PK profile. For SX, a 2-compartment model with a first-order absorption model best fit the data. Both models were able to capture the plasma concentration, the maximum concentration, and the total exposure (AUCinf) adequately for each batch, which could be used to simulate the BE study in the future. In vitro properties were also measured for each batch, and the batch with a higher fraction of the fine particle (diameter < 1 µm, < 2 µm) had a higher AUCinf. This positive correlation for both FP and SX could potentially assist the batch selection for the PK BE study.

Comparative Efficacy of Budesonide/Formoterol Versus Fluticasone/Salmeterol in Patients With Moderate-to-Severe Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis.

BACKGROUND/OBJECTIVE: To compare the efficacy of budesonide/formoterol (BF) versus fluticasone/salmeterol (FS) in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD). METHODS: The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for studies comparing BF versus FS in the treatment of COPD from inception to July 17, 2023. Outcomes, including exacerbations, hospitalizations, pneumonia, emergency department (ED) visits for COPD, length of hospitalization, and number of exacerbations, were compared using risk ratio (RR) with corresponding 95% confidence interval (CI) or weighted mean difference (WMD) with 95% CI. All statistical analyses were performed using Stata version 12.0. RESULTS: Ten studies comprising a total of 136,369 participants were included. Compared with those treated with FS, patients with COPD treated with BF experienced a reduced number of exacerbations (RR 0.91 [95% CI 0.83-1.00]; p = 0.040), hospitalizations (RR 0.77 [95% CI 0.67-0.88]; p < 0.001), and frequency of pneumonia (RR 0.77 [95% CI 0.64-0.92]; p = 0.05). However, no significant difference was observed between BF and FS in terms of ED visits for COPD (RR 0.87 [95% CI 0.69-1.10]; p = 0.243), length of hospitalization (WMD -0.18 [95% CI -0.62-0.27]; p = 0.437), and number of exacerbations (WMD -0.06 [95% CI -0.28-0.16]; p = 0.602). Notably, no significant heterogeneity was noted in length of hospitalization between the two groups, whereas clear heterogeneity was observed in other outcomes (I2 > 50%, p < 0.05). CONCLUSION: Compared with FS, BF therapy appears to be a more promising treatment strategy for patients with moderate-to-severe COPD; however, this should be verified in further high-quality studies.

Umeclidinium plus vilanterol versus fluticasone propionate plus salmeterol for chronic obstructive pulmonary disease: a meta-analysis of randomized, controlled trials.

PURPOSE: Umeclidinium plus vilanterol (UMEC/VI) is an inhaled long-acting muscarinic antagonist/long-acting beta2-agonist (LAMA/LABA), recently approved as once-daily maintenance therapy for chronic obstructive pulmonary disease (COPD). This meta-analysis aims to assess the efficacy and safety of UMEC/VI compared with fluticasone propionate plus salmeterol (FP/SAL). METHODS: A systematic search was conducted by a trained medical research librarian across MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Chinese Biomedical Literature Database (CBM) for randomized controlled trials comparing UMEC/VI with FP/SAL in COPD patients. Two reviewers independently assessed the risk of bias and extracted data. The primary outcome was 0-24 h weighted mean (wm) forced expiratory volume in the first second (FEV1), trough FEV1. The secondary outcomes were other lung functions, symptoms, quality of life, and safety. RESULTS: Three studies with 2119 patients were included in the meta-analysis. UMEC/VI showed improvement in 0-24 h wm FEV1 (mean difference (MD) 0.08 L, 95% confidence interval (CI) 0.06 to 0.10, P < 0.01, moderate quality) and trough FEV1 (MD 0.09 L, 95% CI 0.07 to 0.11, P < 0.01, moderate quality) in comparison with FP/SAL. UMEC/VI statistically significantly improved all other lung functions compared with FP/SAL. However, there were no significant differences between UMEC/VI and FP/SAL in rescue-medication use, symptomatic endpoints, and health outcomes. UMEC/VI also demonstrated fewer drug-related adverse effects (risk ratio 0.47, 95% CI 0.27 to 0.82, P = 0.01, low quality). CONCLUSIONS: UMEC/VI, when compared with FP/SAL, demonstrated significant improvements in lung functions with fewer drug-related adverse effects. However, the conclusion was limited by the scarcity of studies and long-term trials.

Regional lung targeting with a fluticasone/salmeterol aerosol using a bolus breath hold method of the PreciseInhale® system: A first evaluation in humans.

BACKGROUND: In development of inhaled drugs- and formulations the measured concentration in the systemic circulation is often used as a surrogate for local dosimetry in the lungs. To further elucidate regional differences in the fate of drugs in the lungs, different aerodynamic sizes of aerosols have been used to target major airway regions. An alternative approach to achieve regional targeting of aerosols, is to use a defined aerosol bolus together with a bolus breath hold strategy. A small volume of test aerosol is intercalated and stopped at different penetration depths, to achieve increased drug deposition at chosen lung locations. Drug permeation from the lung regions is then investigated by repeatedly sampling venous blood from the systemic circulation. The PreciseInhale® (PI) exposure platform was developed to allow generation of aerosols from different sources, including clinical inhalers, into a holding chamber, for subsequent use with alternative exposure modules in vitro and in vivo. In the current first-in-human study was investigated the feasibility of a new clinical exposure module added to the PI system. By extracting aerosol puffs from a medical inhaler for subsequent delivery to volunteers, it was possible to administer whole lung exposures, as well as regional targeting exposures. METHODS: Aerosols containing 250 µg/25 µg fluticasone propionate (FP)/salmeterol xinafoate (SMX) were automatically actuated and extracted from the pressurized Metered Dose Inhaler (pMDI) Evohaler Seretide forte into the PI system's holding chamber, then administered to the healthy volunteers using controlled flowrate and volume exposure cycles. Two main comparisons were made by measuring the systemic PK response: I. One label dose directly from the inhaler to the subject was compared to the same dose extracted from the pMDI into the PI system and then administered to the subject. II A small aerosol bolus at a penetration level in the central airways was compared to a small aerosol bolus at a penetration level in the peripheral lung. RESULTS AND CONCLUSIONS: When one inhaler dose was administered via the PI system, the absorbed dose, expressed as AUC24, was approximately twice as high and the CV was less than half, compared to direct inhalation from the same pMDI. Bolus breath hold targeting of drugs from the same aerosol mixture to the peripheral lung and the central airways showed a difference in their appearance in the systemic circulation. Normalized to the same deposited dose, SMX had a 57 % higher Cmax in the peripheral lung compared to the central airways. However, from 6 to 24 h after dosing the systemic concentrations of SMX from both regions were quite similar. FP had parallel concentrations curves with a 23 % higher AUC24 in the peripheral lung with no noticeable elevation around Cmax. The permeability of these two substances from similar sized aerosols was indeed higher in the thinner air/blood barriers of the peripheral lung compared to the central airways, but differences as measured on the venous side of the circulation were not dramatic. In conclusion, the PI system provided better control of actuation, aspiration, and dispensation of aerosols from the clinical inhaler and thereby delivered higher quality read outs of pharmacokinetic parameters such as tmax, Cmax, and AUC. Improved performance, using PI system, can likely also be employed for studying regional selectivity of other responses in the lungs, for use in drug development.

Efficacy and safety of fluticasone propionate/salmeterol and fluticasone propionate monotherapy in step-up treatment of childhood asthma: A systematic review and meta-analysis.

BACKGROUND: Asthma is a chronic respiratory disease that affects millions of children worldwide and can impair their quality of life and development. Inhaled glucocorticoids are the mainstay of asthma treatment, but some children require step-up therapy with additional drugs to achieve symptom control. Fluticasone propionate and salmeterol (FSC) has been shown to reduce asthma exacerbations and improve lung function in adults. However, the evidence for its efficacy and safety in children is limited. OBJECTIVE: This study aims to provide a comprehensive basis for treatment selection by summarizing existing clinical randomized controlled trials (RCTs) on the efficacy of FSC compared to fluticasone propionate (FP) monotherapy in children with asthma who require step-up treatment. METHODS: Five online databases and three clinical trial registration platforms were systematically searched. The effect size and corresponding 95% confidence interval (CI) were calculated based on the heterogeneity among the included studies. RESULTS: Twelve RCTs were identified and a total of 9, 859 patients were involved. The results of the meta-analysis revealed that the use of FSC was associated with a greater reduction in the incidence of asthma exacerbations than FP alone when the dose of FP was the same or when the duration of treatment exceeded 12 weeks. In addition, FSC resulted in a greater proportion of time with asthma-free and without the use of albuterol compared to FP alone when the duration of treatment exceeded 12 weeks. No significant differences were observed between FSC and FP alone in the incidence of drug-related adverse events and other adverse events. CONCLUSION: Both FSC and FP alone are viable options for the initial selection of step-up treatment in asthmatic children. While, FSC treatment demonstrates a greater likelihood of reducing asthma exacerbations which is particularly important for reducing the personnel, social and economic burden in children requiring step-up asthma treatment.

Cost-utility analysis of budesonide/formoterol powder inhalation versus salmeterol/fluticasone powder inhalation for asthma in adolescents / 药物流行病学杂志

Objective To evaluate the cost-effectiveness of budesonide/formoterol powder inhalation(BF)versus salmeterol/fluticasone powder inhalation(SF)for the treatment of persistent asthma in adolescents,and to provide economic evidence and reference for clinical medication and decision-making.Methods From perspective of Chinese healthcare,a Markov model was established based on a prospective cohort study conducted by Shanghai Fudan University Affiliated Minhang Hospital.The cycle length was 7 days,and the time horizon was 6 years.A discount rate of 5％per year was applied.Clinical parameters including asthma acute exacerbation,treatment costs,and health utility values were obtained from relevant literature.The primary outcomes were direct medical costs,quality-adjusted life-years(QALYs),and incremental cost-utility ratio(ICUR).Cost-utility analysis was performed using TreeAge Pro 2022.The one-way sensitivity analysis and probabilistic sensitivity analysis were conducted to validate the robustness of the basic analysis results.Results Compared with SF group,BF group contributed to an incremental QALYs of 0.002 5 and reduced the cost by 7 043.93 yuan,which implied that BF group was a dominating treatment.Results of one-way sensitivity analysis showed that SF price,BF price and Hazard ratio of asthma acute exacerbation(BF vs.SF)were the main sensitivity factors of model.Probabilistic sensitivity analysis demonstrated the probability of BF being cost-effective was about 80％within the willingness to pay threshold of 257 100 yuan/QALY.Conclusions It was found out in this study that BF was a more cost-effective option for the adolescents with persistent asthma compared with SF.

Efficacy of ß2-adrenergic receptor agonist combined with corticosteroid in the treatment of children with cough variant asthma.

BACKGROUND: Cough variant asthma (CVA) is one of the most common respiratory diseases in children, which has a serious impact on the quality of life and daily activities of children. For severe CVA, immunomodulatory drugs are needed. AIM: To evaluate the efficacy of salmeterol combined with budesonide in the treatment of pediatric CVA. METHODS: 130 children with CVA from January 2020 to December 2022 were prospectively selected and randomly divided into an observation group (salmeterol combined with budesonide) and a control group (budesonide combined with a placebo). Compare the clinical efficacy of two groups before and after intervention. The evaluation parameters include cough frequency score, nocturnal cough arousal, and lung function indicators. Serum inflammatory markers, immune function markers and airway anatomical indicators were also measured. RESULTS: After the intervention, the total effective rate of the observation group was significantly higher than that of the control group, and the cough frequency score and the night cough wake rate of the observation group were lower than that of the control group, with a statistically significant difference. In addition, the changes of lung function indicators, serum markers and immune function markers in the observation group were better than those in the control group. CONCLUSION: The clinical efficacy of salmeterol combined with Budesonide in the treatment of CVA is better than that of Budesonide alone.

Giant lung cavity due to three different pathogens in a patient receiving inhaled salmeterol plus fluticasone propionate for asthma.

INTRODUCTION: High-dose and long-term use of inhaled corticosteroids may cause systemic and local side effects such as opportunistic infections. Here we report a patient with asthma who developed a giant cavity in the lung while using inhaled salmeterol plus fluticasone propionate. CASE STUDY: A 57-year-old female patient presented with a three-week history of cough, hemoptysis, and dyspnea. She had a diagnosis of asthma for 4 years and was using an inhaled salmeterol plus fluticasone treatment intermittently for 2 years. A giant cavity was detected in the patient's chest X-ray. As a result of further investigations, three different microorganisms were isolated from the samples of sputum, bronchial lavage and lung biopsy. RESULTS: Staphylococcus aureus was the first microorganism that was isolated from the sputum and the bronchial lavage. Afterwards, Candida albicans was detected in both the bronchial lavage fluid and the histologic examination of the tissue samples obtained by percutaneous lung biopsy. Appropriate antibiotics and antifungals were prescribed. Moderate clinical and radiological response to the treatment was obtained. During the outpatient follow-up, Mycobacterium tuberculosis growth which was sensitive to all of the major anti-tuberculosis drugs was reported in the mycobacterial culture, and the patient was started on anti-tuberculosis treatment. CONCLUSION: Tuberculosis and other opportunistic infections are a potential consequences of inhaled corticosteroids. Clinicians overseeing such patients need to be vigilant about the need for timely investigations about tuberculosis before and during prescribing medications containing inhaled corticosteroids.

Bronchodilator reversibility testing in morbidly obese non-smokers: fluticasone/salmeterol efficacy versus salbutamol bronchodilator.

A positive response in reversibility testing is widely used to diagnose patients with airway limitations. However, despite its simple procedure, it doesn't accurately reflect the exact airway irreversibility. This study aimed to investigate the efficacy of a bronchodilation reversibility test using salbutamol and fluticasone/salmeterol combination in obese non-smoker subjects.The study included patients without a history of obstructive lung disease or bronchodilators. A sub-classification of patients based on body mass index (BMI) was carried out into normal (< 24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (BMI ≥ 30). Spirometry measurements were performed before and after salbutamol or fluticasone/salmeterol administration.The study included 415 (49.9% male) patients with a mean age of 40.92 ± 10.86 years. Obese subjects showed a high prevalence of restrictive patterns (23.4%), with non-significantly lower spirometric values compared to normal and overweight subjects (p > 0.05). The magnitude of bronchodilation, as identified by spirometry, following fluticasone/salmeterol was higher in all participants, with a significant increase in obese subjects with a p-value of 0.013, 0.002, and 0.035 for FEV1, FEV1% predicted, and FEV1/FVC, respectively.Fluticasone/salmeterol combination increases FEV1, FEV1% of predicted, and FEV1/FVC ratio than the conventional test using salbutamol inhaler, and it can be a potential candidate for assessment of airway obstruction using reversibility test, especially among the obese population.

Impaired vascular ß-adrenergic relaxation in spontaneously hypertensive rats: The differences between conduit and resistance arteries.

It was suggested that impaired ß-adrenergic relaxation in spontaneously hypertensive rats (SHR) might contribute to their high blood pressure (BP). Our study was focused on isoprenaline-induced dilatation of conduit femoral or resistance mesenteric arteries and on isoprenaline-induced BP reduction in SHR and Wistar-Kyoto rats (WKY). We confirmed decreased ß-adrenergic relaxation of SHR femoral arteries due to the absence of its endothelium-independent component, whereas endothelium-dependent component of ß-adrenergic smooth muscle relaxation was similar in both strains. Conversely, isoprenaline-induced relaxation of resistance mesenteric arteries was similar in both strains and this was true for endothelium-dependent and endothelium-independent components. We observed moderately reduced sensitivity of SHR mesenteric arteries to salmeterol (ß2-adrenergic agonist) and this strain difference disappeared after endothelium removal. However, there was no difference in mesenteric arteries relaxation by dobutamine (ß1-adrenergic agonist) which was independent of endothelium. The increasing isoprenaline doses elicited similar BP decrease in both rat strains, although BP sensitivity to isoprenaline was slightly decreased in SHR. The blockade of cyclooxygenase (indomethacin) and NO synthase (L-NAME) further reduced BP sensitivity to isoprenaline in SHR. On the other hand, salmeterol elicited similar BP decrease in both strains and the blockade of cyclooxygenase and NO synthase increased BP sensitivity to salmeterol in SHR as compared to WKY. In conclusion, attenuated ß-adrenergic vasodilatation of conduit arteries of SHR but similar ß-adrenergic relaxation of resistance mesenteric arteries from WKY and SHR and their similar BP response to ß-adrenergic agonists do not support major role of altered ß-adrenergic vasodilatation for high BP in genetic hypertension.

Understanding the Clinical Implications of Individual Patient Characteristics and Treatment Choice on the Risk of Exacerbation in Asthma Patients with Moderate-Severe Symptoms.

INTRODUCTION: The assessment of future risk has become an important feature in the management of patients with asthma. However, the contribution of patient-specific characteristics and treatment choices to the risk of exacerbation is poorly understood. Here we evaluated the effect of interindividual baseline differences on the risk of exacerbation and treatment performance in patients receiving regular maintenance doses of inhaled corticosteroids (ICS) or ICS/long-acting beta-agonists (LABA) combination therapy. METHODS: Exacerbations and changes to asthma symptoms 5-item Asthma Control Questionnaire (ACQ-5) were simulated over a 12-month period using a time-to-event and a longitudinal model developed from phase III/IV studies in patients with moderate-severe asthma (N = 16,282). Simulations were implemented to explore treatment performance across different scenarios, including randomised designs and real-world settings. Treatment options included regular dosing with ICS monotherapy [fluticasone propionate (FP)] and combination therapy [fluticasone propionate/salmeterol (FP/SAL) or budesonide/formoterol (BUD/FOR)]. Exacerbation rate was analysed using the log-rank test. The cumulative incidence of events was summarised stratified by treatment. RESULTS: Being a woman, smoker, having higher baseline ACQ-5 and body mass index (BMI) and lower forced expiratory volume in the first second (FEV1) are associated with increased exacerbation risk (p < 0.01). This risk is bigger in winter because of the seasonal variation effect. Across the different scenarios, the use of FP/SAL resulted in a 10% lower annual incidence of exacerbations relative to FP or regular dosing BUD/FOR, independently of baseline characteristics. Similar differences in the annual incidence of exacerbations were also observed between treatments in obese patients (BMI ≥ 25-35 kg/m2) (p < 0.01) and in patients who do not achieve symptom control on FP monotherapy. CONCLUSIONS: Individual baseline characteristics and treatment choices affect future risk. Achieving comparable levels of symptom control whilst on treatment does not imply comparable risk reduction, as shown by the lower exacerbation rates in FP/SAL vs. BUD/FOR-treated patients. These factors should be considered as a basis for personalised clinical management of patients with moderate-severe asthma.

The goal of this project was to demonstrate that individual baseline characteristics can affect the risk of exacerbation as well as the overall treatment response in patients receiving regular maintenance doses of inhaled corticosteroids, given as monotherapy or in combination with long-acting beta-agonists. Using computer simulations based on a drug­disease model previously developed from a large pool of patients with moderate­severe asthma symptoms (N = 16,282), we describe how demographic and clinical baseline patient characteristics at the time of treatment start correlate with the risk of exacerbation. Our results indicate that poor symptom control, limited lung function, obesity, smoking and sex are associated with significant increase in the incidence of asthma attacks. Such an effect is augmented in winter because of the contribution of seasonal variation. This analysis also allowed us to assess how different treatments modify or reduce the annual incidence of moderate to severe attacks. In addition, simulated scenarios showed that combination therapy with fluticasone propionate/salmeterol results in 10% fewer asthma attacks relative to budesonide/formoterol combination therapy. Such a difference may be associated with corticosteroid-specific properties, which vary between inhaled corticosteroids. Consequently, even though comparable level of immediate relief and symptom control may be achieved whilst on treatment, these effects do not imply the same long-term reduction in the risk of exacerbation. These factors should be considered as a basis for personalised clinical management of patients with moderate­severe asthma.

Modelling ASthma TrEatment Responses (MASTER): Effect of individual patient characteristics on the risk of exacerbation in moderate or severe asthma: A time-to-event analysis of randomized clinical trials.

AIMS: There is limited understanding of how clinical and demographic characteristics are associated with exacerbation risk in patients with moderate-to-severe asthma, and how these factors correlate with symptom control and treatment response. Here we assess the relationship between baseline characteristics and exacerbation risk during regular dosing with inhaled corticosteroids (ICS) monotherapy or in combination with long-acting beta2-agonists (ICS/LABA) in clinical trial patients with varying levels of symptom control, as assessed by the asthma control questionnaire (ACQ-5). METHODS: A time-to-event model was developed using pooled patient data (N = 16 282) from nine clinical studies [Correction added on 26 July 2023, after first online publication: The N value in the preceding sentence has been corrected in this version.]. A parametric hazard function was used to describe the time-to-first exacerbation. Covariate analysis included the assessment of the effect of seasonal variation, clinical and demographic baseline characteristics on baseline hazard. Predictive performance was evaluated by standard graphical and statistical methods. RESULTS: An exponential hazard model best described the time-to-first exacerbation in moderate-to-severe asthma patients. Body mass index, smoking status, sex, ACQ-5, % predicted forced expiratory volume over 1 s (FEV1 p) and season were identified as statistically significant covariates affecting baseline hazard irrespective of ICS or ICS/LABA use. Fluticasone propionate/salmeterol (FP/SAL) combination therapy resulted in a significant reduction in the baseline hazard (30.8%) relative to FP monotherapy. CONCLUSIONS: Interindividual differences at baseline and seasonal variation affect the exacerbation risk independently from drug treatment. Moreover, it appears that even when a comparable level of symptom control is achieved in a group of patients, each individual may have a different exacerbation risk, depending on their baseline characteristics and time of the year. These findings highlight the importance of personalized interventions in moderate-to-severe asthma patients.

Safety and Effectiveness of As-Needed Formoterol in Asthma Patients Taking Inhaled Corticosteroid (ICS)-Formoterol or ICS-Salmeterol Maintenance Therapy.

BACKGROUND: As-needed low-dose inhaled corticosteroid (ICS)-formoterol reliever is recommended in patients with asthma prescribed maintenance ICS-formoterol. Clinicians often ask whether ICS-formoterol reliever can be used with other maintenance ICS-long-acting ß2-agonists. OBJECTIVE: To evaluate the safety and effectiveness of as-needed formoterol in patients taking maintenance ICS-formoterol or ICS-salmeterol from the RELIEF study. METHODS: RELIEF (SD-037-0699) was a 6-month, open-label study that randomized 18,124 patients with asthma to as-needed formoterol 4.5 µg or salbutamol 200 µg on top of maintenance therapy. This post hoc analysis included patients on maintenance ICS-formoterol or ICS-salmeterol (n = 5436). The primary safety outcome was a composite of serious adverse events (SAEs) and/or adverse events leading to discontinuation (DAEs); the primary effectiveness outcome was time-to-first exacerbation. RESULTS: For both maintenance groups and both relievers, similar numbers of patients had ≥1 SAE and/or DAE. In patients taking maintenance ICS-salmeterol, but not ICS-formoterol, significantly more non-asthma-related and nonserious DAEs occurred with as-needed formoterol versus as-needed salbutamol (P = .0066 and P = .0034, respectively). In patients taking maintenance ICS-formoterol, there was a significantly lower risk in time-to-first exacerbation with as-needed formoterol versus as-needed salbutamol (hazard ratio [HR]: 0.82, 95% confidence interval [CI]: 0.70, 0.95; P = .007). In patients taking ICS-salmeterol maintenance, time-to-first exacerbation was not significantly different between treatment arms (HR: 0.95, 95% CI: 0.84, 1.06; P = .35). CONCLUSIONS: As-needed formoterol significantly reduced exacerbation risk compared with as-needed salbutamol when added to maintenance ICS-formoterol, but not to maintenance ICS-salmeterol. More DAEs were seen with ICS-salmeterol maintenance therapy plus as-needed formoterol. Further research is needed to assess whether this is relevant to as-needed combination ICS-formoterol.