Clinical effectiveness and safety of montelukast in asthma. What are the conclusions from clinical trials and meta-analyses?

β2-Adrenoreceptor Agonists, Montelukast, and Parkinson Disease Risk

OBJECTIVE

This study was undertaken to examine the association between montelukast use, β2-adrenoreceptor (β2AR) agonist use, and later Parkinson disease (PD).

METHODS

We ascertained use of β2AR agonists (430,885 individuals) and montelukast (23,315 individuals) from July 1, 2005 to June 30, 2007, and followed 5,186,886 PD-free individuals from July 1, 2007 to December 31, 2013 for incident PD diagnosis. We estimated hazard ratios and 95% confidence intervals using Cox regressions.

RESULTS

We observed 16,383 PD cases during on average 6.1 years of follow-up. Overall, use of β2AR agonists and montelukast were not related to PD incidence. A 38% lower PD incidence was noted among high-dose montelukast users when restricted to PD registered as the primary diagnosis.

INTERPRETATION

Overall, our data do not support inverse associations between β2AR agonists, montelukast, and PD. The prospect of lower PD incidence with high-dose montelukast exposure warrants further investigation, especially with adjustment for high-quality data on smoking. ANN NEUROL 2023;93:1023-1028.

Montelukast as a potential treatment for COVID-19

INTRODUCTION

Montelukast is a leukotriene inhibitor that is widely used to treat chronic asthma and allergic rhinitis. The drug interferes with molecular signaling pathways produced by leukotrienes in a variety of cells and tissues throughout the human body that lead to tightening of airway muscles, production of aberrant pulmonary fluid (airway edema), and in some cases, pulmonary inflammation.

AREAS COVERED

Montelukast has also been noted to have anti-inflammatory properties, suggesting it may have a role in the treatment of coronavirus disease 2019 (COVID-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has been noted to induce misfiring of the immune system in some patients. A literature search of PubMed was performed to identify all relevant studies of montelukast and SARS-CoV-2 through 27 January 2023.

EXPERT OPINION

Montelukast has been the subject of small studies of SARS-CoV-2 and will be included in a large, randomized, double-blind, placebo-controlled study of outpatients with COVID-19 sponsored by the United States National Institutes of Health known as Accelerating COVID-19 Therapeutic Interventions and Vaccines-6. This paper reviews what is known about montelukast, an inexpensive, well-tolerated, and widely available medication, and examines the rationale for using this drug to potentially treat patients with COVID-19.

Adverse Drug Reactions (ADRs) of Montelukast in Children

Montelukast is a leukotriene receptor antagonist (LTRA) commonly prescribed for asthma, allergic rhinitis and sleep-related breathing disorders. Recently, some studies have reported several adverse events, such as neuropsychiatric disorders and sleep disturbances, among children.

OBJECTIVE

To obtain more insight into the safety profile of montelukast for children with asthma, allergic rhinitis and sleep-related breathing disorders.

METHOD AND RESULTS

We retrospectively studied all adverse drug reactions to montelukast among 385 children 6 months or older in six tertiary centers over a two-year period. A total of 89.6% were asthmatic, 50% had allergic rhinitis and 13.6% had sleep-related breathing disorders; Singulair was the most common type of montelukast used (67.9%). This study reported a high prevalence of adverse drug reactions among 123 patients (31.9%), predominantly in those aged 4-9 years (52.8%), followed by adolescents (24.4%) and toddlers (22.8%). Two (ADRs) were reported in 9.8% of the children, while three or more were reported in 5.5%. Sleep disturbance was the most common (ADRs), affecting 15.1% of participants (overlap was common; 5.5% of children experienced sleep difficulties, 4.4% experienced sleep interruption and decreased sleep, and 1.82% experienced nightmares), followed by agitation (10.4%), pain (9.4%) and hyperactivity (6.8%). No serious (ADRs) were reported. Eleven percent of families faced difficulties in purchasing montelukast, and only 57% of families had insurance. Misconceptions were common (9.8% reported it to be a steroid, while 30.6% believed it to be a bronchodilator). Although 81% of the families believed it was an effective and preventive medication, 5.3% stopped the drug due to concern about side effects, especially agitation (3%) and nightmares (0.6%).

CONCLUSION

These data demonstrate that montelukast is effective, but the associated adverse neuropsychiatric drug reactions are more prevalent than those reported in the literature. In particular, sleep disturbance, agitation, pain and hyperactivity were observed. Pediatricians should be aware of such (ADRs). Misconceptions about montelukast are still common, and parental counseling and urgent epidemiological studies are needed to quantify the risk for management plans.

Increased Risk of Tourette Syndrome with Leukotriene Modifier Use in Children with Allergic Diseases and Asthma: A Nationwide Population-Based Study

(1) Background: Cysteinyl leukotriene receptor antagonists (LTRAs), including montelukast and zafirlukast, are FDA-approved for treating pediatric asthma and allergic diseases. Tourette syndrome (TS), a common neuropsychiatric disorder in children, is associated with allergic diseases and asthma. In this study, we investigated the risk of TS following an LTRA prescription for pediatric allergic diseases. (2) Methods: Children younger than 18 years of age who were newly diagnosed with asthma, allergic rhinitis, or atopic dermatitis between 1 January 2005 and 31 December 2018 and who were registered in the Taiwan National Health Insurance Research Database, which comprises the medical records of nearly 23 million Taiwanese population, were enrolled. LTRA users were matched with randomly selected LTRA non-users by sex, age, asthma-diagnosis year, and urbanization level. In total, 26,984 participants with allergic disease and TS were enrolled and included in the Cox proportional hazards model analysis. (3) Results: Children with allergic disease and asthma treated with LTRAs had a higher risk for TS than LTRA non-users (adjusted hazard ratio 1.376 [95% CI: 1.232−1.536], p < 0.001). LTRA users had a significantly higher risk for TS than LTRA non-users with allergic disease. The cumulative incidence of TS was significantly higher in LTRA users than in non-users with allergic diseases and asthma (log-rank test, p < 0.0001). (4) Conclusion: A prescription of LTRAs, mainly montelukast, increased the risk of TS among children with asthma, allergic rhinitis, or atopic dermatitis. The mechanism underlying the neuropsychiatric effect of LTRAs needs further investigation.

PGC-1α activity and mitochondrial dysfunction in preterm infants

Extremely low gestational age neonates (ELGANs) are born in a relatively hyperoxic environment with weak antioxidant defenses, placing them at high risk for mitochondrial dysfunction affecting multiple organ systems including the nervous, respiratory, ocular, and gastrointestinal systems. The brain and lungs are highly affected by mitochondrial dysfunction and dysregulation in the neonate, causing white matter injury (WMI) and bronchopulmonary dysplasia (BPD), respectively. Adequate mitochondrial function is important in providing sufficient energy for organ development as it relates to alveolarization and axonal myelination and decreasing oxidative stress via reactive oxygen species (ROS) and reactive nitrogen species (RNS) detoxification. Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) is a master regulator of mitochondrial biogenesis and function. Since mitochondrial dysfunction is at the root of WMI and BPD pathobiology, exploring therapies that can regulate PGC-1α activity may be beneficial. This review article describes several promising therapeutic agents that can mitigate mitochondrial dysfunction through direct and indirect activation and upregulation of the PGC-1α pathway. Metformin, resveratrol, omega 3 fatty acids, montelukast, L-citrulline, and adiponectin are promising candidates that require further pre-clinical and clinical studies to understand their efficacy in decreasing the burden of disease from WMI and BPD in preterm infants.

Prescription Patterns of Asthma Preventers Among Children and Adolescents Between Australia and South Korea

Purpose: Inhaled Corticosteroids (ICSs) and oral Leukotriene Receptor Antagonists (LTRAs) are commonly prescribed asthma preventers, however, concerns have been raised as to whether montelukast (LTRA) is associated with an increase in occurrences of neuropsychiatric side effects in children. Our study was conducted to observe prescribing patterns of asthma preventers among paediatric patients specifically focusing on ICSs and LTRAs between Australia and South Korea to see intercountry differences in the use of these medicines. Materials and Methods: The Health Insurance Review and Assessment Paediatric Patients Sample dataset for South Korea and data provided by Services Australia were used in the study. Paediatric patients aged between 3 and 19 with more than one dispensing of an asthma preventer and at least one reliever between 1 Jan 2018 and 31 December 2018 were selected. Prevalence per 1,00,000 persons and standardised prevalence were estimated. Results: A total of 3,58,470 patients (2,04,270 from South Korea and 1,54,200 from Australia) were included in the study. A higher prevalence of ICS-based inhalers was seen in Australia with 80.1% compared to 13.5% in South Korea. In addition, Australia showed a stronger tendency of prescribing high dose ICS-based inhalers compared to South Korea with 22.9% vs. 4.9%. In contrast, use of LTRAs was more prevalent in South Korea with 57.6% while in Australia, montelukast was the only LTRA dispensed at a proportion of 18.9%. Moreover, 29.9% of xanthines which are orally available preventers, were prescribed more frequently in South Korea compared to Australia (0.1%). Conclusion: Australia showed a tendency of prescribing ICS-based preventers whereas South Korea exhibited a preference towards the oral LTRAs. Given the potential risk of neuropsychiatric side effects among paediatric patients with montelukast, reasons for the high use of montelukast in South Korea should be investigated further.

Montelukast ameliorated pemetrexed-induced cytotoxicity in hepatocytes by mitigating endoplasmic reticulum (ER) stress and nucleotide oligomerization domain-like receptor protein 3 (NLRP3) activation

Pemetrexed (PEM) is an effective chemotherapeutic drug used for the treatment of clinical non-small-cell lung cancer (NSCLC) and is reported to induce severe hepatotoxicity. Exploring potential drugs which could counteract the side effects of PEM is of great clinical interest. Here, we aim to examine the beneficial effects of Montelukast, a novel anti-asthma drug, against PEM-induced cytotoxicity in hepatocytes, and to explore the underlying mechanism. We found that Montelukast reduces cytotoxicity of PEM in hepatocytes, confirmed by its increasing cell viability and reducing lactate dehydrogenase (LDH) release. In addition, Montelukast attenuated PEM-induced oxidative stress by reducing mitochondrial reactive oxygen species (ROS), increasing reduced glutathione (GSH), and downregulating NADPH oxidase 4 (NOX-4) expression. Importantly, Montelukast suppressed PEM-induced activation of the nucleotide oligomerization domain-like receptor protein 3 (NLRP3) inflammasome and mitigated endoplasmic reticulum (ER) stress by reducing NLRP3, growth arrest, and DNA damage-inducible protein 34 (GADD34), CEBP-homologous protein (CHOP), and also blocking the eukaryotic initiation factor 2 (eIF-2α)/activating transcription factor 4 (ATF4) signaling pathway. Lastly, we found that Montelukast inhibited the transcriptional activity of nuclear factor kappa-B (NF-κB). Montelukast exerted a protective action against PEM-induced cytotoxicity in hepatocytes by mitigating ER stress and NLRP3 activation.

Treatment of pediatric mild persistent asthma with low-dose budesonide inhalation suspension vs. montelukast in China

BACKGROUND

There are limited studies comparing budesonide inhalation suspension (BIS) with montelukast in real-world settings where treatment adherence and persistency may be suboptimal. This real-world study aims to investigate the control effectiveness of montelukast or BIS as a monotherapy in Chinese children with mild asthma.

METHODS

Data were derived from a retrospective questionnaire-based analysis of 2‒14-year-old children with mild persistent asthma, who received either 500 µg of BIS (n = 153) or 4‒5 mg of montelukast (n = 240) once daily. The indicators of asthma control, the Asthma Control Test (ACT)/Childhood ACT (C-ACT) score, and the asthma-related medical costs were assessed. The differences between the two groups were compared using an unpaired t-test (normally distributed), Mann-Whitney U test (non-normally distributed) or chi-squared test (categorical variables).

RESULTS

Medication compliance in the past 3-month period was better in the montelukast group than in the BIS group (P = 0.042). The montelukast group exhibited better asthma control in the past 4-week period, including lower percentages of asthmatic children with symptoms more than twice a week (P = 0.021), had night waking or night coughing (P = 0.022), or required reliever medication more than twice a week (P < 0.001). The montelukast group had a lower percentage of children with an ACT/C-ACT score ≤ 19 (P = 0.015). Caregivers reported a significantly better exercise tolerance in the children who received montelukast vs. BIS in the past 12 months (P < 0.001). Significantly higher medical expenditures attributable to asthma in the past 12 months were observed in the BIS group vs. montelukast group (P < 0.001).

CONCLUSION

Both treatments provided acceptable overall asthma control in children with mild persistent asthma; however, more reliever medication and more medical expenditures attributable to asthma were needed for BIS vs. montelukast in real-world settings, where factors such as compliance were also taken into account.

Anti-IgE Effect of Small-Molecule-Compound Arctigenin on Food Allergy in association with a Distinct Transcriptome Profile

BACKGROUND

Excessive production of IgE plays a major role in the pathology of food allergy. In an attempt to identify anti-IgE natural products, Arctium Lappa was one of the most effective herbs among approximately 300 screened medicinal herbs. However, little is known about its anti-IgE compounds.

OBJECTIVE

To identify compounds from Arctium Lappa for targeted therapy on IgE production and explore their underlying mechanisms.

METHODS

Liquid-liquid extraction and column chromatographic methods were used to purify the compounds. IgE inhibitory effects were determined on IgE producing human myeloma U266 cells, peanut-allergic murine model, and PBMCs from food-allergic patients. Genes involved in IgE inhibition in PBMCs were studied by RNA sequencing.

RESULTS

The main compounds isolated were identified as arctiin and arctigenin. Both compounds significantly inhibited IgE production in U266 cells, with arctigenin the most potent (IC50=5.09μg/mL). Arctigenin (at a dose of 13.3 mg/kg) markedly reduced peanut-specific IgE levels, blocked hypothermia and histamine release in a peanut-allergic mouse model. Arctigenin also significantly reduced IgE production and Th2 cytokines (IL5, IL13) by PBMCs. We found 479 differentially expressed genes in PBMCs with arctigenin treatment (p<0.001 and fold-change ≥1.5), involving 24 gene ontology terms (p<0.001, FDR <0.05); cell division was the most significant. Eleven genes including UBE2C and BCL6 were validated by qPCR.

CONCLUSION

Arctigenin markedly inhibited IgE production in U266 cells, peanut allergic murine model and PBMCs from allergic patients by down-regulating cell division, cell cycle-related genes and up-regulating anti-inflammatory factors.

Role of montelukast in multitrigger wheezers attending chest clinic in Punjab, India

BACKGROUND

Wheeze is seen in 40% of preschool children, one-third of these may develop recurrent wheeze. Montelukast is an oral, once a day, easy to give therapy but there is no definite evidence to support its use in a recent meta-analysis. Present study was done to evaluate role of daily montelukast and various factors affecting the outcome after therapy in multitrigger wheeze (MTW).

METHODS

A prospective study conducted in Pediatric chest clinic over 18 months at DMCH, Ludhiana. Children from 6 months to 5 years, diagnosed cases of MTW were started on montelukast. Diagnosis based on symptoms of recurrent wheeze triggered by various allergens/precipitants was made by pediatrician in charge of chest clinic. Children were followed up at 1 and 3 months. They were labeled as controlled, partially controlled, or uncontrolled as per global initiative for asthma guidelines. Data were used to compare the outcome related to various factors.

RESULTS

Total 139 out of 150 children came for regular follow-up. At the end of 3 months, 94 (67.7%) were controlled, 8 (5.7%) partially controlled, and 37 (26.6%) children remained uncontrolled on montelukast. Factors associated with poor control were onset of symptoms at younger age (<6 months of age), family history of allergies, prior multiple visits or hospitalizations due to MTW, use of MDI in the past. No significant side effects were reported by parents.

CONCLUSION

Symptomatically two-third of children became better after starting montelukast. There were few factors which resulted in poorer control in subset of patients.

The Role of Innate Immunity and Bioactive Lipid Mediators in COVID-19 and Influenza

In this review, we discuss spatiotemporal kinetics and inflammatory signatures of innate immune cells specifically found in response to SARS-CoV-2 compared to influenza virus infection. Importantly, we cover the current understanding on the mechanisms by which SARS-CoV-2 may fail to engage a coordinated type I response and instead may lead to exaggerated inflammation and death. This knowledge is central for the understanding of available data on specialized pro-resolving lipid mediators in severe SARS-CoV-2 infection pointing toward inhibited E-series resolvin synthesis in severe cases. By investigating a publicly available RNA-seq database of bronchoalveolar lavage cells from patients affected by COVID-19, we moreover offer insights into the regulation of key enzymes involved in lipid mediator synthesis, critically complementing the current knowledge about the mediator lipidome in severely affected patients. This review finally discusses different potential approaches to sustain the synthesis of 3-PUFA-derived pro-resolving lipid mediators, including resolvins and lipoxins, which may critically aid in the prevention of acute lung injury and death from COVID-19.

Pharmacokinetics and Bioequivalence Evaluation of Two Montelukast Sodium Chewable Tablets in Healthy Chinese Volunteers Under Fasted and Fed Conditions

Purpose

The aim of this study was to assess and compare the pharmacokinetic (PK) properties and bioequivalence of montelukast sodium chewable tablets prepared by two different manufacturers in healthy Chinese volunteers to obtain adequate PK evidence for the registration approval of the test formulation.

Patients and Methods

A randomized-sequence, single-dose, open-label, 2-period crossover study was conducted in fasted and fed healthy Chinese volunteers (Chinese Clinical Trials Registry identifier: CTR20182362). Eighteen subjects each were selected for a fasted study and a fed study. Eligible participants were randomly assigned in a 1:1 ratio to receive a single dose of the reference formulation or the test formulation, followed by a 5-day washout period and the administration of the alternate formulation. Plasma samples were collected over a 24-hour period following tablet administration and analyzed for montelukast contents by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The PK parameters, such as maximum serum concentration (C_max), area under the curve (AUC) from t = 0 to the last quantifiable concentration (AUC_0–t), AUC from t = 0 to infinity (AUC_0–∞), half-life (t_1⁄2), time to C_max (T_max), and terminal elimination rate constant (λ_z), were evaluated. The safety assessment included changes in vital signs (blood pressure, pulse, and temperature) or laboratory tests (hematology, blood biochemistry, hepatic function, and urinalysis) and the incidence of adverse events (AEs).

Results

The geometric mean ratios (GMRs) between the two formulations for the primary pharmacokinetic parameters (C_max, AUC_0–24, and AUC _0–∞) and the corresponding 90% confidence intervals (Cis) were all within the range of 80.00–125.00% for both the fasting and fed states. The safety profiles for both treatments were comparable.

Conclusion

The PK analysis revealed that the test and reference formulations of montelukast sodium chewable tablets were bioequivalent and well-tolerated by healthy Chinese subjects.

Management of Pediatric Chronic Spontaneous Urticaria: A Review of Current Evidence and Guidelines

Chronic urticaria (CU) is associated with debilitating symptoms such as pruritic wheals and/or angioedema, which can significantly affect patients’ sleep, productivity and quality of life. Chronic spontaneous urticaria (CSU) is defined in cases in which no triggering factor is identified. Various guidelines directing the optimal management of CU in the adult population were published and updated over the recent years with the most accepted and widely used being the EAACI/GA²LEN/EDF/WAO 2017 guidelines. Meanwhile, guidelines specific to the pediatric population are scarce, mainly due to the fact that high quality evidence is lacking for many treatment options in this age group. The objective of this article is to review and synthesize the existing literature regarding the management of pediatric CSU. Our review highlights evidence supporting the EAACI/GA²LEN/EDF/WAO 2017 treatment guidelines with non-sedating second-generation antihistamines (sgAHs) as the mainstay of treatment for pediatric CSU, considering their demonstrated efficacy and reassuring safety profile. Additionally, the use of omalizumab in adolescents is well supported by the current literature. There is limited data available regarding the updosing of sgAHs, omalizumab in children with CSU under 12 years of age and the treatment with cyclosporine and leukotriene receptor antagonists (LTRAs) in pediatric patients of all ages. However, the results from currently available case series and case reports are promising for omalizumab and cyclosporine use in children with CSU, although large and well-designed randomized control trials (RCTs) assessing these treatment options are needed in order to formulate strong recommendations for their use. First-generation antihistamines (fgAHs) remain commonly used in pediatric CSU treatment despite a lack of studies assessing their efficacy and safety in the pediatric population and their widely known inferior safety profile compared to sgAHs.

Neuropsychiatric adverse drug reactions induced by montelukast impair the quality of life in children with asthma

INTRODUCTION

Montelukast-induced neuropsychiatric adverse drug reactions (ADRs) have been reported in retrospective studies. This study aimed to reveal the neuropsychiatric ADRs triggered in patients taking montelukast due to asthma in real time, and to evaluate the effect of these ADRs on quality of life (QoL).

METHODS

Patients, ages 3-18 years, taking montelukast for the first time and their parents were included. Ages 3-7 years were defined as the preschool and ages 8-18 years as the school-age group. At the beginning of the study and at the end of the second week of treatment, the neuropsychiatric complaint assessment questionnaire and the KINDL QoL scale were administered to patients and their parents. The effect of ADRs on the decrease in QoL was evaluated by multivariable logistic regression.

RESULTS

Neuropsychiatric ADRs were reported in 78 (62.4%) of 125 patients, who recovered when the drug was discontinued. Temperamental behavior, nightmares and sleep disorders occurred significantly more often in both groups compared with pretreatment (p < 0.001 for each). In both groups, except in the child-reported family relationships subscale in the school-age group, significant decreases were found in both child and parent proxy-reported QoL total/sub-scores compared with pretreatment (p˂0.001 for each). It was found in the evaluation that the overall QoL of those experiencing ADRs in both age groups was more affected. (Child-reported QoL OR_{preschool age}=2.66, p = 0.048; OR_school-age=5.95, p = 0.027; parent-proxy QoL OR_{preschool age} =3.52, p = 0.010, OR_school-age=6.43, p = 0.027).

CONCLUSIONS

Montelukast-induced neuropsychiatric ADRs are more frequent than reported in the literature and negatively impact children's QoL.

Dysregulated metabolism of polyunsaturated fatty acids in eosinophilic allergic diseases

Polyunsaturated fatty acids (PUFAs), represented by the omega-6 fatty acid arachidonic acid (AA) and omega-3 fatty acid docosahexaenoic acid (DHA), are essential components of the human body. PUFAs are converted enzymatically into bioactive lipid mediators, including AA-derived cysteinyl leukotrienes (cys-LTs) and lipoxins and DHA-derived protectins, which orchestrate a wide range of immunological responses. For instance, eosinophils possess the biosynthetic capacity of various lipid mediators through multiple enzymes, including 5-lipoxygenase and 15-lipoxygenase, and play central roles in the regulation of allergic diseases. Dysregulated metabolism of PUFAs is reported, especially in severe asthma, aspirin-exacerbated respiratory disease, and eosinophilic chronic rhinosinusitis (ECRS), which is characterized by the overproduction of cys-LTs and impaired synthesis of pro-resolving mediators. Recently, by performing a multi-omics analysis (lipidomics, proteomics, and transcriptomics), we demonstrated the metabolic derangement of eosinophils in inflamed tissues of patients with ECRS. This abnormality occurred subsequent to altered enzyme expression of gamma-glutamyl transferase-5. In this review, we summarize the previous findings of dysregulated PUFA metabolism in allergic diseases, and discuss future prospective therapeutic strategies for correcting this imbalance.

Effect of Montelukast on the Symptom Severity Score of Allergic Rhinitis

Introduction Rhinitis is a common respiratory disorder that can be broadly defined as an inflammation of nasal mucosa. Allergic rhinitis is the most common form of chronic rhinitis characterized by one or more symptoms including sneezing, nasal itching, nasal congestion, postnasal drip, and rhinorrhea. Montelukast is an antagonist to the leukotriene receptor. It is non-sedating, dosed once daily, and has a safety profile similar in adults and children, with approval down to six months of age. The purpose of the study was to see the improvement in the severity of symptoms of the patients with allergic rhinitis treated with montelukast. Methods The symptom severity score for allergic rhinitis was calculated by asking the patient to evaluate the severity of individual symptoms (sneezing, nasal congestion, rhinorrhea, and postnasal drip) against the 4-point scoring scale over the last 24 hours. After explaining the scoring system to the patient, a proforma was filled before starting the treatment. A dose of 10 mg of montelukast once daily was prescribed. On the follow-up visit after four weeks of therapy, compliance was ensured and then the symptom severity score was recorded again on the proforma. The total nasal symptom severity score (TNSSS) was calculated as a sum of all four nasal symptoms. Pre- and post-treatment mean of TNSSS was compared using a t-test. P-value of less than 0.05 was considered significant. Results A total of 140 patients were included in the study. The mean age was 30 years. The minimum age was 15 years and the maximum age was 45 years. There were 93 males and 47 females. The difference between pre- and post-mean values of TNSSS was 5.82. Both pre- and post-mean of TNSSS were compared using the t-test, and P-value was significant, i.e., <0.005. Conclusions The common symptoms of allergic rhinitis evaluated in the study showed improvement in response to the treatment with montelukast. The improvement in symptom severity score was maximum in sneezing and least in rhinorrhea. In light of recent developments on neuropsychiatric adverse effects and FDA warnings, caution needs to be exercised to reserve the use of montelukast for the selected patients.

Mechanisms underlying the protective effect of leukotriene receptor antagonist montelukast against doxorubicin induced testicular injury in rats

The obligatory use of cytotoxic drugs to face the malignant tumors results in survivors that suffer from long term health problems. Fertility problems, especially in young boys, exert one of the major consequences of chemotherapy treatment that needs resolution. We investigate the potential effect of the cysteinyl leukotriene receptor antagonist montelukast on doxorubicin-induced testicular damage. Five groups of adult Wistar male rats were subjected to the following treatment; vehicle for the control group, montelukast (20 mg/kg orally daily for 10 days) for the drug control, doxorubicin (12 mg/kg intraperitoneal injection once at 5th day) for the toxic group, montelukast at 10 mg/kg + doxorubicin, montelukast at 20 mg/kg + doxorubicin. The period of the experiment was 10 days administration of montelukast, while doxorubicin was injected at the 5th day. Results of serum testosterone, testicular lipid peroxidation, antioxidant status, and histopathology revealed protection of montelukast against doxorubicin-induced testicular damage. The pro-apoptotic caspase 3 and the pro-inflammatory tumor necrosis factor-alpha were examined immunohistochemically and showed a significant decrease with montelukast treatment as compared to doxorubicin group. Doxorubicin increased gene expression of matrix metalloproteinase 9 and decreased peroxisome proliferator activated receptor gamma. Montelukast treatment restored their expressions to normal values. In conclusion, montelukast administration can ameliorate the testicular damage induced by doxorubicin based on its anti-inflammatory, antioxidant and anti-apoptotic effects as well as by of modulation of important genes expression.

Cysteinyl leukotriene metabolism of human eosinophils in allergic disease

Eosinophils are multifaceted immune cells with diverse functions that enhance allergic inflammation. Cysteinyl leukotrienes (cys-LTs), mainly synthesized in eosinophils, are a class of inflammatory lipid mediators produced via multiple enzymatic reactions from arachidonic acid. Multiple clinical studies have reported dysregulated fatty acid metabolism in severe asthma and aspirin-exacerbated respiratory diseases. Therefore, understanding the mechanism responsible for this metabolic abnormality has attracted a lot of attention. In eosinophils, various stimuli (including cytokines, chemokines, and pathogen-derived factors) prime and/or induce leukotriene generation and secretion. Cell-cell interactions with component cells (endothelial cells, epithelial cells, fibroblasts) also enhance this machinery to augment allergic responses. Nasal polyp-derived eosinophils from patients with eosinophilic rhinosinusitis present a characteristic fatty acid metabolism with selectively higher production of leukotriene D₄. Interestingly, type 2 cytokines and microbiome components might be responsible for this metabolic change with altered enzyme expression. Here, we review the regulation of fatty acid metabolism, especially cys-LT metabolism, in human eosinophils toward allergic inflammatory status.

Erythromycin Releasing PVA/sucrose and PVA/honey Hydrogels as Wound Dressings with Antibacterial Activity and Enhanced Bio-adhesion

The present study deals with preparation and characterization of thermally crosslinked PVA-based hydrogels containing honey and sucrose for the purpose of erythromycin delivery. The hydrogels have been characterized and compared by scanning electron microscopy, Fourier transform infrared spectroscopy, and bio-adhesion tests. Swelling measurements showed that addition of sucrose and honey decreased the equilibrium swelling of the hydrogels. Results of release studies showed that the amount of erythromycin, released at the early hours was higher for PVA/sucrose and PVA/honey hydrogels compared to PVA hydrogel while the drug released at later times was highly reduced for PVA/honey hydrogel. Both Peppas-Sahlin and Korsmeyer-Peppas models fitted well to the release data. Fitting Peppas-Sahlin model to the release data showed that at the initial times, release of drug from the hydrogel network was mainly governed by Fickian mechanism; however, at later times the drug is dominantly released by relaxational mechanism due to swelling of the network,. Addition of honey improved the bio-adhesion of PVA/honey hydrogel as compared to PVA/sucrose and pure PVA hydrogel. Results of antibacterial tests showed growth inhibitory action of erythromycin-loaded PVA hydrogels against Pseudomonas aeruginosa and Staphylococcus aureus bacteria. This study indicates that these hybrid hydrogels are capable of being used as functional wound dressings aiming to control the rate of antibiotic delivery to the wound site and prevent the wounds from infection.

CB2 Agonist (AM1241) Improving Effect on Ovalbumin-Induced Asthma in Rats

Asthma is a disease characterized by spontaneous contraction of the airways in response to a wide variety of endogenous and exogenous stimuli. Many asthma models are used to mimic the human asthma model in the literature. In order to better understand the role of the cannabinoid (CB) 2 receptor in the ovalbumin (OVA)-induced asthma model, a combination of both selective CB2 agonist (AM1241) and antagonist (AM630) was used to improve inflammatory hypersensitivity and edema in rats. In the present study, it was found that OVA decreased body weight (p < 0.05), increased lung weights (p < 0.05), increased diastolic and systolic blood pressure (p < 0.001), and caused irregularity in pulmonary functions (p < 0.001). Moreover, CB2 agonist was found not to reduce body weight, cause blood pressure and respiratory irregularities (p < 0.05). OVA led to increase in IgE, TNF-α, IL-4, MDA level (p < 0.001), and total WBC count (p < .05). CB2 treatment caused to reduce the number of total WBC and the level of total protein in BALF, to hinder to increase level of MDA, IgE, TNF-α, and IL-4 (p < 0.05) in BALF or serum or lung tissue. But CB2-antagonist treatment prevented the protective effect of CB2 agonist. The aim of this study was to study the role of the CB2 receptor in the OVA induced asthma model, to improve inflammatory hypersensitivity, and edema in the rats. The results suggested that CB2 agonist administration to OVA induced asthmatic rats via anti-asthmatic potential through inhibition of parameters such as IgE, IL-4, TNF-α, microvascular escape, and oxidative stress.

Asthma pharmacotherapy: an update on leukotriene treatments

Introduction: Asthma is a chronic inflammatory disease of the airways with a large heterogeneity of clinical phenotypes. There has been increasing interest regarding the role of cysteinyl leukotriene (LT) and leukotriene receptor antagonists (LTRA) in asthma treatment.Areas covered: This review summarized the data (published in PubMed during 1984-2019) regarding LTRA treatment in asthma and LTs-related airway inflammation mechanisms. Involvement of LTs C₄/D₄/E₄ has been demonstrated in the several aspects of airway inflammation and remodeling. Novel pathways related to LTE₄, the most potent mediator, and its respective receptors have recently been studied. Antagonists against cysteinyl leukotriene receptor (CysLTR) type 1, including montelukast, pranlukast and zafirlukast, have been widely prescribed in clinical practices; however, some clinical trials have shown insignificant responses to LTRAs in adult asthmatics, while some phenotypes of adult asthma showed more favorable responses to LTRAs including aspirin-exacerbated respiratory disease, elderly asthma, asthma associated with smoking, obesity and allergic rhinitis.Expert opinion: Further investigations are needed to understand the role of LTs in airway inflammation and remodeling of the asthmatic airways. There is a lack of biomarkers to predict responsiveness to LTRA, especially in adult asthmatics. Besides CysLTR1 antagonists, targets aiming other LT pathways should be considered.

Prevalence of Montelukast Use as an Add-On Therapy among Iraqi Asthmatics on Treatment Attending Al-Kindy Teaching Hospital and Al-Zahraa Center of Asthma and Allergy

BACKGROUND:

Montelukast (Singulair) is a cysteinyl leukotriene receptor antagonist, used for the maintenance treatment of asthma and to relieve symptoms of seasonal allergic rhinitis and asthma, also used for exercise-induced bronchospasm.

AIM:

This study was performed to determine the prevalence of Montelukast use as an add-on therapy among Iraqi asthmatic patients on treatment. Comparing the effectiveness of regimens with and without montelukast.

METHODS:

This descriptive cross-sectional study was carried out on 73 Iraqi asthmatic patients on treatment of both sexes with age range (18-60) years old, attending Al-Kindy Teaching Hospital and Al-Zahraa Centre of Asthma and Allergy, Baghdad, for the period between February and March 2017. A questionnaire was specifically prepared to meet the objectives and was used to collect the data of the study.

RESULTS:

There was a significant statistical reduction of frequency in asthmatic attacks after Montelukast treatment (p-value < 0.05). Out of 73 patients, 39 were males, and 34 were females, 46 were jobless, 37 were married, 63 were urban residents, 63 were educated. Prevalence of exacerbation factors was as following: infection was found in 60.3% of the patients, exercise in 57.5%, dust in 72.6%, smoking in 60.6%, food in 24.7%, others (stress, perfumes) in 20.5%. The prevalence of Montelukast use in this study was 46% (34 patients). Out of 34 patients using Montelukast, 28 were using inhaled salbutamol, 5 were using oral salbutamol, 15 were using inhaled corticosteroids, 9 were using systematic corticosteroids, 2 were using xanthines, and 6 were using ketotifen.

CONCLUSION:

Montelukast was used as add-on therapy with the inhaled corticosteroids to reduce the required dose of inhaled corticosteroids also the use of Montelukast lead to reduced number of exacerbations which will be reflected on the use of inhaled salbutamol and systematic corticosteroids. Also, Montelukast was superior to xanthines and ketotifen as an add-on therapy.

Role of Montelukast in Improving Quality of Life in Patients with Persistent Asthma

Introduction

Maintenance therapy of asthma has a crucial role in keeping the disease dormant and preventing frequent acute exacerbations. Asthma control may be achieved by inhaled corticosteroids (ICS) and/or long-acting beta-agonists (LABA). Leukotriene receptor antagonist - montelukast - may be added as an add-on to ICS/LABA or may also be given in monotherapy. The aim of this study was to evaluate the role of montelukast monotherapy as asthma control and its impact on the quality of life of these patients.

Methods

In this prospective, open-label, interventional study, montelukast 10 mg once daily was given to patients with mild to moderate persistent asthma for four weeks. Quality of life (QOL) was assessed on the Asthma Quality of Life Questionnaire - Standard (AQLQ-S) questionnaire. Asthma control was assessed on the Asthma Control Test (ACT). Data was entered and analyzed using SPSS version 23.0.

Results

On AQLQ-S, overall QOL improved with one month of montelukast therapy significantly. On sub-scales, except for emotional function, all other three sub-scales including symptoms, activity limitation, and environmental function improved significantly. Asthma control score also significantly improved with one month of montelukast therapy.

Conclusion

Montelukast has an effective role in asthma control and improvement of QOL in patients with mild to moderate persistent asthma.

Tiotropium add-on therapy is safe and reduces seasonal worsening in paediatric asthma patients

There remains an unmet need for effective, well-tolerated therapeutic options in paediatric patients with not fully controlled asthma, for whom safety is of paramount importance.Data were pooled from five randomised, double-blind, placebo-controlled studies evaluating tiotropium 5 or 2.5 µg versus placebo add-on therapy in patients with symptomatic asthma aged 1-17 years. Analysis included adverse events (AEs) and serious AEs (SAEs) reported throughout and for 30 days following treatment.Of 1691 patients treated, 1119 received tiotropium. Reporting of AEs was low and comparable across all groups: tiotropium 5 µg (51%), tiotropium 2.5 µg (51%) and placebo (54%). Reporting of drug-related AEs, those leading to discontinuation and SAEs was also low and balanced between treatment groups, irrespective of age, disease severity or sex. The number of AEs related to asthma symptoms and exacerbations was lower with tiotropium (5 µg) than with placebo, particularly during the seasonal peaks of these AEs.This comprehensive analysis of a large safety database allowed subgroup analyses that are often impractical with individual trials and provides further support for the safety of once-daily tiotropium Respimat add-on therapy in paediatric patients with symptomatic asthma.

Methodology for determining the correlation of the clinical efficacy of therapy with the addition of a drug (for example, anti-asthma therapy in children)

Introduction: In the recent years, much attention has been paid to the use of leukotriene receptor antagonists (LTRA) in the treatment of bronchial asthma (BA). It has been even proposed to use them as alternatives to hormone therapy. Yet, there are studies demonstrating the advantage of montelukast as similar to placebo. The objective was to create a methodology for determining the correlation of the clinical efficacy of therapy with the addition of a drug (on example, clinical efficacy of montelukast in an anti-asthmatic therapy in pediatric patients).

Materials and methods: The data on prescribed regimens was retrospectively extracted from the inpatient records of 608 BA patients admitted to hospital in 2014–2015. Mathematical evaluation was based on the risk factor concept.

Results and discussion: The absolute efficacies (AEs) was estimated to be 91.85% (95% CI 90.15–93.55%) in the exposed group; the attributable efficacy (AtE) was found to be 17.00% (95% CI 10.91–23.09%); the relative efficacy (RE) was found to be 1.23 (95% CI 0.21–2.24); and the population attributable efficacy (PAtE) was found to be 7.55% (95% CI 2.49–12.61%).

Conclusions: The AtE, RE, and PAtE were statistically significant. The RE was found to be 1.23. However, the lower limit of its 95% CI (0.21–2.24) was less than 1, indicating that the increase in clinical efficacy was not found to be statistically significant. In the studied sample positive outcome rates were 91.85% (95% CI 90.15–93.55%) in the exposed group and 74.85% (95% CI 72.49–77.21%) in the comparator group. He presented methodology for determining the correlation of the clinical efficacy of the pharmacotherapy regimen with the addition of a drug can be successfully applied in the future.

Effect of Montelukast 10 mg in Elderly Patients with Mild and Moderate Asthma Compared with Young Adults. Results of a Cohort Study

Background

The clinical characteristics and physio-pathogenic mechanisms of asthma in patients older than 60 years appear to differ from the behavior described for other age groups. Therefore, the effectiveness of medications for elderly patients with asthma should not be extrapolated from studies conducted on teenagers or young adults.

Objective

The study aimed to establish the clinical effect of montelukast 10 mg in elderly patients with mild and moderate asthma compared to its effect on young adults.

Method

A prospective cohort study was conducted during 12 weeks of follow-up, which consecutively included the total population of adult patients attended by a group of 21 general practitioners, between July and December 2016. Young adults (18-59 years) and older adults were included (60 years or older) with mild or moderate asthma, which, according to the criteria of his treating physician, had been prescribed montelukast 10 mg/day. The variables of interest were: use of inhaled corticosteroids during the last month, use of inhaled beta-2 adrenergic agonists as a rescue in the last month, having attended the emergency service during the last month due to an asthma attack, presence of wheezing in the physical examination, the number of attacks in the last month and the number of days without symptoms in the last month.

Results

A total of 126 patients entered the cohort and 104 completed the follow-up, of which 29% were older adults. On admission, 65.4% of patients (68/104) had used rescue inhaled beta2 in the last month and had been using schemes with corticosteroids. After 12 weeks of follow-up, 58.1% (43/74) of the young adults required treatment schedules with corticosteroids, while in the elderly, only 36.7% of the patients (11/30) required this treatment scheme (p-value: 0.047). Regarding the use of rescue inhaled beta-2 at 12 weeks, 55% of young adults reported using them, compared to 33.3% of older adults (p-value: 0.041).

Conclusion

In this cohort of patients, treated with montelukast 10 mg/day for 12 weeks, there was a reduction of broncho-obstructive symptoms and exacerbations of the disease. In older adults compared to young adults, a greater reduction in the use of beta2 agonists rescue medications and in the concomitant use of inhaled corticosteroid schemes was documented.

Determinants for asthma control, quality of life and use of complementary and alternative medicine in asthmatic pediatric patients in four cities

BACKGROUND

Asthma is a significant chronic health problem worldwide. Management aims at disease control by reducing functional impairment and exacerbations and improving quality of life (QoL). We report a multi-center study to survey asthma control and QoL in four cities in the Pearl River Delta.

METHODS

The conjoint survey involved ten Hong Kong pediatric hospitals/units, two Shenzhen hospitals, two Macau hospitals, and two Guangzhou hospitals on asthma control (using Asthma Control Test) and QoL (Pediatric Allergic Disease Quality of Life Questionnaire, PADQLQ). Acceptability of a treatment is graded as very good/good/fair/poor.

RESULTS

Good asthma control was only reported in 80% subjects in Hong Kong, but higher in sister cities (85-94%, P < 0.001). Allergic rhinitis, "incense burning", and "smoker in family" were prevalent among the four cities. Logistic regression showed better control of asthma was associated with better PADQLQ (B = - 0.029, P < 0.001), better acceptability of bronchodilator (B = - 1.488, P = 0.025), negatively with "smoker in family" (B = - 0.83, P = 0.015) and various PADQLQ domains. Conversely, worse PADQLQ was associated with allergic rhinitis severity (B = 4.77, P < 0.001), poor control of asthma (B = 7.56, P < 0.001), increased frequency of traditional Chinese medicine use (B = 1.7, P < 0.05), increased frequency of bronchodilator usage (B = 1.05, P < 0.05), "smoker in family" (B = 4.05, P < 0.05), and incense burning at home (B = 3.9, P < 0.05).

CONCLUSIONS

There are some clinical and cultural differences among the four southern Chinese cities within the Guangdong province. This study identifies potentially modifiable environmental and treatment factors associated with poor asthma control and QoL for health-care interventions. Having a smoker in the family is independently associated with poor asthma control and QoL.

Relationship Between Gender and the Effectiveness of Montelukast: An Italian/Danish Register-Based Retrospective Cohort Study

Rationale: Gender-related differences in asthma prevalence, pathophysiology and clinical features induced by sex steroids have been investigated, however, how gender influences response to asthma treatments in routine clinical practice have not yet been elucidated fully. This aspect is crucial for montelukast considering the jeopardization of asthmatic patients that benefit from this treatment and the existence of evidence of gender differences in leukotriene levels. Therefore, to fulfill this medical need, we investigated the role of gender on a set of montelukast' effectiveness surrogates in adults and pediatric patients with asthma. Methods: The study settings were Napoli 2 Local Health Unit (southern Italy) and the entire Danish territory. The study population was composed of adult and pediatric patients with asthma. Cumulative incidence curves, unadjusted and adjusted Cox regression were used as statistical models to compare aforementioned outcomes between genders. Results: Adult Italian male users of montelukast had a statistically lower persistence in montelukast treatment compared to female users. In the adjusted analyses, they had a higher hazard of montelukast' withdrawal (Hazard Ratio [HR] 1.07; 95% Confidence Interval [CI] 1.01-1.14), add-on/switch to a long-term treatment for asthma following montelukast withdrawal (HR 1.72; 95%CI 1.39-2.12), and rescue therapy with short-acting β2 agonist (HR 1.24; 95%CI 1.04-1.47). In the adult Danish cohort, we also found that male users had higher a hazard of rescue therapy with oral corticosteroids (HR 1.10; 95%CI 1.04-1.16). In the pediatric cohorts, no statistically significant differences were observed between genders for aforementioned outcomes. Conclusions: In adults, male gender was associated with increased hazards of montelukast discontinuation, add-on/switch to a long-term treatment for asthma following montelukast withdrawal, and rescue therapy with oral corticosteroids or short-acting β2 agonist when compared to the female gender. As expected, these associations were reversed or absent in pediatric patients.

Adverse drug reactions of montelukast in children and adults

Montelukast, a selective leukotriene receptor antagonist, is recommended in guidelines for the treatment of asthma in both children and adults. However, its effectiveness is debated, and recent studies have reported several adverse events such as neuropsychiatric disorders and allergic granulomatous angiitis. This study aims to obtain more insight into the safety profile of montelukast and to provide prescribing physicians with an overview of relevant adverse drug reactions in both children and adults. We retrospectively studied all adverse drug reactions on montelukast in children and adults reported to the Netherlands Pharmacovigilance Center Lareb and the WHO Global database, VigiBase^® until 2016. Depression was reported most frequently in the whole population to the global database VigiBase^® (reporting odds ratio (ROR) 6.93; 95% CI: 6.5–7.4). In the VigiBase^®, aggression was reported the most in children (ROR, 29.77; 95% CI: 27.5–32.2). Headaches were reported the most frequently to the Dutch database (ROR, 2.26; 95% CI: 1.61–3.19). Furthermore, nightmares are often reported for both children and adults to the Dutch and the global database. Eight patients with allergic granulomatous angiitis were reported to the Dutch database and 563 patients in the VigiBase^®. These data demonstrate that montelukast is associated with neuropsychiatric adverse drug reactions such as depression and aggression. Especially in children nightmares are reported frequently. Allergic granulomatous angiitis is also reported, a causal relationship has not been established.

Comprehensive Pharmacogenomic Study Reveals an Important Role of UGT1A3 in Montelukast Pharmacokinetics

To identify the genetic basis of interindividual variability in montelukast exposure, we determined its pharmacokinetics and sequenced 379 pharmacokinetic genes in 191 healthy volunteers. An intronic single nucleotide variation (SNV), strongly linked with UGT1A3*2, associated with reduced area under the plasma concentration–time curve (AUC_0‐∞) of montelukast (by 18% per copy of the minor allele; P = 1.83 × 10⁻¹⁰). UGT1A3*2 was associated with increased AUC_0‐∞ of montelukast acyl‐glucuronide M1 and decreased AUC_0‐∞ of hydroxymetabolites M5R, M5S, and M6 (P < 10⁻⁹). Furthermore, SNVs in SLCO1B1 and ABCC9 were associated with the AUC_0‐∞ of M1 and M5R, respectively. In addition, a candidate gene analysis suggested that CYP2C8 and ABCC9 SNVs also affect the AUC_0‐∞ of montelukast. The found UGT1A3 and ABCC9 variants associated with increased expression of the respective genes in human liver samples. Montelukast and its hydroxymetabolites were glucuronidated by UGT1A3 in vitro. These results indicate that UGT1A3 plays an important role in montelukast pharmacokinetics, especially in UGT1A3*2 carriers.

Steroid phobia, Chinese medicine and asthma control

BACKGROUND

Inhaled corticosteroids (ICS) are the mainstay of treatment for asthma. Corticosteroid (CS) phobia and fears are prevalent, and these may influence therapeutic efficacy and asthma control.

AIM

The aim of this study was to evaluate if CS fear is associated with asthma control in children.

METHODS

Patients aged >4 years with asthma at a pediatric outpatient clinic were surveyed, and the Asthma Control Test (ACT) was used for the assessment of asthma control.

RESULTS

Ninety-eight patients and their parents were interviewed. Thirty-four (35%) parents reported moderate or significant CS fear. They were more likely than those with no or little fear to have poorer asthma control (mean ACT scores 21.3 ± 4.0 vs 23.1 ± 3.3, P = 0.02), discuss their fears with their doctors (P < 0.001), request CS sparing medications (P = 0.044) and resort to Chinese medicine (CM) usage (P < 0.001). Backward binomial logistic regression showed parents with moderate/significant fears were more likely to discuss their fears with their doctors (OR: 5.21; 95% CI: 1.86-14.59; P = 0.002) and have used CM (OR: 4.28; 95% CI: 1.61-11.41; P = 0.004). CS fear was not translated to reduced self-reported compliance in the prescribed ICS. About 40% of the respondents had ever used Chinese Medicine (CM) with 82% of the users reported having used Chinese herbal medicine and 49% had used cold moxibustion.

CONCLUSIONS

CS fear and CM usage are prevalent. Parents with CS fear were more likely to have children with poorer asthma control and have used Chinese medicine. Physicians caring for children with asthma should be aware of parents with CS fear, prepared to address the fear or concerns and offer evidence-based alternative treatment.

Overexpression of ATP5b promotes cell proliferation in asthma

Asthma is a complicated systemic disease of the airways, which is characterized by variable symptoms, including bronchial hyper‑responsive-ness, inflammation and airflow obstruction. The prevalence of asthma has increased 2‑3‑fold over recent decades in developed countries; however, the molecular mechanism of asthma remains unclear. In the current study, the expression of recombinant protein Dermatophagoides farinaeI (Derf I) was induced by isopropyl β‑D‑1‑thiogalactoside (IPTG) and purified using Ni‑NTA. Derf I, an important antigen of asthma, was used to establish the animal model of asthma. Airway hyper‑responsiveness was mea-sured using unrestrained whole‑body plethysmography with a four‑chamber system. Immunoglobulin (Ig)E, IgG and IgG2a were analyzed using indirect enzyme‑linked immunosorbent assay (ELISA). Proteomic technology was applied to detect the difference between the normal lung tissue and asthma lung tissue samples of the asthma model. Cytokines in bronchoalveolar lavage fluid and the splenocyte culture medium were measured by ELISA and reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect the mRNA expression of ATP synthase, H+ transporting, mitochondrial F1 complex, β polypeptide (ATP5b). In addition, cell growth of arterial smooth muscle cells (ASMCs) was evaluated by MTT assay. In the current study, Derf I was successfully used to construct the animal model of asthma. Out of 23 proteins that exhibit 3‑fold upregulation or downregulation, ATP5b was chosen for further investigation. The data indicated that ATP5b was overexpressed in the asthma lung tissue when compared with the normal lung tissue. However, when ATP5b was knocked down, cell growth decreased. Therefore, overexpressed ATP5b leads to airway smooth muscle cell (ASMC) proliferation and finally to ASM thickening. Thus, to the best of our knowledge, this is the first study to report that the expression level of ATP5b was markedly increased in lung tissue samples of an asthma model compared with the tissue samples from normal lungs, which promoted ASMC proliferation and contributed to airway remodeling.

Neuropsychiatric adverse drug reactions in children initiated on montelukast in real-life practice

Although montelukast is generally well tolerated, postmarketing studies have reported serious neuropsychiatric adverse drug reactions (ADRs) leading to a United States Food and Drug Administration black box warning. The objective of this study was to determine the incidence of neuropsychiatric ADRs leading to discontinuation of montelukast in asthmatic children.We conducted a retrospective cohort study in children aged 1-17 years initiated on montelukast. In a nested cohort study, children initiated on montelukast as monotherapy or adjunct therapy to inhaled corticosteroids (ICS) were matched to those initiated on ICS monotherapy. A non-leading parental interview served to ascertain the occurrence of any ADRs with any asthma medication, and circumstances related to, and evolution of, the event.Out of the 106 participants who initiated montelukast, most were male (58%), Caucasian (62%) with a median (interquartile range) age of 5 (3-8) years. The incidence (95% CI) of drug cessation due to neuropsychiatric ADRs was 16 (10-26)%, mostly occurring within 2 weeks. Most frequent ADRs were irritability, aggressiveness and sleep disturbances. The relative risk of neuropsychiatric ADRs associated with montelukast versus ICS was 12 (2-90).In the real-life setting, asthmatic children initiated on montelukast experienced a notable risk of neuropsychiatric ADRs leading to drug cessation, that is significantly higher than that associated with ICS.

A meta-analysis of montelukast for recurrent wheeze in preschool children

There is conflicting evidence of the effectiveness of montelukast in preschool wheeze. A recent Cochrane review focused on its use in viral-induced wheeze; however, such subgroups are unlikely to exist in real life and change with time, recently highlighted in an international consensus report. We have therefore sought to investigate the effectiveness of montelukast in all children with preschool wheeze (viral-induced and multiple-trigger wheeze). The PubMed, Cochrane Library, Ovid Medline and Ovid EMBASE were screened for randomised controlled trials (RCTs), examining the efficacy of montelukast compared with placebo in children with the recurrent preschool wheeze. The primary endpoint examined was frequency of wheezing episodes. Five trials containing 3960 patients with a preschool wheezing disorder were analysed. Meta-analyses of studies of intermittent montelukast showed no benefit in preventing episodes of wheeze (mean difference (MD) 0.07, 95% confidence interval (CI) -0.14 to 0.29; mean for montelukast 2.68 vs placebo 2.54 (p = 0.5)), reducing unscheduled medical attendances (MD -0.13, 95% CI -0.33 to 0.07; mean for montelukast 1.62 vs placebo 1.78 (p = 0.21)) and reducing oral corticosteroids (MD -0.06, 95% CI -0.16 to 0.02; mean for montelukast 0.35 vs placebo 0.36 (p = 0.25)). The pooled results of the continuous regimen showed no significant difference in the number of wheezing episodes between the montelukast and placebo groups (MD -0.40, 95% CI -1.00 to 0.19; mean for montelukast 2.05 vs placebo 2.37 (p = 0.18)).

CONCLUSIONS

This review highlights that the currently available evidence does not support the use of montelukast in preschool children with recurrent wheeze. We recommend further studies to investigate if a 'montelukast responder' phenotype exists, and how these can be easily identified in the clinical setting. What is Known: • Current guidelines recommend montelukast use in preschool children with recurrent wheeze. • A recent Cochrane review has found montelukast to be ineffective at reducing courses of oral corticosteroids for viral-induced wheeze. What is New: • This meta-analysis has examined all children with preschool wheeze and found that montelukast was not effective at preventing wheezing episodes or reducing unscheduled medical attendances. • A specific montelukast responder phenotype may exist, but such patients should be sought in larger multicentre RCTs.

Evaluating the role of leukotriene-modifying drugs in asthma management: Are their benefits 'losing in translation'?

Leukotrienes (LTs) initiate a cascade of reactions that cause bronchoconstriction and inflammation in asthma. LT-modifying drugs have been proved very effective to reduce inflammation and associated exacerbation however despite some illustrious clinical trials the usage of these drugs remains overlooked because the evidence to support their utility in asthma management has been mixed and varied between studies. Although, there are plenty of evidences which suggest that the leukotriene-modifying drugs provide consistent improvement even after just the first oral dose and reduce asthma exacerbations, the beneficial effect of these drugs has remained sparse and widely debated. And these beneficial effects are often overlooked because most of the clinical studies include a mixed population of asthmatics who do not respond to LT-modifiers equally. Therefore, in the present era of personalized medicine, it is important to properly stratify the patients and non-invasive measurements of biomarkers may warrant the possibility to characterize biological/pathological pathway to direct treatment to those who will benefit from it. Endotyping based on individual's leukotriene levels should probably ascertain a subgroup of patients that would clearly benefit from the treatment even though the trial fails to show overall significance. In this article, we have methodically evaluated contemporary literature describing the efficacy of LT-modifying drugs in the management of asthma and highlighted the importance of phenotyping the asthmatics for better treatment outcomes.

Roflumilast for asthma: Efficacy findings in non-placebo-controlled comparator and dosing studies

BACKGROUND

Roflumilast, a phosphodiesterase-4 inhibitor, has an established place in the treatment of chronic obstructive pulmonary disease. Its potential role as a treatment for asthma is unclear.

AIM

We report the results from seven double-blind, parallel group, phase II or III studies designed to compare roflumilast with two anti-inflammatory treatments, beclomethasone dipropionate (BDP) and montelukast, in patients with asthma.

METHODS

The studies of 6-12 week duration were conducted at 309 sites in Europe, North America, South Africa and Australia from 1998 to 2005. Data from 3802 patients, aged 12-70 years who received either roflumilast 100 μg, 250 μg or 500 μg once daily, BDP 400 μg or 500 μg twice daily, or 10 mg montelukast once daily was analyzed. Primary endpoints were mean change and time averaged excess area under the curve in forced expiratory volume in one second (FEV1) over the duration of the study. Secondary endpoints included change in forced vital capacity and peak expiratory flow, asthma symptoms and the concomitant use of rescue medication.

RESULTS

Roflumilast was non-inferior to BDP and montelukast and consistently increased FEV1. Use of rescue medication and all asthma symptom scores decreased significantly with all treatments, but no statistically significant between-group differences were observed. Secondary lung function endpoints generally supported the conclusions of the primary outcome measure.

CONCLUSIONS

Roflumilast improves FEV1 and asthma symptoms in patients with mild to moderate asthma, and is non-inferior compared with both BDP and montelukast. It deserves further study as a potentially effective anti-inflammatory treatment for asthma.

Asthma phenotypes: an approach to the diagnosis and treatment of asthma

I teach that "Asthma is the most treatable of all chronic diseases known to mankind." Yet, outcome data from throughout the world (emergency department visits, hospitalizations, and quality of life) indicate that the diagnosis and treatment of asthma are not optimal and need improvement. Why? First, asthma is not thought of as a complex, heterogeneous disease or syndrome that consists of different phenotypes and endotypes. Second, asthma is variable, particularly in its severity, and is influenced by known, unknown, avoidable, and unavoidable environmental factors. Third, treatment usually requires complex inhalational devices that are difficult to understand and use, and with which adherence is suboptimal. Continued education on how to appropriately use medications, particularly inhaled medications, is absolutely essential, and knowledge and access to a backup treatment plan to be initiated by the patient for an asthma flare is necessary. Fourth, assessment of asthma is primarily based on symptoms, and, at times, all symptoms are due to asthma, but many times some or all symptoms are due to unrecognized and untreated comorbid or coexisting conditions. Too often, asthma is viewed as a disease that occurs in isolation, and comorbid and coexisting conditions are not appropriately identified and treated. Allergists/immunologists are well suited to provide the type of comprehensive care required to optimize asthma outcomes for the benefit of individual patients and society.