Sedative Effects of Levocetirizine: A Systematic Review and Meta-Analysis of Randomized Controlled Studies

Analyzing the clinical efficacy and safety of levocetirizine based on its receptor occupancy, intraclass comparison and role in the treatment of CSU: an AROG consensus statement

INTRODUCTION

Chronic spontaneous urticaria (CSU) is characterized by urticaria persisting for more than 6 weeks and leading to significant morbidity. Antihistamines, especially sgAH (second generation antihistamines) are the first line of treatment for CSU.

AREAS COVERED

This consensus aimed to review the existing translational research on the receptor occupancy of antihistamines, including levocetirizine, and establish its role in the treatment of CSU. The consensus was led by the Antihistamine Receptor Occupancy Group (AROG) from India, an expert panel of twelve dermatologists from various regions with a mix of institutional and practitioner backgrounds. This consensus analyzed the existing translational research on the receptor occupancy of levocetirizine to establish its clinical efficacy and safety of levocetirizine in the treatment of CSU using the grading of recommendations assessment, development, and evaluation (GRADE) method as compared to the varied SGAH.

EXPERT OPINION

Second-generation antihistamines constitute the first step in the therapeutic ladder for managing CSU. Levocetirizine has high bioavailability, a high affinity for and occupancy of the H1 receptor, a rapid onset of action, limited distribution, and minimal hepatic metabolism. It exhibits significant anti-inflammatory effects at clinically relevant concentrations. The marked receptor occupancy translates to better efficacy as compared to similarly dosed SGAH and the lower cost of the molecule makes it an appropriate drug for chronic use. Receptor occupancy should serve as the basis of intra-class head-to-head trials for CSU.

Evidence-based use of antihistamines for treatment of allergic conditions

Available since the 1940s, H1 antihistamines are mainstay treatments for allergic conditions such as allergic rhinitis and urticaria. They function as inverse agonists that bind to the H1 receptor to inhibit histamine-induced inflammation. The older, first-generation drugs are no longer recommended for patient use because of their well-documented negative adverse effect profile. Evidence has been accumulating to support a newer generation of H1 antihistamines in oral and intranasal formulations, including in combination with intranasal corticosteroids. The literature is replete with large meta-analyses and systematic reviews establishing the safety and efficacy of second-generation H1 antihistamines in adult and pediatric allergic rhinitis populations, including combination nasal spray agents (eg, MP29-02 or MP-AzeFlu). Although intraclass differences do exist, patient preference, access, and costs should be the priority. Robust data on the regular, not as needed use of H1 antihistamines for urticaria have been published, including in the management of children and pregnant or lactating women. In addition, H1 antihistamines can be used in other related allergic conditions, such as the secondary symptoms of anaphylaxis, to provide patients with greater comfort, including in allergic asthma, depending on the individual.

Asymmetric Synthesis of Bulky N-Cyclopropylmethyl-1-aryl-1-phenylmethylamines Catalyzed by Engineered Imine Reductases

Enzymatic reduction of diphenylmethanimine derivatives has rarely been reported owing to their steric hindrance. Herein, imine reductase (IRED) from Nocardia cyriacigeorgica rationally engineered with an efficient strategy of focused rational iterative site-specific mutagenesis (FRISM) was selected for the reduction of a series of N-cyclopropylmethyl-1-aryl-1-phenylmethylimines. Two highly enantioselective IRED variants were identified, providing various bulky amine products with moderate to high yields and high ee values (up to >99%). This work provided an effective method to construct these important pharmaceutical intermediates.

Comparative Safety Profiles of Individual Second-Generation H1-Antihistamines for the Treatment of Chronic Urticaria: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

BACKGROUND

The comparative safety and/or dosing regimens of individual second-generation H1-antihistamines (sgAHs) in patients with chronic urticaria (CU) remain poorly elucidated.

OBJECTIVE

To compare the safety profiles of individual sgAHs and/or dosing regimens in adolescents or adult patients with CU using a systematic review and network meta-analysis of all available evidence.

METHODS

With limited English publications, electronic databases and gray literature were searched for randomized clinical trials from inception, with searches last updated on January 20, 2023. Relevant safety outcomes included treatment unacceptability (all-cause discontinuation), tolerability (discontinuation due to any adverse events), adverse events, serious adverse events, central nervous system (CNS) side effects, and anticholinergic side effects. Regarding the network estimates, the probability of being associated with the highest adverse outcome risk was estimated for each treatment comparison.

RESULTS

Fifty-one randomized clinical trials with 14 individual sgAHs and different dosing regimens, involving 7502 participants, were included. On the basis of the findings from network meta-analyses, variations in sgAH treatment comparisons were observed regarding the unacceptability of treatment, tolerability, adverse events, and CNS side effects. There were no statistically significant differences between the results of sgAH treatment for serious adverse events and those for anticholinergic side effects. On the basis of the ranking of safety profiles, emedastine 4 mg, mizolastine 10 mg, and cetirizine 10 mg were the top 3 ranked treatments with unfavorable safety profiles associated with CNS side effects and any adverse events.

CONCLUSIONS

These findings suggest evidence of variations in safety profiles among sgAHs for CU treatment, particularly in terms of adverse events and CNS side effects.

Current and future management of chronic spontaneous urticaria and chronic inducible urticaria

Background: Chronic urticaria (CU), characterized by ≥6 weeks of intense pruritus, remains a debilitating condition for patients. New and safe treatments are needed to manage CU recalcitrant to standard therapy. Objective: A review of the current literature of standard and novel therapeutics in the management of CU was conducted. Methods: A literature search via a medical literature data base and clinical trial data base was conducted to identify treatment options for CU and current clinical trials. Results: Second-generation antihistamines, omalizumab, and cyclosporine remain the most proven therapeutic options for CU. Dupilumab, mepolizumab, benralizumab, tezepelumab, and CDX-0159 are all undergoing clinical trials for CU. Although ligelizumab demonstrated initial promising results, a phase III study was discontinued due to a nonsuperior clinical impact compared with omalizumab. Conclusion: Novel therapies are needed for the treatment of recalcitrant CU. With a deeper understanding of the pathophysiology of CU, promising therapeutics are in clinical trials for CU.

Efficacy and Safety of Diethylcarbamazine in Treatment of Allergic Rhinitis: A Double Blind Randomised Controlled Trial

There are many evidences showing diethylcarbamazine as a potential drug for the treatment of allergic rhinitis. This study evaluated the effectiveness of diethylcarbamazine in the treatment of allergic rhinitis and compared it with montelukast and levocetirizine. This parallel double-blind randomized clinical trial was done in allergic rhinitis patients. Seven hundred and twelve participants who met the inclusion criteria and provided informed written consent were randomized and divided into 2 equal groups. Diethylcarbamazine 300 mg/day orally in divided doses was given to group A, and montelukast 10 mg and levocetirizine 5 mg/day orally at night for 21 days was given to group B. Primary outcomes were the change in symptoms, absolute eosinophil count, serum total IgE, phadiatop and response in skin prick from baseline to 21 days and 3 months after treatment. Secondary outcome was to compare it with montelukast and levocetirizine. The mean (SD) age of the patients was 33 (10.6) years, with 374 (52.5%) males and 338 (47.5%) females. There was statistically significant improvement in all the parameters in both groups. Improvement was better with diethylcarbamazine compared to montelukast and levocetirizine and the effects were sustained for 3 months in diethylcarbamazine group. The findings suggest that diethylcarbamazine is effective in the treatment of allergic rhinitis. It gives better control and is cost-effective than montelukast and levocetirizine. Trial Registration: https://www.ctri.nic.in Identifier: CTRI/2020/03/024145 registered on 20-03-2020.

Pharmacological Management of Allergic Rhinitis: A Consensus Statement from the Malaysian Society of Allergy and Immunology

The goal of allergic rhinitis (AR) management is to achieve satisfactory symptom control to ensure good quality of life. Most patients with AR are currently treated with pharmacotherapy. However, knowledge gaps on the use of pharmacotherapy still exist among physicians, particularly in the primary care setting, despite the availability of guideline recommendations. Furthermore, it is common for physicians in the secondary care setting to express uncertainty regarding the use of new combination therapies like intranasal corticosteroid plus antihistamine combinations. Inadequate treatment leads to significant reduction of quality of life that affects daily activities at home, work, and school. With these concerns in mind, a practical consensus statement was developed to complement existing guidelines on the rational use of pharmacotherapy in both the primary and secondary care settings.

Efficacy and Safety of Bilastine in the Treatment of Allergic Rhinitis: A Systematic Review and Meta-analysis

Bilastine is a non-sedating second generation H1 oral antihistamine (OAH) for treating allergic rhinitis (AR) patients. The effect of bilastine has not previously been evaluated in a meta-analysis. The aim of this review was to determine the efficacy and safety of bilastine in treating AR. An electronic literature search was performed using Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Science Direct and Google Scholar up to March 2021. Randomized controlled trials comparing bilastine with placebo and standard pharmacotherapy were included. The included studies must have diagnosis of AR established by clinicians and the outcomes must have a minimum of 2 weeks of follow-up period. The primary outcomes assessed were total symptom score (TSS), nasal symptom score (NSS) and non-nasal symptom score (NNSS). The secondary outcomes were discomfort due to rhinitis, quality of life (QOL) and adverse events. The risk of bias and quality of evidence for all studies were appraised. The meta-analysis was done using Review Manager 5.3 software based on the random-effects model. The search identified 135 records after removal of duplicates. Following screening and review of the records, fifteen full-text articles were assessed for eligibility. Five trials involving 3,329 patients met the inclusion criteria. Bilastine was superior to placebo in improving TSS, NSS, NNSS, rhinitis discomfort score and QOL but has comparable efficacy with other OAHs in TSS, NSS, NNS, rhinitis discomfort score and QOL. There was no difference in adverse effects when bilastine was compared against placebo and other OAHs except for somnolence. Bilastine has fewer incidence of somnolence compared to cetirizine. The overall quality of evidence ranged from moderate to high quality. Bilastine is effective and safe in treating the overall symptoms of AR with comparable efficacy and safety with other OAHs except somnolence. Whilst bilastine has similar efficacy to cetirizine, somnolence is notably less in bilastine.

Fexofenadine: review of safety, efficacy and unmet needs in children with allergic rhinitis

Allergic rhinitis (AR) is the most common undiagnosed chronic condition in children. Moderate/severe AR symptoms significantly impair quality of life, and cause sleep disruption, absenteeism and decreased productivity. Additionally, untreated AR predisposes children to asthma and other chronic conditions. Although intranasal corticosteroids are the most effective pharmacologic treatment for AR, oral antihistamines are often preferred. First-generation antihistamines may be chosen to relieve AR symptoms as they are inexpensive and widely available; however, they cause sedative and cardiovascular negative effects due to poor receptor selectivity. Therefore, second-generation antihistamines were developed to reduce adverse effects while retaining efficacy. There are fewer clinical trials in children than adults, therefore, efficacy and safety data is limited, particularly in children under 6 years, highlighting the need to generate these data in young children with AR. Fexofenadine, a highly selective second-generation antihistamine, effectively alleviates symptoms of AR, is non-sedating due to decreased blood-brain barrier permeability, and is devoid of cardiovascular side effects. Importantly, fexofenadine relieves the ocular symptoms of allergic conjunctivitis, which occur concomitantly with AR, improving quality of life. Overall, fexofenadine displays a favorable safety profile and results in greater treatment satisfaction in children compared with other second-generation antihistamines. This review aimed to evaluate and compare the safety and efficacy of fexofenadine with other available first- and second-generation antihistamines in children with AR.

Lachnospira is a signature of antihistamine efficacy in chronic spontaneous urticaria

Chronic spontaneous urticaria (CSU) is a mast cell-driven disease with many advances in its aetiology and pathogenesis over the past years. The main treatment of CSU is oral second-generation antihistamines. However, only an average of 50% of CSU patients responded adequately to conventional or quadruple doses of non-sedative antihistamines. Meanwhile, gut microbiota can affect the efficacy of drugs. The purpose of this study was to investigate the relationship between gut microbiota and the efficacy of antihistamines in patients with CSU. The patients with CSU were divided into responders and non-responders according to the efficacy of antihistamine monotherapy. The gut microbiota of faecal samples from 15 responders and 15 non-responders was detected by 16S rDNA sequencing, and the differential bacterial species between the two groups were verified by quantitative polymerase chain reaction (qPCR). Additional faecal samples from 30 responders and 30 non-responders were used as an extended cohort to further verify the above differential bacterial species by qPCR. Lachnospiraceae and its subordinate taxa were found to be the main differences in gut microbiota between responders and non-responders. The abundance of Lachnospira in responders was higher than that in non-responders. Lachnospira exhibits moderate diagnostic value in evaluating the efficacy of antihistamine. Lachnospira is a signature for predicting the efficacy of antihistamine in patients with CSU.

Utility of Environmental Exposure Unit Challenge Protocols for the Study of Allergic Rhinitis Therapies

PURPOSE OF REVIEW

This paper explores how the Environmental Exposure Unit (EEU) experimental model can be used to further our understanding of pharmacotherapies and immunotherapies for the treatment of allergic rhinitis (AR).

RECENT FINDINGS

EEUs are used increasingly for the study of combination therapies, immunotherapies, and novel AR treatments. A combined antihistamine/corticosteroid nasal spray formulation was seen to have a faster onset of action relative to the therapies individually in the Environmental Exposure Chamber. House dust mite sublingual immunotherapy tablets are both safe and efficacious as evaluated by the Vienna Challenge Chamber. The Kingston EEU found that a novel peptide-based immunotherapy approach to be effective in reducing grass pollen-induced AR. Lastly, nasal filters were determined to reduce seasonal AR symptoms, given out-of-season in the Denmark Environmental Exposure Unit. EEUs are controlled, replicable models that provide valuable insight into the efficacy, onset and duration of action, and dose-related impacts of AR therapeutics, with direct clinical relevance.

Idiopathic anaphylaxis: What you do not know may hurt you

Idiopathic anaphylaxis (IA), like immunologic and nonimmunologic anaphylaxis, is a life-threatening, sometimes fatal allergic disease. Although the priority is immediate recognition and initiation of treatment, long-term care planning is important to help reduce anxiety and promote healthy growth and development. Learning to recognize, manage, and stabilize the child is an essential part of improving the family dynamics. Despite advancements in the management of anaphylaxis, research has shown a need for continued patient education and training to improve timely recognition and treatment. This article focuses on elucidating the clinical presentation, theories of pathogenesis, and diagnosis, treatment, and management of IA.

Antihistamine effects and safety of fexofenadine: a systematic review and Meta-analysis of randomized controlled trials

Background

As a new generation antihistamine, fexofenadine has been widely used in allergic diseases. However, there is still a lack of collective evidence regarding the antihistamine effects and safety profiles of fexofenadine relative to other antihistamine drugs and placebo. Therefore, we aimed to systematically evaluate the antihistamine effects and safety of fexofenadine.

Methods

An electronic literature search of randomized controlled trials (RCTs) was performed using Embase, Cochrane and PubMed from establishment to January 1st, 2018. RCTs comparing the antihistamine effects or safety (adverse events, sedative effects, and cognitive/psychomotor function) of fexofenadine with either other antihistamines or placebo for healthy subjects and patients with allergy were selected.

Results

Fifty-one studies of 14,551 participants met the inclusion criteria. When compared with the first-generation antihistamines, fexofenadine produced significantly lower adverse events frequency (OR = 0.446; 95% CI: 0.214 to 0.929, P = 0.031), significantly lower sedative effects frequency (OR = 0.265; 95% CI: 0.072 to 0.976, P = 0.046) and significantly less change of all cognitive/psychomotor function. When compared with the second-generation antihistamines, fexofenadine produced significantly marginal sedative effects (OR = 0.59; 95% CI, 0.38 to 0.93; P = 0.02) and significantly less change of most of the cognitive/psychomotor function. When compared with placebo, fexofenadine produced more significant antihistamine effects.

Conclusions

Fexofenadine has a positive antihistamine effect, which is probably no worse than the second-generation antihistamines. Fexofenadine probably has a favorable safety profile, which is more likely better than that of the first-generation antihistamines. There is lack of data to support that fexofenadine has a better overall safety profile compared to the second-generation antihistamines, however, some presently available evidence on sedative effects and certain aspects of cognitive/psychomotor function favors fexofenadine. Therefore, fexofenadine may be worthy of recommendation for safety related workers.

The Effect Of Food On The Pharmacokinetic Properties And Bioequivalence Of Two Formulations Of Levocetirizine Dihydrochloride In Healthy Chinese Volunteers

PURPOSE

The aim of this study is to assess the bioequivalence of a new generic formulation and the branded formulation of levocetirizine dihydrochloride in healthy Chinese volunteers under fasting and fed conditions, and food-intake effect on the pharmacokinetic properties is also evaluated.

PATIENTS AND METHODS

Volunteers were randomly allocated into two groups to receive a single oral dose of generic formulation and branded formulation under fasting or fed conditions, respectively. Blood samples were collected at designated time points. Plasma concentrations of levocetirizine were determined by UFLC-MS/MS. Safety evaluations were carried out through the study. The main pharmacokinetic parameters of the two formulations of levocetirizine were calculated using non-compartmental analysis incorporated in WinNonlin® 7.0 software.

RESULTS

Forty-nine volunteers were enrolled; 46 completed the studies. Under fasting and fed conditions, the 90% confidence intervals for the geometric mean of generic/branded ratios were in the range of 94.75-107.24% and 99.98-114.69% for the maximum observed concentration, and 97.13-102.50% and 98.36-103.98% for the area under the concentration-time curve. As a result of food intake before administration, the reduced rate and extent of absorption of levocetirizine were observed. Both formulations were generally well tolerated, with no serious adverse reactions reported.

CONCLUSION

The two formulations demonstrated essentially identical pharmacokinetic profiles and were all well within the FDA/CFDA bioequivalence standards. Meanwhile, food intake can delay the absorption rate and reduced the bioavailability of levocetirizine in healthy Chinese volunteers.

Human H1 receptor (HRH1) gene polymorphism is associated with the severity of side effects after desloratadine treatment in Chinese patients with chronic spontaneous uticaria

H1 nonsedating antihistamines, such as desloratadine, are first-line treatment options for chronic spontaneous urticaria (CSU). However, desloratadine induces various degrees of sedation side effect in CSU patients, and no biomarkers currently exist for predicting the severity of such side effect. Herein, we evaluated the association between HRH1 gene rs901865 polymorphism and the severity of sedation side effect following desloratadine therapy in patients with CSU. We found that 20 of the 114 patients (17.50%) showed sedation side effect after desloratadine treatment, and 3 patients (2.63%) experienced serious sleepiness. The frequency of HRH1 rs901865 G allele was significantly higher in patients who experienced sedation than in patients with rs901865 A allele (p = 0.0009). Moreover, patients with the rs901865 G/G genotype suffered a more serious sedation side effect than patients with the rs901865 G/A genotype (p = 0.005). These results provide evidence that the HRH1 rs901865 G/G polymorphism is associated with severe sedation side effect after desloratadine treatment. Thus, the HRH1 rs901865 allele may potentially be used as a biomarker for predicting the severity of sedation side effect in patients suffering from CSU and treated with desloratadine.

IV Brazilian Consensus on Rhinitis - an update on allergic rhinitis

INTRODUCTION

The guidelines on allergic rhinitis aim to update knowledge about the disease and care for affected patients. The initiative called "Allergic Rhinitis and its Impact on Asthma", initially published in 2001 and updated in 2008 and 2010, has been very successful in disseminating information and evidence, as well as providing a classification of severity and proposing a systemized treatment protocol. In order to include the participation of other medical professionals in the treatment of allergic rhinitis, it is important to develop algorithms that accurately indicate what should and can be done regionally.

OBJECTIVE

To update the III Brazilian Consensus on Rhinitis - 2012, with the creation of an algorithm for allergic rhinitis management.

METHODS

We invited 24 experts nominated by the Brazilian Association of Allergy and Immunology, Brazilian Association of Otorhinolaryngology and Head and Neck Surgery and Brazilian Society of Pediatrics to update the 2012 document.

RESULTS

The update of the last Brazilian Consensus on Rhinitis incorporated and adapted the relevant information published in all "Allergic Rhinitis and its Impact on Asthma" Initiative documents to the Brazilian scenario, bringing new concepts such as local allergic rhinitis, new drugs and treatment evaluation methods.

CONCLUSION

A flowchart for allergic rhinitis treatment has been proposed.