Influence of ethnicity on response to asthma drugs

Toward Personalized Salbutamol Therapy: Validating Virtual Patient-Derived Population Pharmacokinetic Model with Real-World Data

Interindividual variability, influenced by patient-specific factors including age, weight, gender, race, and genetics, among others, contributes to variations in therapeutic response. Population pharmacokinetic (popPK) modeling is an essential tool for pinpointing measurable factors affecting dose-concentration relationships and tailoring dosage regimens to individual patients. Herein, we developed a popPK model for salbutamol, a short-acting β2-agonist (SABA) used in asthma treatment, to identify key patient characteristics that influence treatment response. To do so, synthetic data from physiologically-based pharmacokinetic (PBPK) models was employed, followed by an external validation using real patient data derived from an equivalent study. Thirty-two virtual patients were included in this study. A two-compartment model, with first-order absorption (no delay), and linear elimination best fitted our data, according to diagnostic plots and selection criteria. External validation demonstrated a strong agreement between individual predicted and observed values. The incorporation of covariates into the basic structural model identified a significant impact of age on clearance (Cl) and intercompartmental clearance (Q); gender on Cl and the constant rate of absorption (ka); race on Cl; and weight on Cl in the volume of distribution of the peripheral compartment (V2). This study addresses critical challenges in popPK modeling, particularly data scarcity, incompleteness, and homogeneity, in traditional clinical trials, by leveraging synthetic data from PBPK modeling. Significant associations between individual characteristics and salbutamol's PK parameters, here uncovered, highlight the importance of personalized therapeutic regimens for optimal treatment outcomes.

The impact of genomic variants on patient response to inhaled bronchodilators: a comprehensive update

INTRODUCTION

The bronchodilator response (BDR) depends on many factors, including genetic ones. Numerous single nucleotide polymorphisms (SNPs) influencing BDR have been identified. However, despite several studies in this field, genetic variations are not currently being utilized to support the use of bronchodilators.

AREAS COVERED

In this narrative review, the possible impact of genetic variants on BDR is discussed.

EXPERT OPINION

Pharmacogenetic studies of β₂-agonists have mainly focused on ADRB2 gene. Three SNPs, A46G, C79G, and C491T, have functional significance. However, other uncommon variants may contribute to individual variability in salbutamol response. SNPs haplotypes in ADRB2 may have a role. Many variants in genes coding for muscarinic ACh receptor (mAChR) have been reported, particularly in the M₂ and, to a lesser degree, M₃ mAChRs, but no consistent evidence for a pharmacological relevance of these SNPs has been reported. Moreover, there is a link between SNPs and ethnic and/or age profiles regarding BDR. Nevertheless, replication of pharmacogenetic results is limited and often, BDR is dissociated from what is expected based on SNP identification. Pharmacogenetic studies on bronchodilators must continue. However, they must integrate data derived from a multi-omics approach with epigenetic factors that may modify BDR.

Uncovering Outcome Disparities of β2 Adrenergic Agonists in Blacks: A Systematic Review

PURPOSE

Outcome differences driven by variation in Blacks' biologic response to treatment may contribute to persistent racial disparities in asthma morbidity and mortality. This review assessed systematic variation in β₂ agonist treatment outcomes among Blacks compared to other groups.

METHODS

We conducted a systematic review of studies reporting differential response to β₂ agonists among Blacks, including studies identifying pharmacogenetic variants.

RESULTS

Of 3158 papers, 20 compared safety or efficacy of β₂ agonists among Blacks as compared with other subgroups. Six papers evaluating efficacy of short-acting β₂ agonists (SABA) found similar or improved results among Blacks compared with other groups, while one small study found reduced response to SABA therapy among Blacks. Reports of safety and efficacy of long-acting β₂ agonists (LABA) indicated similar results among Blacks in four papers, while four reports found reduced safety among Blacks, as compared with other groups. Four papers assessed genomic variation and relative treatment response in Blacks, with two finding significant effects of the p.Arg16Gly variant in ADRB2 on β₂ agonist response and one finding significant gene-gene IL6/IL6R interaction effects on albuterol response.

CONCLUSIONS

Evidence suggests the potential for differences in β₂ agonist outcomes among Blacks compared with other groups. This literature, however, remains small and significantly underpowered for substantive conclusions. There are notable opportunities for adequately-powered investigations exploring safety and efficacy of β₂ agonists among Blacks, including pharmacogenomic modifiers of response.

The modification of three vulnerability theories to assist nursing practice for school-age children with severe asthma

PURPOSE

Severe asthma is an inflammatory illness associated with adverse health outcomes and behaviors in children, such as decreased quality of life, impaired sleep, and increased medical costs and morbidity.

CONCLUSIONS

Children with severe asthma frequently exhibit a cycle of health and behaviors which contribute to these adverse health outcomes, consisting of decreased physical activity, increased stress, and increased airway inflammation and asthma exacerbations. School-age children, in particular, are a vulnerable population because they not only rely on others for their care but also suffer from a chronic illness and are at risk for unequal healthcare access and health outcomes.

PRACTICE IMPLICATIONS

Currently, there is no one nursing theory that adequately addresses the vulnerability, cycle of health and behaviors, and adverse health outcomes of children with severe asthma. By integrating key concepts from three vulnerability theories and presenting a modified conceptual framework, this paper aims to demonstrate how the use of this new conceptual framework may assist nurses in evaluating the unique needs of school-age children with severe asthma to provide best practices and develop appropriate interventions.

Efficacy And Safety Of Glycopyrrolate/Formoterol Fumarate Metered Dose Inhaler (GFF MDI) Formulated Using Co-Suspension Delivery Technology In Chinese Patients With COPD

Background

Glycopyrrolate/formoterol fumarate metered dose inhaler (GFF MDI) is a long-acting muscarinic antagonist/long-acting β₂-agonist fixed-dose combination therapy delivered by MDI, formulated using innovative co-suspension delivery technology. The PINNACLE-4 study evaluated the efficacy and safety of GFF MDI in patients with moderate-to-very severe chronic obstructive pulmonary disease (COPD) from Asia, Europe, and the USA. This article presents the results from the China subpopulation of PINNACLE-4.

Methods

In this randomized, double-blind, placebo-controlled, parallel-group Phase III study (NCT02343458), patients received GFF MDI 18/9.6 µg, glycopyrrolate (GP) MDI 18 µg, formoterol fumarate (FF) MDI 9.6 µg, or placebo MDI (all twice daily) for 24 weeks. The primary endpoint was change from baseline in morning pre-dose trough forced expiratory volume in 1 second at Week 24. Secondary lung function endpoints and patient-reported outcome measures were also assessed. Safety was monitored throughout the study.

Results

Overall, 466 patients from China were included in the intent-to-treat population (mean age 63.6 years, 95.7% male). Treatment with GFF MDI improved the primary endpoint compared to GP MDI, FF MDI, and placebo MDI (least squares mean differences: 98, 104, and 173 mL, respectively; all P≤0.0001). GFF MDI also improved daily total symptom scores and time to first clinically important deterioration versus monocomponents and placebo MDI, and Transition Dyspnea Index focal score versus placebo MDI. Rates of treatment-emergent adverse events were similar across the active treatment groups and slightly higher in the placebo MDI group.

Conclusion

GFF MDI improved lung function and daily symptoms versus monocomponents and placebo MDI and improved dyspnea versus placebo MDI. All treatments were well tolerated with no unexpected safety findings. Efficacy and safety results were generally consistent with the global PINNACLE-4 population, supporting the use of GFF MDI in patients with COPD from China.

Population-scale genomics-Enabling precision public health

The current excitement for affordable genomics technologies and national precision medicine initiatives marks a turning point in worldwide healthcare practices. The last decade of global population sequencing efforts has defined the enormous extent of genetic variation in the human population resulting in insights into differential disease burden and response to therapy within and between populations. Population-scale pharmacogenomics helps to provide insights into the choice of optimal therapies and an opportunity to estimate, predict and minimize adverse events. Such an approach can potentially empower countries to formulate national selection and dosing policies for therapeutic agents thereby promoting public health with precision. We review the breadth and depth of worldwide population-scale sequencing efforts and its implications for the implementation of clinical pharmacogenetics toward making precision medicine a reality.

Pharmacogenetic and pharmacogenomic considerations of asthma treatment

INTRODUCTION

Pharmacogenetic and pharmacogenomic approaches are already utilized in some areas, such as oncology and cardiovascular disease, for selecting appropriate patients and/or establishing treatment and dosing guidelines. This is not true in asthma although many patients have different responses to drug treatment due to genetic factors. Areas covered: Several genetic factors that affect the pharmacotherapeutic responses to asthma medications, such as β₂-AR agonists, corticosteroids, and leukotriene modifiers and could contribute to significant between-person variability in response are described. Expert opinion: An expanding number of genetic loci have been associated with therapeutic responses to asthma drugs but the individual effect of one single-nucleotide polymorphism is partial. In fact, epigenetic changes can modify genetic effects in time-, environment-, and tissue-specific manners, genes interact together in networks, and nongenetic components such as environmental exposures, gender, nutrients, and lifestyle can significantly interact with genetics to determine the response to therapy. Therefore, well-designed randomized controlled trials or observational studies are now mandatory to define if response to asthma medications in individual patients can be improved by using pharmacogenetic predictors of treatment response. Meanwhile, routine implementation of pharmacogenetics and pharmacogenomics into clinical practice remains a futuristic, far-off challenge for many clinical practices.

Asthma management experiences of Australians who are native Arabic speakers

OBJECTIVE

The aim of this study was to explore the asthma management experiences of people with asthma within the Arabic-speaking community in Australia.

METHODS

Semi-structured interviews guided by a schedule of questions were conducted with 25 Arabic-speaking women with asthma\carer of a child with asthma, recruited from medical practices and community centers in Melbourne, Australia.

RESULTS

Twenty-five Arabic-speaking participants with asthma or caring for those with asthma were interviewed. Interviews lasted on average 25 minutes. Most participants or those they were caring for did not have well-controlled asthma. Thematic analyses of the interview transcripts highlighted five key emergent themes: stigma, health literacy, non-adherence, expectations, and coping styles. Findings indicated that many participants were not conversant about local information avenues or healthcare or facilities such as the Asthma Foundation or availability of Arabic translators during general practitioner (GP) consults. Many recent migrants were generally non-adherent with treatment; preferring to follow traditional folk medicine rather than consulting a GP or pharmacist. Some unrealistic expectations from doctors/treatment goals were expressed by a few participants. Some parents of children with asthma reported disappointment with the fact that their children did not grow out of asthma.

CONCLUSION

Low health literacy and in particular knowledge about asthma, cultural beliefs, language, and migration-related issues may all be affecting the level of asthma control in the Arabic-speaking population in Australia. Measures to enhance asthma and health system literacy designed to be culturally concordant with the beliefs, expectations, and experiences of such populations may be key to improving asthma management.

Role of muscarinic antagonists in asthma therapy

INTRODUCTION

Higher parasympathetic tone has been reported in asthmatics. In general, cholinergic contractile tone is increased by airway inflammation associated with asthma. Nevertheless, the role of muscarinic antagonists for the treatment of asthma has not yet been clearly defined. Areas covered: The use of SAMAs and LAMAs in asthma has been examined and discussed according with the published evidence. Particular attention has been given to the large Phase III clinical trial program designed to evaluate the efficacy and safety of tiotropium respimat added to standard treatment in adults, adolescents and children with persistent asthma across the spectrum of asthma severity. Expert commentary: The current evidence is that in patients with poorly controlled severe asthma despite the use of ICS and LABA, the addition of tiotropium significantly increases the time to the first severe exacerbation and provides a modest but sustained bronchodilation. Identical results should be produced using other LAMAs. In any case, the documentation that, at least in animal or in vitro models, LAMAs show significant anti-inflammatory and anti-proliferative capacities and are able to inhibit airway remodeling induced by allergens makes a strong presumption that the use of LAMAs in asthma may go beyond the simple bronchodilator effect.

Pharmacodynamic and pharmacokinetic assessment of fluticasone furoate + vilanterol for the treatment of asthma

INTRODUCTION

The pharmacokinetic (PK) and pharmacodynamic (PD) effects of long-acting β2-agonists and mostly inhaled corticosteroids (ICSs) shape the efficacy and safety of these agents in the treatment of asthma. In fact, the PK and PD characteristics of the drug largely determine the degree of pulmonary targeting Areas covered. In this review, we summarize the PK and PD properties of inhaled fluticasone furoate (FF) and vilanterol trifenatate (VI) and their fixed-dose combination (FDC) for the treatment of asthma Expert opinion. It is difficult to interpret the data that we have described because the preclinical and clinical development of FF/VI FDC was not really based on solid information on quantitative PK/PD approach. Unfortunately, for both FF and VI we only know concentrations in systemic blood, a compartment that is downstream of both target and non-target respiratory tissue. This lack of information does not allow us to understand the temporal relationship between the delivered dose and the drug concentration at the sites of action within the lungs. In addition, all studies performed with FF and VI did not address the fundamental issue that asthma can significantly alter lung deposition, absorption and also clearance of inhaled medicines.