Comparative clinical efficacy, onset and duration of action of levocetirizine and desloratadine for symptoms of seasonal allergic rhinitis in subjects evaluated in the Environmental Exposure Unit (EEU)

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.

Towards definitive management of allergic rhinitis: best use of new and established therapies

BACKGROUND

Allergic rhinitis (AR) is an inflammatory disease of the nasal mucosa impacting up to 25% of Canadians. The standard of care for AR includes a treatment plan that takes into account patient preferences, the severity of the disease, and most essentially involves a shared decision-making process between patient and provider.

BODY

Since their introduction in the 1940s, antihistamines (AHs) have been the most utilized class of medications for the treatment of AR. First-generation AHs are associated with adverse central nervous system (CNS) and anticholinergic side effects. On the market in the 1980s, newer generation AHs have improved safety and efficacy. Compared to antihistamines, intranasal corticosteroids (INCS) have significantly greater efficacy but longer onset of action. Intranasal AH and INCS combinations offer a single medication option that offers broader disease coverage and faster symptom control. However, cost and twice-per-day dosing remain a major limitation. Allergen immunotherapy (AIT) is the only disease-modifying option and can be provided through subcutaneous (SCIT) or sublingual (SLIT) routes. While SCIT has been the definitive management option for many years, SLIT tablets (SLIT-T) have also been proven to be safe and efficacious.

CONCLUSION

There is a range of available treatment options for AR that reflect the varying disease length and severity. For mild to moderate AR, newer generation AHs should be the first-line treatment, while INCS are mainstay treatments for moderate to severe AR. In patients who do not respond to INCS, a combination of intranasal AH/INCS (AZE/FP) should be considered, assuming that cost is not a limiting factor. While SCIT remains the option with the most available allergens that can be targeted, it has the potential for severe systemic adverse effects and requires weekly visits for administration during the first 4 to 6 months. SLIT-T is a newer approach that provides the ease of being self-administered and presents a reduced risk for systemic reactions. In any case, standard care for AR includes a treatment plan that takes into account disease severity and patient preferences.

Efficacy of Desloratadine and Levocetirizine in Patients with Cedar Pollen-Induced Allergic Rhinitis: A Randomized, Double-Blind Study

BACKGROUND

No comparative study of antihistamines that differ in structural system has been conducted in allergic rhinitis.

OBJECTIVE

This was a randomized, double-blind, crossover comparative study to verify the efficacy of antihistamines that differ in structural system.

METHODS

A total of 50 patients with moderate or more severe Japanese cedar pollen-induced allergic rhinitis were randomized to receive either placebo, desloratadine 5 mg (a tricyclic), or levocetirizine 5 mg (a piperazine). One dose of the study drug was orally administered at 9 pm on the day before a pollen exposure test, which was performed for 3 h (9 a.m. to 12 p.m.) to assess symptoms in an environmental challenge chamber (ECC). Nasal and ocular symptoms were compared at an airborne pollen level of 8,000 grains/m3. The primary endpoint was mean total nasal symptom score (TNSS) from 120 to 180 min in the ECC. Subjects with a difference of ≥1 in TNSS between 2 drugs were extracted to the relevant drug-responsive group.

RESULTS

The difference in TNSS from placebo was -2.42 (p < 0.0001) with levocetirizine and -1.66 (p < 0.01) with desloratadine, showing that both drugs were significantly more effective than placebo in controlling symptoms, but with no statistically significant difference between the 2 drugs. There were 12 subjects in the desloratadine-responsive group and 24 subjects in the levocetirizine-responsive group, with no contributor to response was detected.

CONCLUSION

Levocetirizine tended to control nasal symptoms more effectively than desloratadine. However, the response to each antihistamine varied among individuals and the predictors to the response are unknown.

CLINICAL TRIAL REGISTRATION NUMBER

UMIN ID: UMIN000029653.

Clinical standardization of two controlled allergen challenge facilities: The Environmental Exposure Unit and the Biogenics Research Chamber

BACKGROUND

Controlled allergen challenge facilities (CACF), in disparate geographic regions with dissimilar engineering and base populations, have historically functioned as single, independent sites in clinical allergy trials. We aimed to demonstrate "between-unit reproducibility" to allow controlled challenge trials of participants using 2 CACFs.

OBJECTIVE

To compare and standardize 2 CACFs located in Kingston, Ontario, Canada, and San Antonio, Texas, by examining participant-reported symptom severity during qualifying and treatment visits and evaluating response to treatment, while using the same allergen.

METHODS

At 2 different CACFs, participants were enrolled in a double-blind, placebo-controlled, crossover intervention trial with cetirizine 10 mg. Different distribution devices delivered common short ragweed pollen via laminar air flow and maintained an airborne concentration of 3500 ± 700 grains/m³ in both facilities. A 1-hour "sham" run with no pollen release preceded a priming exposure of 3 hours and was followed 3 days later by a qualifying/treatment 5-hour exposure. At least 14 days later, another priming exposure was followed by the crossover exposure and treatment.

RESULTS

Forty-eight and 43 subjects completed the study at Kingston and San Antonio, respectively. Demographics were similar. Fewer than 10% exhibited symptoms with sham exposure. No significant differences were found between the 2 facilities in maximal total rhinoconjunctivitis symptom score, total nasal symptom score, and total ocular symptom score, nor in areas under the curve. In both facilities, no significant effects of cetirizine 10 mg over placebo were detected.

CONCLUSION

The results were equivalent, demonstrating that the 2 CACFs can be used together in dual-center clinical trials and show the possibility of multicenter trials involving multiple CACFs.

[Allergic rhinitis: the modern aspects of therapy]

The main objectives of the present article were to systematize the modern views of the causes and risk factors of allergic rhinitis, to clarify the manner of its development, to define the leading etiological mechanism underling the pathogenesis of this condition, to consider the methods used for the diagnostics and the treatment of this disease, and to sum up the clinical experience with the use of Levocetirizine (Allerwey) for the management of allergic rhinitis. Special attention is given to the achievement and the maintenance of control of the persistent or intermittent forms of allergic rhinitis and to approaches to its treatment based on the medications registered in the Russian Federation.

Onset of Action of Azelastine Nasal Spray Compared with Mometasone Nasal Spray and Placebo in Subjects with Seasonal Allergic Rhinitis Evaluated in an Environmental Exposure Chamber

Background

The objective of this study was to determine the onset of action of azelastine hydrochloride nasal spray compared with placebo and an intranasal steroid, mometasone furoate, in subjects with seasonal allergic rhinitis (SAR).

Methods

Subjects with a history of SAR and symptomatic while exposed to ragweed pollen in an environmental exposure chamber (EEC) were randomized to azelastine nasal spray (n = 150), mometasone nasal spray (n = 150), or placebo (n = 150) and recorded total nasal symptom scores (TNSS), consisting of sneezing, nasal pruritus, rhinorrhea, and congestion, during an 8-hour study period.

Results

Azelastine nasal spray showed a statistically significant improvement in the TNSS at 15 minutes compared with placebo. The effect was durable at each time point during the 8-hour study. Azelastine nasal spray also was significantly more effective than mometasone at each time point.

Conclusion

Azelastine nasal spray has a rapid (15 minute) onset of action. Azelastine nasal spray was superior to both placebo and mometasone nasal spray in reducing nasal symptoms of SAR occurring within 8 hours after an allergen challenge.

Onset of Action of the Fixed Combination Intranasal Azelastine-Fluticasone Propionate in an Allergen Exposure Chamber

BACKGROUND

A fixed-dose combination of intranasal azelastine hydrochloride and fluticasone propionate (MP-AzeFlu) is the most effective treatment of allergic rhinitis, but its onset of action requires further investigation.

OBJECTIVE

To compare the onset of action of MP-AzeFlu with the free combination of oral loratadine (LORA) and intranasal fluticasone propionate (INFP).

METHODS

In this single-center, randomized, placebo-controlled, double-blind, double-dummy, 3-period crossover trial, allergic rhinitis symptoms were induced in asymptomatic patients by ragweed pollen challenge in an allergen environmental exposure chamber. Patients received single-dose MP-AzeFlu, LORA/INFP, or placebo and were monitored for 4 hours. The primary outcome was onset of action measured by total nasal symptom score (TNSS). Secondary measures were total ocular symptom score (TOSS), total score of the 7 nasal and ocular symptoms (T7SS), and the global visual analog scale (VAS).

RESULTS

The full analysis set included 82 patients, of which 78 completed all treatments. TNSS was significantly reduced versus placebo from 5 minutes for MP-AzeFlu and 150 minutes for LORA/INFP onward (both P < .05) till the end of assessment (0-4 hours). MP-AzeFlu reduced TNSS to a greater extent at each time point from 5 to 90 minutes (P < .05) and over the entire assessment interval (P ≤ .005) versus LORA/INFP or placebo. No statistically significant difference between LORA/INFP and placebo was observed over the assessment interval (P = .182). The onset of action of MP-AzeFlu assessed by TOSS, T7SS, and VAS was 10 minutes, 2 hours earlier than with LORA/INFP.

CONCLUSION

MP-AzeFlu had a more rapid onset of action (5 minutes) and was more effective than LORA/INFP.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Onset of action for loratadine tablets for the symptomatic control of seasonal allergic rhinitis in adults challenged with ragweed pollen in the Environmental Exposure Unit: a post hoc analysis of total symptom score

Background

Loratadine is a second-generation, non-sedating antihistamine used for the relief of allergic rhinitis symptoms. Previous studies reported that when loratadine was encapsulated, the onset of action for symptom relief was 180 min. However, unmodified loratadine tablets were not evaluated at that time. Using data from a previously published Environmental Exposure Unit (EEU) study comparing azelastine nasal spray with loratadine tablets, cetirizine tablets, and placebo, this post hoc analysis determines the onset of action of loratadine tablets (i.e. unmodified) by analyzing the total symptom score for the relief of nasal and ocular seasonal allergic rhinitis (SAR) symptoms.

Methods

A Phase IV, randomized, single-center, double-blind, placebo-controlled, double-dummy, four-way crossover study was conducted in the EEU. Seventy participants were randomized sequentially into one of the four treatments during ragweed pollen exposure. Nasal and ocular symptom scores were self-reported by the participants and recorded. The original study analysis was carried out by evaluating the nasal symptom scores only. For this post hoc analysis, both nasal and ocular data from the loratadine and placebo treatment arms were analyzed. The primary endpoint for this analysis was the onset of action of loratadine as measured by the change in total symptom score (TSS) from baseline in comparison to placebo. The onset of ocular symptom relief using the total ocular symptom score (TOSS) was also reported.

Results

Loratadine tablets demonstrated a significant and durable improvement in both TSS (P = .005) and TOSS (P = .013) at 75 min post-treatment administration compared to placebo. The mean proportion of participants reporting none or mild for all component symptoms of TSS and TOSS at 75 min and thereafter was significantly higher in the loratadine (TSS, P = .0005; TOSS, P ≤ .0001) vs. placebo treatment arm.

Conclusions

The onset of action of loratadine tablets was 75 min for the relief of nasal and ocular symptoms in adults with SAR. These results suggest a faster onset of action for loratadine tablets (75 min) compared to previously reported studies which were conducted with modified (i.e. gelatin-encapsulated) loratadine tablets (180 min).

Trial registration Clinicaltrials.gov identifier NCT00561717

Electronic supplementary material

The online version of this article (10.1186/s13223-017-0227-4) contains supplementary material, which is available to authorized users.

Controlled Allergen Challenge Facilities and Their Unique Contributions to Allergic Rhinitis Research

The aim of this study is to review advances in basic and clinical allergic rhinitis (AR) research over the past decade that have been conducted using controlled allergen challenge facility (CACF) models of allergen challenge. Databases, including PubMed, Medline, and Web of Science were searched for articles employing an ambient pollen exposure in a controlled facility to study AR, published between 2004 and the present date, using the terms as follows: CACF, Environmental Exposure Unit (EEU), Vienna Challenge Chamber (VCC), Fraunhofer Institute Environmental Challenge Chamber, Atlanta Allergen Exposure Unit, Biogenics Research Chamber, Allergen BioCube, Chiba and Osaka Environmental Challenge Chamber, exposure unit, challenge chamber, or environmental exposure chamber. Articles were then selected for relevance to the goals of the present review, including important contributions toward clinical and/or basic science allergy research. CACFs offer sensitive, specific, and reproducible methodology for allergen challenge. They have been employed since the 1980s and offer distinct advantages over traditional in-season multicentre trials when evaluating new treatments for AR. They have provided clinically applicable efficacy and pharmacologic information about important allergy medications, including antihistamines, decongestants, antileukotrienes, immunotherapies, and nasal steroids. CACF models have also contributed to basic science and novel/experimental therapy research. To date, no direct studies have been conducted comparing outcomes from one CACF to another. Over the past decade, CACF models have played an essential role in investigating the pathophysiology of AR and evaluating new therapies. The future opportunities for this model continue to expand.

Clinical practice guideline: Allergic rhinitis

OBJECTIVE

Allergic rhinitis (AR) is one of the most common diseases affecting adults. It is the most common chronic disease in children in the United States today and the fifth most common chronic disease in the United States overall. AR is estimated to affect nearly 1 in every 6 Americans and generates $2 to $5 billion in direct health expenditures annually. It can impair quality of life and, through loss of work and school attendance, is responsible for as much as $2 to $4 billion in lost productivity annually. Not surprisingly, myriad diagnostic tests and treatments are used in managing this disorder, yet there is considerable variation in their use. This clinical practice guideline was undertaken to optimize the care of patients with AR by addressing quality improvement opportunities through an evaluation of the available evidence and an assessment of the harm-benefit balance of various diagnostic and management options.

PURPOSE

The primary purpose of this guideline is to address quality improvement opportunities for all clinicians, in any setting, who are likely to manage patients with AR as well as to optimize patient care, promote effective diagnosis and therapy, and reduce harmful or unnecessary variations in care. The guideline is intended to be applicable for both pediatric and adult patients with AR. Children under the age of 2 years were excluded from the clinical practice guideline because rhinitis in this population may be different than in older patients and is not informed by the same evidence base. The guideline is intended to focus on a limited number of quality improvement opportunities deemed most important by the working group and is not intended to be a comprehensive reference for diagnosing and managing AR. The recommendations outlined in the guideline are not intended to represent the standard of care for patient management, nor are the recommendations intended to limit treatment or care provided to individual patients.

ACTION STATEMENTS

The development group made a strong recommendation that clinicians recommend intranasal steroids for patients with a clinical diagnosis of AR whose symptoms affect their quality of life. The development group also made a strong recommendation that clinicians recommend oral second-generation/less sedating antihistamines for patients with AR and primary complaints of sneezing and itching. The panel made the following recommendations: (1) Clinicians should make the clinical diagnosis of AR when patients present with a history and physical examination consistent with an allergic cause and 1 or more of the following symptoms: nasal congestion, runny nose, itchy nose, or sneezing. Findings of AR consistent with an allergic cause include, but are not limited to, clear rhinorrhea, nasal congestion, pale discoloration of the nasal mucosa, and red and watery eyes. (2) Clinicians should perform and interpret, or refer to a clinician who can perform and interpret, specific IgE (skin or blood) allergy testing for patients with a clinical diagnosis of AR who do not respond to empiric treatment, or when the diagnosis is uncertain, or when knowledge of the specific causative allergen is needed to target therapy. (3) Clinicians should assess patients with a clinical diagnosis of AR for, and document in the medical record, the presence of associated conditions such as asthma, atopic dermatitis, sleep-disordered breathing, conjunctivitis, rhinosinusitis, and otitis media. (4) Clinicians should offer, or refer to a clinician who can offer, immunotherapy (sublingual or subcutaneous) for patients with AR who have inadequate response to symptoms with pharmacologic therapy with or without environmental controls. The panel recommended against (1) clinicians routinely performing sinonasal imaging in patients presenting with symptoms consistent with a diagnosis of AR and (2) clinicians offering oral leukotriene receptor antagonists as primary therapy for patients with AR. The panel group made the following options: (1) Clinicians may advise avoidance of known allergens or may advise environmental controls (ie, removal of pets; the use of air filtration systems, bed covers, and acaricides [chemical agents formulated to kill dust mites]) in patients with AR who have identified allergens that correlate with clinical symptoms. (2) Clinicians may offer intranasal antihistamines for patients with seasonal, perennial, or episodic AR. (3) Clinicians may offer combination pharmacologic therapy in patients with AR who have inadequate response to pharmacologic monotherapy. (4) Clinicians may offer, or refer to a surgeon who can offer, inferior turbinate reduction in patients with AR with nasal airway obstruction and enlarged inferior turbinates who have failed medical management. (5) Clinicians may offer acupuncture, or refer to a clinician who can offer acupuncture, for patients with AR who are interested in nonpharmacologic therapy. The development group provided no recommendation regarding the use of herbal therapy for patients with AR.

Comparative Study of Apo-Cetirizine Single Therapy and Intermittent Sequential Therapy with Cetirizine, Loratadine and Chlorpheniramine in Allergic Rhinitis

There are limited numbers of articles, studying combined use of antihistamines. In this study, we compare single therapy of Apo-Cetirizine with a new regimen of intermittent sequential therapy with cetirizine, loratadine and chlorpheniramine in treatment of seasonal allergic rhinitis. This randomized clinical trial was performed between April and September at the peak prevalence of seasonal allergic rhinitis. Fifty-four eligible patients diagnosed clinically to have seasonal allergic rhinitis were randomized in two groups: 24 cases in single therapy arm, received Apo-Cetirizine 10 mg tablet daily and in other arm, 30 patients received sequential regimen of cetirizine 10 mg tablet, loratadine 10 mg tablet and chlorpheniramine 4 mg tablet, one tablet each day. Major Symptom Complex Score (MSCS) and Total Symptom Complex Score (TSCS) of patients were recorded before treatment and after 30 days of treatment in two groups. The average post-treatment MSCS and TSCS in combination therapy group showed better improvement than single therapy group but difference was not statistically significant (p value = 0.053 and p value = 0.104 respectively). Combination therapy regimen was better in improvement of nasal congestion (p value = 0.006). There were no significant difference between two groups in efficacy, side effects and patient's satisfaction. Combination therapy would be effective on a wide spectrum of symptoms with lower price and theoretically offers lower chance of tolerance and re-appearance of complaints.

Efficacy of fluticasone furoate nasal spray and levocetirizine in patients with Japanese cedar pollinosis subjected to an artificial exposure chamber

OBJECTIVE

This study investigated the clinical efficacy of a combination therapy of levocetirizine (LCTZ) and fluticasone furoate nasal spray (FFNS), compared with LCTZ monotherapy, for the suppression of seasonal allergic rhinitis (SAR) symptoms induced in an artificial exposure chamber.

METHODS

This study was a single-center, placebo-controlled, randomized, 3-way cross-over comparative study performed in 42 Japanese cedar pollinosis patients. These subjects received (1) LCTZ plus FFNS (combination group), (2) LCTZ plus FFNS placebo (monotherapy group), or (3) LCTZ placebo plus FFNS placebo (placebo group) once on the night prior to exposure, with a 1-week washout period between exposures. Nasal (sneezing, rhinorrhea, nasal congestion, and itchy nose) and ocular (eye itching and tearing) symptoms were recorded every 15 min, and the number of sneezes, nose blowing events, and the amount of nasal secretions were measured during exposure. The primary end-point was the cumulative incidence of SAR symptoms during exposure and the 'ime to occurrence of symptoms'. The secondary end-points were the total nasal symptom score, the ocular symptom score, the amount of nasal discharge, and the number of sneezes and nose blowing events.

RESULTS

At all the measurement points, the lowest cumulative incidences for the nasal symptoms were observed in the combination group, followed by the monotherapy and placebo groups. All the subjects in the placebo group developed nasal symptoms within 2 h after pollen exposure, while three and eight subjects in the monotherapy and combination groups, respectively, did not develop any nasal symptoms during exposure. In addition, combination therapy delayed the onset of symptoms.

CONCLUSIONS

The results demonstrated that combination therapy with FFNS and LCTZ significantly suppressed the induced SAR symptoms and delayed the onset of symptoms compared with LCTZ monotherapy and placebo. Although the conditions of the allergen challenge study using an exposure chamber are different from those in real life, combination therapy with FF and LCTZ was confirmed to be an effective treatment for SAR.

Pharmacology of antihistamines

H1-antihistamines, the mainstay of treatment for urticaria, were developed from anticholinergic drugs more than 70 years ago. They act as inverse agonists rather than antagonists of histamine H1-receptors which are members of the G-protein family. The older first generation H1-antihistamines penetrate readily into the brain to cause sedation, drowsiness, fatigue and impaired concentration and memory causing detrimental effects on learning and examination performance in children and on impairment of the ability of adults to work and drive. Their use should be discouraged. The newer second-generation H1-antihistamines are safer, cause less sedation and are more efficacious. Three drugs widely used for symptomatic relief in urticaria, desloratadine, levocetirizine and fexofenadine are highlighted in this review. Of these levocetirizine and fexofenadine are the most potent in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals, whereas fexofenadine has a relatively short duration of action and may be required to be given twice daily for all round daily protection. Although desloratadine is less potent, it has the advantages of rarely causing somnolence and having a long duration of action.

A four-way, double-blind, randomized, placebo controlled study to determine the efficacy and speed of azelastine nasal spray, versus loratadine, and cetirizine in adult subjects with allergen-induced seasonal allergic rhinitis

Background

Azelastine has been shown to be effective against seasonal allergic rhinitis (SAR). The Environmental Exposure Unit (EEU) is a validated model of experimental SAR. The objective of this double-blind, four-way crossover study was to evaluate the onset of action of azelastine nasal spray, versus the oral antihistamines loratadine 10 mg and cetirizine 10 mg in the relief of the symptoms of SAR.

Methods

70 participants, aged 18-65, were randomized to receive azelastine nasal spray, cetirizine, loratadine, or placebo after controlled ragweed pollen exposure in the EEU. Symptoms were evaluated using the total nasal symptom score (TNSS). The primary efficacy parameter was the onset of action as measured by the change from baseline in TNSS.

Results

Azelastine displayed a statistically significant improvement in TNSS compared with placebo at all time points from 15 minutes through 6 hours post dose. Azelastine, cetirizine, and loratadine reduced TNSS compared to placebo with an onset of action of 15 (p < 0.001), 60 (p = 0.015), and 75 (p = 0.034) minutes, respectively. The overall assessment of efficacy was rated as good or very good by 46% of the participants for azelastine, 51% of the participants for cetirizine, and 30% of the participants for loratadine compared to 18% of the participants for placebo.

Conclusions

Azelastine’s onset of action for symptom relief was faster than that of cetirizine and loratadine. The overall participant satisfaction in treatment with azelastine is comparable to cetirizine and statistically superior to loratadine. These results suggest that azelastine may be preferential to oral antihistamines for the rapid relief of SAR symptoms.

Safety evaluation of desloratadine in allergic rhinitis

INTRODUCTION

Desloratadine is a biologically active metabolite of second-generation antihistamine loratadine. It is also indicated for the treatment of allergic diseases, including allergic rhinitis.

AREAS COVERED

A Medline search was conducted to identify preclinical and clinical studies of desloratadine. This was supplemented with additional articles obtained from online sources. The focus of this review is on the safety profile of desloratadine.

EXPERT OPINION

The review of these data indicates that the safety profile of desloratadine is similar to other second-generation antihistamines. Desloratadine is highly selective for histamine H₁-receptors, does not cross the blood-brain barrier (BBB), and has minimal adverse events (very low sedation rate), with a better safety and tolerability than first-generation antihistamines. Desloratadine is safe and well tolerated without having central nervous system (CNS) or cardiovascular effects and with low drug interaction.

Pharmacology of antihistamines

This article reviews the molecular biology of the interaction of histamine with its H1-receptor and describes the concept that H1-antihistamines are not receptor antagonists but are inverse agonists i.e. they produce the opposite effect on the receptor to histamine. It then discourages the use of first-generation H1-antihistamines in clinical practice today for two main reasons. First, they are less effective than second generation H1-antihistamines. Second, they have unwanted side effects, particularly central nervous system and anti-cholinergic effects, and have the potential for causing severe toxic reactions which are not shared by second-generation H1-antihistamines. There are many efficacious and safe second-generation H1-antihistamines on the market for the treatment of allergic disease. Of the three drugs highlighted in this review, levocetirizine and fexofenadine are the most efficacious in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals while fexofenadine has a relatively short duration of action requiring twice daily administration for full all round daily protection. While desloratadine is less efficacious, it has the advantages of rarely causing somnolence and having a long duration of action. Lastly, all H1-antihistamines have anti-inflammatory effects but it requires regular daily dosing rather than dosing 'on-demand' for this effect to be clinically demonstrable.

Pharmacology of antihistamines

This article reviews the molecular biology of the interaction of histamine with its H₁-receptor and describes the concept that H₁-antihistamines are not receptor antagonists but are inverse agonists i.e. they produce the opposite effect on the receptor to histamine. It then discourages the use of first-generation H₁-antihistamines in clinical practice today for two main reasons. First, they are less effective than second generation H₁-antihistamines. Second, they have unwanted side effects, particularly central nervous system and anti-cholinergic effects, and have the potential for causing severe toxic reactions which are not shared by second-generation H₁-antihistamines. There are many efficacious and safe second-generation H₁-antihistamines on the market for the treatment of allergic disease. Of the three drugs highlighted in this review, levocetirizine and fexofenadine are the most efficacious in humans in vivo. However, levocetirizine may cause somnolence in susceptible individuals while fexofenadine has a relatively short duration of action requiring twice daily administration for full all round daily protection. While desloratadine is less efficacious, it has the advantages of rarely causing somnolence and having a long duration of action. Lastly, all H₁-antihistamines have anti-inflammatory effects but it requires regular daily dosing rather than dosing 'on-demand' for this effect to be clinically demonstrable.

Improving SAR symptoms with levocetirizine: evaluating active and placebo effects in pollen challenge vs. natural exposure studies

OBJECTIVE

Despite a plethora of published data on levocetirizine, no meta-analyses exist on the effect of study design, and covariates like age, gender, and baseline symptom severity on treatment response. The objective of this study was the efficacy of levocetirizine 5  mg tablets and matching placebo at reducing allergy symptoms in adult subjects with seasonal allergic rhinitis under various pollen exposure study conditions and by age, gender and baseline symptom severity.

METHODS

This was a meta-analysis of original reports from randomized, double-blind, placebo-controlled studies. Clinical studies without detailed reports, open-label, non-randomized and non-controlled studies, or paediatric studies, were excluded. Study subjects were divided into an environmental exposure (EE) group or a natural exposure (NE) group.

RESULTS

Data from 3640 subjects were analysed (n = 2174 for levocetirizine, n = 1466 for placebo). The overall results confirmed the efficacy of levocetirizine 5  mg, with an approximately 40% symptom score improvement from baseline, in both the EE and NE groups. While levocetirizine showed no gender- or age-related differences in efficacy, female subjects responded better to placebo in the EE, but not in the NE group; younger subjects (<30 years of age) responded less favourably to placebo compared with older subjects (≥ 50 years of age). Levocetirizine was consistently superior to placebo regardless of baseline symptom score levels. The highest significance levels between the active and placebo groups were observed in subjects sensitized to animal dander and grass.

CONCLUSIONS

Differences between an oral antihistamine and placebo in clinical studies of allergic rhinitis might be due to a different response to placebo rather than to the active drug. Levocetirizine seems to have consistent efficacy regardless of age, gender, and baseline scores.

Levocetirizine: a modern H1-antihistamine for the treatment of allergic rhinitis

Levocetirizine is the latest of the H(1)-antihistamines indicated for adults and children (as young as 2 years old) suffering from allergic rhinitis and chronic idiopathic urticaria. Currently, it is the only therapy registered for treatment of persistent allergic rhinitis, as defined by the Allergic Rhinitis & its Impact on Asthma guidelines. Pharmacologic studies have shown levocetirizine to have a more favorable pharmacokinetic/pharmacodynamic profile than other commonly employed H(1)-antihistamines. This reflects its superiority in controlling the symptoms of seasonal, perennial and persistent allergic rhinitis in well-controlled trials. Clinical trials and postmarketing surveillance have indicated that levocetirizine is safe and well tolerated, and leads to clinically significant improvements in the quality of life of patients. It is also reported to reduce comorbidities as well as overall treatment costs when administered continuously over the longterm.

Safety and efficacy of desloratadine in subjects with seasonal allergic rhinitis or chronic urticaria: results of four postmarketing surveillance studies

BACKGROUND AND OBJECTIVE

Allergic rhinitis (AR) and chronic urticaria (CU) are common diseases with symptoms that impair quality of life. Second-generation antihistamines (e.g. cetirizine, desloratadine, fexofenadine, loratadine and mizolastine) are recommended first-line treatment for both conditions; however, studies of clinically relevant differences among these agents are lacking. The aim of this investigation was to evaluate the safety, tolerability and efficacy of desloratadine 5 mg once daily in four postmarketing surveillance studies in subjects with seasonal AR (SAR) or chronic idiopathic urticaria (CIU) in real-world clinical practice settings.

METHODS

This programme of prospective surveillance studies was conducted in Germany between February 2001 and March 2002 in allergy; dermatology; ear, nose and throat; or general practice settings. Subjects (total number 77 880) were aged > or =12 years and met the requirements for treatment of SAR or CIU with desloratadine as outlined in the package insert. All subjects received oral desloratadine 5 mg once daily for a mean duration of up to 40.4 days. Adverse events (AEs) were reported throughout the studies; serious AEs were recorded for up to 30 days after treatment. Investigators and subjects both rated tolerability at the end of treatment. Symptom severity and sleep and daily activity impairment were evaluated at baseline and after treatment using 4-point scales (0 = none; 1 = mild; 2 = moderate; 3 = severe). A post hoc subanalysis assessed desloratadine efficacy and onset of symptom relief in subjects who had received monotherapy with another second-generation antihistamine.

RESULTS

A total of 386 AEs were reported by 287 subjects (0.37%) in the four studies. The most commonly reported treatment-related AEs were fatigue (0.07%), headache (0.07%), dry mouth (0.04%) and nausea (0.03%). Tolerability was rated as excellent/good by 99.1% of investigators and 98.5% of subjects. Desloratadine therapy significantly reduced nasal and ocular symptom severity, itching and wheals, and sleep and activity disruption (p < 0.0001), as indicated by a reduction in mean total and individual symptom scores, and reported impairment of sleep and daily activities. The efficacy of desloratadine was rated as significantly greater by 59.4-88.0% of subjects who had previously received monotherapy with cetirizine, fexofenadine, loratadine or mizolastine (p < 0.01 for all). The percentage of subjects who rated onset of symptom relief with desloratadine as faster than previous treatment ranged from 51.6% to 82.4%.

CONCLUSION

Desloratadine was safe, well tolerated and efficacious in this series of surveillance studies. A post hoc analysis of subjects who had received previous monotherapy with a second-generation antihistamine found that most subjects rated efficacy as higher than their previous treatment, with a faster onset of symptom relief.

A review of the efficacy of desloratadine, fexofenadine, and levocetirizine in the treatment of nasal congestion in patients with allergic rhinitis

BACKGROUND

Nasal congestion is the most troublesome symptom of allergic rhinitis (AR). First-generation and older second-generation antihistamines, while effective against nasal itching, sneezing, and rhinorrhea, have limited efficacy in relieving nasal congestion.

OBJECTIVE

This review included nasal challenge studies and clinical trials that reported the effects on nasal congestion of the newer second-generation antihistamines desloratadine, fexofenadine, and levocetirizine.

METHODS

MEDLINE and EMBASE were searched for nasal challenge studies and clinical trials published in English between January 1, 1991, and January 31, 2009, using the following terms, alone or in combination: antihistamines, second-generation antihistamines, allergic rhinitis, intermittent allergic rhinitis, perennial allergic rhinitis, persistent allergic rhinitis, seasonal allergic rhinitis, nasal challenge, nasal blockage, and nasal congestion. Studies that were not active or placebo controlled, that did not evaluate change in nasal congestion scores, or that focused on treatments other than desloratadine, fexofenadine, and levocetirizine for nasal congestion associated with AR were excluded.

RESULTS

Twenty-six clinical trials met the criteria for inclusion in the review. In 11 placebo-controlled trials that included objective assessment of nasal congestion, desloratadine, fexofenadine, and levocetirizine were associated with reductions in the severity of nasal congestion through maintenance of nasal airflow. The mean AUC for nasal airflow over 6 hours was significantly greater with desloratadine compared with placebo in 3 studies (P < 0.05); placebo-controlled trials of fexofenadine and levocetirizine had similar results. In 25 placebo- and active-controlled trials that reported subject-rated symptom scores, the 3 newer antihistamines were efficacious in the treatment of nasal congestion associated with AR. In 10 trials that reported objective and/or subjective measures, desloratadine was associated with significant improvements in nasal congestion compared with placebo (P < or = 0.05), beginning as early as the first 2 hours after allergen challenge. Fexofenadine was associated with significantly lower nasal congestion scores compared with placebo in 4 studies (P <- 0.05); nasal congestion scores were significantly reduced with levocetirizine in 3 placebo-controlled trials (P < or = 0.005).

CONCLUSIONS

In the studies reviewed, desloratadine, fexofenadine, and levocetirizine were effective in relieving the nasal congestion associated with AR compared with placebo. This effect began as early as day 2 and was consistent and progressive throughout treatment. Desloratadine, fexofenadine, and levocetirizine are appropriate options for the treatment of nasal congestion in patients with AR.

Efficacy of loratadine-montelukast on nasal congestion in patients with seasonal allergic rhinitis in an environmental exposure unit

BACKGROUND

Nasal congestion is considered to be one of the most bothersome symptoms of allergic rhinitis (AR) and often the most difficult to treat. Oral therapies providing safe, effective, and reliable relief of AR symptoms, including nasal congestion, are limited.

OBJECTIVE

To evaluate the efficacy of a single dose of loratadine-montelukast (10 mg/10 mg) vs placebo and phenylephrine (10 mg) in relieving nasal congestion over 6 hours after ragweed pollen exposure in the environmental exposure unit at the Kingston General Hospital.

METHODS

After a screening visit and up to 6 priming visits, patients who met minimum symptom requirements during ragweed pollen exposure were randomized to receive loratadine-montelukast, phenylephrine, or placebo. Patients evaluated nasal congestion and other symptoms of AR and measured peak nasal inspiratory flow before dosing and at 20-minute intervals during the subsequent 8 hours of pollen exposure.

RESULTS

During the first 6 hours after treatment (primary end point), loratadine-montelukast treatment resulted in greater improvement in the mean nasal congestion score vs placebo (P = .007) and phenylephrine (P < .001). Loratadine-montelukast was more effective than placebo (P < or = .02) and phenylephrine (P < or = .002) in relieving total symptoms, nasal symptoms, and nonnasal symptoms and in improving peak nasal inspiratory flow. There were no statistically significant differences between phenylephrine and placebo for any measures. Fewer patients in the loratadine-montelukast group (3.9%) reported adverse events than in the phenylephrine (7.9%) and placebo (7.1%) groups; most adverse events were mild or moderate.

CONCLUSIONS

Loratadine-montelukast was more effective than placebo and phenylephrine in relieving nasal congestion and other nasal and nonnasal symptoms resulting from ragweed pollen exposure. There was no statistically significant difference between phenylephrine and placebo.

Once daily levocetirizine for the treatment of allergic rhinitis and chronic idiopathic urticaria

Levocetirizine is the pharmacologically active enantiomer of cetirizine. It is a potent histamine H-1 receptor antagonist with anti-inflammatory and antiallergic properties. The review analyses the levocetirizine's properties in terms of safety and efficacy both in allergic rhinitis and urticarioid syndromes.

Efficacy comparison of levocetirizine vs montelukast in ragweed sensitized patients

BACKGROUND

To date, no adequate data are available on direct comparison of the efficacy of levocetirizine, a recently approved histamine1-antihistamine, with that of a leukotriene antagonist in the treatment of seasonal allergic rhinitis (SAR) symptoms.

OBJECTIVE

To compare the efficacy of therapeutic doses of 5 mg of levocetirizine and 10 mg of montelukast in ragweed sensitized patients.

METHODS

A randomized, double-blind, placebo-controlled, parallel-group study was conducted between July and October 2006. Symptomatic patients with SAR were exposed to ragweed pollen under controlled conditions in an environmental exposure chamber for 4 to 5 hours after treatment with 5 mg of levocetirizine, 10 mg of montelukast, or matched placebo on 2 consecutive days. The mean change from baseline in pollen-induced rhinitis symptoms, expressed as a major symptoms complex (MSC) score (sum of scores for rhinorrhea, itchy nose, sniffles, nose blows, sneezes, and watery eyes), in period 1 (first 5 hours after first drug intake) was the primary efficacy outcome.

RESULTS

A total of 611 patients were screened, of whom 403 were randomized to receive treatment (102 placebo, 152 levocetirizine, and 149 montelukast). The MSC score in period 1 was progressively decreased to a significantly greater extent in the levocetirizine group compared with the montelukast and placebo groups (adjusted mean differences, -2.18 [95% confidence interval, -3.35 to -1.01; P < .001] and -2.22 [95% confidence interval, -3.51 to -0.92; P < .001] for levocetirizine vs montelukast and vs placebo, respectively). The effect of 10 mg of montelukast was not significantly different compared with placebo. Levocetirizine also achieved a significantly faster onset of action within 2.5 hours of administration. Both products were well tolerated.

CONCLUSIONS

This study in an environmental exposure chamber confirms the therapeutic efficacy of 5 mg of levocetirizine in improving symptoms of SAR, which was superior to 10 mg of montelukast.

Allergic rhinitis in family practice: the role of levocetirizine in clinical care

Allergic rhinitis is one of the most common presentations of allergic disorders in the United States, affecting more than 20% of the population. Chronic rhinitis affects patients' quality of life and exacerbates comorbid conditions. Its widespread burden affects society by substantially decreasing worker and scholastic productivity. Allergic rhinitis is typically managed with pharmacotherapy to alleviate symptoms and control comorbid conditions, yet many of these agents carry their own burden due to bothersome and sometimes severe side effects that can compromise patient safety. A new generation of non- or less-sedating antihistamines has recently emerged. These agents offer the promise of enhanced efficacy and tolerability. Of these agents, levocetirizine is the latest antihistamine introduced in the United States. It appears to be safe and effective for the treatment of allergic rhinitis. In addition to covering the above topics, this article reviews the value of levocetirizine for the treatment of allergic rhinitis based on its pharmacologic and pharmacokinetic profile, its efficacy compared with placebo and other new-generation antihistamines, and its safety and tolerability.

Pharmacoeconomics of levocetirizine in allergic rhinitis and chronic idiopathic urticaria: considerations for the USA

BACKGROUND

Levocetirizine, a recent, second-generation oral antihistamine, was approved by the US FDA in May 2007 to treat symptoms of allergic rhinitis and chronic idiopathic urticaria.

OBJECTIVE

To review the economic literature for levocetirizine.

METHODS

Two reviewers conducted a systematic review of the literature to identify abstracts that met the inclusion criteria. Abstracts that were considered acceptable were retrieved with full text for further assessment.

RESULTS

A total of 82 potential studies were identified. After reviewing abstracts, 11 articles were preselected for potential inclusion. Of the 11 full-text articles, three articles met the inclusion criteria.

CONCLUSION

The pharmacoeconomic literature for levocetirizine was limited. The findings were consistent across the literature, suggesting levocetirizine improved outcomes, leading to incremental cost savings and cost-effectiveness. Since many of the available levocetirizine data come from European studies, differences in practice patterns and medical resources should be considered when extrapolating data to a US clinical setting.

Effectiveness of desloratadine 5 mg once daily in patients with symptoms of seasonal allergic rhinitis: results of a Canadian multicenter, open-label trial

BACKGROUND

Seasonal allergic rhinitis (SAR) is an inflammatory response to seasonal allergens. Desloratadine, a once-daily selective histamine H(1)-receptor antagonist, has been reported to be efficacious in relieving symptoms of SAR in controlled clinical trials. However, to assess the actual effectiveness of a drug, it is important to examine information about its use in routine clinical practice.

OBJECTIVE

The Partners in Allergy Control and Therapy (PACT) study examined the effectiveness of desloratadine in patients with SAR symptoms receiving treatment in a community setting of primary care physicians in Canada.

METHODS

Patients with symptoms of SAR received desloratadine 5 mg once daily for 7 days during the spring-summer allergy season (April-July 2002). Patients rated their SAR symptoms along with their physicians by completing a questionnaire at baseline and day 7. Nasal, ocular, respiratory, and overall symptoms were rated on a scale of 0 (no symptoms evident) to 3 (severe/interfere with activities of daily living and/or sleeping). Physicians were asked to keep a record of adverse events reported by patients. The Wilcoxon signed-rank test was used to evaluate symptom severity scores. A 2-way (time x treatment), repeated measures, mixed analysis of variance (ANOVA) model was constructed to assess differences in variables over time.

RESULTS

A total of 6829 patients participated in the study. Patients reported nasal stuffiness/congestion as their most severe symptom. Just over half (50.1%) of patients were receiving another medication for SAR at study entry; 29.7% were receiving an intranasal corticosteroid. After 7 days of treatment with desloratadine, individual symptom scores and overall symptom scores were significantly reduced compared with baseline (all scores, P<0.001). An improvement in nasal/stuffiness/ congestion was reported by 88.0% of patients. The ANOVA detected a statistically significant incremental benefit with desloratadine and an intranasal corticosteroid compared with desloratadine monotherapy (P<0.001). No severe adverse events were reported.

CONCLUSION

Desloratadine 5 mg once daily was associated with significant improvement in symptoms of SAR, and appeared to provide additional benefit in relieving moderate to severe nasal stuffiness/congestion in 6786 patients receiving 7-day treatment in an actual practice setting of primary care physicians in Canada.

The safety and efficacy of desloratadine for the management of allergic disease

Allergic disease is an increasing problem worldwide. Allergic rhinitis, an inflammatory response to an allergen, affects an estimated 20-40 million people in the US, while chronic idiopathic urticaria is a dermatoallergic condition that affects 0.1-3% of people in the US and Europe. The primary goals of treatment for allergic rhinitis are to reduce symptoms, which include sneezing, rhinorrhoea and nasal congestion, improve quality of life and prevent the sequelae associated with this disease, while the goal for chronic idiopathic urticaria is the rapid and prolonged control of symptoms. Quantitatively, histamine is the most abundant mediator present during an allergic episode - thus, antihistamines (historically called histamine H(1) receptor antagonists, now called H(1) receptor inverse agonists) are a first-line defense against allergic rhinitis and chronic idiopathic urticaria. Although first-generation antihistamines can cause sedation and cognitive impairment, second-generation antihistamines are relatively non-sedating and free of such adverse events owing to their comparative inability to penetrate the blood-brain barrier. Desloratadine is one such second-generation antihistamine and is indicated for the treatment of allergic diseases, including allergic rhinitis and chronic idiopathic urticaria. It has proven efficacy against the symptoms associated with seasonal and perennial allergic rhinitis, including nasal congestion, and chronic idiopathic urticaria. As a result, it has been shown to improve patients' quality of life. The safety and efficacy profiles of desloratadine are well established, and published postmarketing analyses have assessed >54 000 patients. Although earlier second-generation antihistamines have been associated with cardiovascular adverse effects, desloratadine has been shown to be safe and well tolerated at nine times the recommended dose. In addition, it has been shown to not interact with concomitantly administered drugs and food. Overall, current data indicate that desloratadine is a safe and effective treatment for allergic diseases.

Clinical efficacy of probiotic Bifidobacterium longum for the treatment of symptoms of Japanese cedar pollen allergy in subjects evaluated in an environmental exposure unit

BACKGROUND

Japanese cedar pollinosis (JCPsis) affects nearly one in six Japanese. Oral administration of Bifidobacterium longum BB536 has been shown to be effective in relieving JCPsis symptoms during the pollen season.

METHODS

This double- two-way crossover study was designed to evaluate the efficacy of BB536 on reducing symptoms in JCPsis patients exposed to Japanese cedar pollen (JCP) in an environmental exposure unit (EEU) outside of the normal JCP season. After a 1-week run-in period, subjects (n=24) were randomly allocated to receive BB536 powder (approximately 5x1010) or placebo twice a day for 4 weeks. After a 2-week washout period, subjects were crossed over to another 4 weeks of intake. At the end of each intake period, subjects received controlled JCP exposure for 4 hours in the EEU. Symptoms were self-rated 30 minutes before and every 30 minutes during the exposures. From the first day of exposure through the next 5 successive days, participants self-rated their delayed symptoms and medication uses. Blood samples were taken before the exposures. The mean JCP levels for exposures were 6500 to 7000 grains/m3 air.

RESULTS

In comparison with placebo, BB536 intake significantly reduced the ocular symptom scores during JCP exposures. Evaluating delayed symptoms after exposures indicated that scores for disruption of normal activities were significantly lower in the BB536 group compared with the placebo group. Prevalence of medication use was markedly reduced by BB536 intake.

CONCLUSIONS

These results suggest the potential beneficial effect of BB536 in relieving symptoms of JCP allergy.

Onset of action of fexofenadine hydrochloride 60 mg/pseudoephedrine hydrochloride 120 mg in subjects aged 12 years with moderate to severe seasonal allergic rhinitis: a pooled analysis of two single-dose, randomized, double-blind, placebo-controlled allergen exposure unit studies

BACKGROUND

The onset of action of antihistamine-decongestant combinations is an important factor in the treatment of subjects with seasonal allergic rhinitis (SAR).

OBJECTIVE

This was a pooled analysis of 2 published studies with identical designs investigating the onset of action of the combination of fexofenadine hydrochloride 60 mg/pseudoephedrine hydrochloride 120 mg (FEX60/PSE120) in subjects with moderate to severe SAR.

METHODS

Subjects aged 12 years received single doses of FEX60/PSE120 or placebo in 2 randomized, double-blind, placebo-controlled, parallel-group, allergen exposure unit studies and recorded their SAR symptoms on diary cards before dosing, at 15-minute intervals for 2 hours after dosing, and at 30-minute intervals for the next 4 hours. The primary efficacy end point was onset of action, assessed in terms of absolute change in the major symptom complex (MSC) score, which was the sum of scores for the individual symptoms of stuffy nose, itchy nose, runny nose, watery eyes, itchy eyes, itchy ears/throat, and sneezing. Secondary end points included the absolute and percent change in the total symptom complex (TSC) score (the sum of the MSC score plus the scores for nose blowing, sniffles, postnasal drip, and cough) and individual symptom scores. Treatment-emergent adverse events (TEAEs) were recorded. Analyses were performed on the modified intention-to-treat (mITT) population, which included all subjects who were randomized to treatment and took the single dose of study medication according to the protocol.

RESULTS

A total of 1693 subjects were screened in the 2 studies, and 786 were randomized (298 in study 1, 488 in study 2). Two subjects withdrew from study 2; therefore, the mITT population consisted of 784 subjects. Subjects' mean age was 33.4 years, and 64.4% were female. The onset of action of FEX60/PSE120 was 45 minutes; the least squares mean (SD) treatment difference in the change from baseline in absolute MSC score was 0.8 (0.31) (95% CI, 0.2-1.4; P = 0.008). All subsequent changes from baseline in MSC scores were statistically significant for FEX60/PSE120 compared with placebo (P < 0.001). The absolute and percent change in TSC score and the percent change in MSC score were significantly decreased at all time points from 45 minutes after dosing for FEX60/PSE120 compared with placebo (all, P < 0.05). Individual symptoms (mean of hours 1 to 5) also were significantly improved with FEX60/PSE120 compared with placebo (all, P < 0.05). TEAEs were reported by 2.3% (9/391) and 4.3% (17/393) of subjects receiving FEX60/PSE120 and placebo, respectively. The most commonly occurring TEAS in the FEX60/PSE120 and placebo groups was somnolence (n = 4 and n = 6, respectively).

CONCLUSION

In this pooled analysis of 2 allergen exposure unit studies, FEX60/PSE120 had an onset of action of 45 minutes and a sustained effect throughout the 6-hour study period in subjects with moderate to severe SAR.

Effects of levocetirizine as add-on therapy to fluticasone in seasonal allergic rhinitis

BACKGROUND

Addition of H(1) antagonists to intranasal corticosteroid treatment of allergic rhinitis (AR) is common in clinical practice and recommended by guidelines, despite some evidence that the additive benefits are negligible.

OBJECTIVE

To assess additional benefits of 5 mg levocetirizine dihydrochloride in seasonal AR patients using 200 mcg fluticasone propionate nasal spray once daily.

METHODS

In a double-blind placebo-controlled crossover study of 27 patients, following 2 weeks without treatment, subjects used fluticasone with levocetirizine or identical placebo for 2 weeks each. Assessments were the Juniper mini Rhinoconjunctivitis Quality-of-Life Questionnaire (mini-RQLQ), domiciliary peak nasal inspiratory flow (PNIF), total nasal symptoms (TNS) scores and nasal nitric oxide concentrations. Effects were interpreted and tested against minimal clinically important differences.

RESULTS

Add-on effects for levocetirizine vs. placebo excluded any clinically significant benefits: mean effects (one sided 95% confidence intervals) were mini-RQLQ -0.11 (-0.34), PNIF +0.57 (+5.23), and TNS -0.11 (-0.60). Numbers needed to treat (95% confidence intervals) by outcome were mini-RQLQ 14 (5 to 49), PNIF 4 (3-7), and TNS 3 (2-6). No significant within or between treatment effects were seen for nasal nitric oxide.

CONCLUSION

Contrary to current practice, the present results demonstrate that for the majority of patients, antihistamine add-on to effective nasal steroid treatment is inappropriate. Further work is required to confirm that this is also true in the most severe cases, and the available evidence needs to be put into guidelines and implemented.

Levocetirizine: a review of its use in the management of allergic rhinitis and skin allergies

Levocetirizine (Xyzal) is a selective, potent, oral histamine H(1) receptor antagonist of the latest generation that is licensed for the symptomatic treatment of allergic rhinitis (including persistent allergic rhinitis [PER]) and chronic idiopathic urticaria (CIU). Large, well designed trials indicate that levocetirizine is effective and generally well tolerated in the treatment of allergic rhinitis and CIU. Its pharmacological profile offers many positive aspects: a rapid onset and long duration of antihistaminic effect; rapid absorption and high bioavailability; a low potential for drug interactions; a low volume of distribution; and a lack of effect on cognition, psychomotor function and the cardiovascular system. Allergen challenge chamber studies suggest that levocetirizine has better efficacy than desloratadine, loratadine or fexofenadine. Well controlled, long-term studies with other later-generation H(1) receptor antagonists are required to fully define its clinical profile relative to other agents in this class. Overall, levocetirizine is a valuable addition to the oral H(1) receptor antagonists available for the treatment of allergic rhinitis and as first-line therapy in patients with CIU.

Pharmacologic and anti-IgE treatment of allergic rhinitis ARIA update (in collaboration with GA2LEN)

The pharmacologic treatment of allergic rhinitis proposed by ARIA is an evidence-based and step-wise approach based on the classification of the symptoms. The ARIA workshop, held in December 1999, published a report in 2001 and new information has subsequently been published. The initial ARIA document lacked some important information on several issues. This document updates the ARIA sections on the pharmacologic and anti-IgE treatments of allergic rhinitis. Literature published between January 2000 and December 2004 has been included. Only a few studies assessing nasal and non-nasal symptoms are presented as these will be discussed in a separate document.

Pathophysiology of nasal obstruction and meta-analysis of early and late effects of levocetirizine

Nasal obstruction, also referred to as congestion, blockage or stuffiness, is a crucial symptom in allergic rhinitis (AR) and may affect sleep as well as quality of life. Early- and late-phase-allergic reactions both contribute to nasal obstruction, although it primarily represents a major symptom in the chronic allergic reaction. A complex network of inflammatory and neurogenic phenomena relates to chronic nasal obstruction, including the subepithelial accumulation of inflammatory cells, particularly mast cells and eosinophils, and the release of neuropeptides. Nasal obstruction is a difficult-to-treat symptom. Vasoconstrictors (decongestants) and intranasal corticosteroids, due to their anti-inflammatory properties, have mainly been used for relieving the nasal passages from the congested mucosa. However, there is accumulating evidence recently that the latest-generation potent antihistamines have decongestant properties in AR. This paper aims to review the pathophysiologic background of nasal obstruction and the evidence for an antihistamine, levocetirizine, in relieving nasal congestion. A meta-analysis on the early and late effects of levocetirizine on nasal obstruction under artificial and natural allergen exposure conditions is presented, demonstrating convincingly that levocetirizine shows a consistent effect on nasal obstruction as early as over the first 2 h and sustained over 6 weeks.

Efficacy of diphenhydramine vs desloratadine and placebo in patients with moderate-to-severe seasonal allergic rhinitis

BACKGROUND

Previous studies have shown that diphenhydramine and desloratadine effectively relieve symptoms of seasonal allergic rhinitis (SAR).

OBJECTIVE

To compare the relative efficacy of 50 mg of diphenhydramine hydrochloride, 5 mg of desloratadine, and placebo in relieving symptoms in patients with moderate-to-severe SAR.

METHODS

In this 1-week, multicenter, parallel-group, randomized, double-blind, double-dummy, placebo-controlled study, 610 patients with moderate-to-severe SAR received 50 mg of diphenhydramine hydrochloride 3 times daily, 5 mg of desloratadine once daily, or placebo. Daily 24-hour reflective total nasal symptom scores (TNSSs) (primary end point), total symptom scores, and individual symptom scores were evaluated. A global evaluation of response to treatment was conducted at 2 posttreatment visits.

RESULTS

The mean reduction from baseline in 24-hour reflective TNSSs relative to the placebo response was 77.6% for the diphenhydramine group (P < .001) and 21.0% for the desloratadine group (P = .12). A TNSS between-treatment difference of -1.81 (46.7%; P < .001) was observed when comparing diphenhydramine with desloratadine. A similar between-treatment difference was observed for the 24-hour reflective total symptom score comparing diphenhydramine to desloratadine (-3.35; 45.5%; P < .001). Diphenhydramine provided clinically and statistically significant reductions vs placebo and desloratadine in all individual symptoms, including nasal congestion. Desloratadine had a tendency toward improvement compared with placebo for most individual symptom scores. However, a statistically significant result was reached only for sneezing (-0.27; 33.9%; P = .04).

CONCLUSIONS

Diphenhydramine, 50 mg, given for 1 week provided statistically significant and clinically superior improvements in symptoms compared with 5 mg of desloratadine in patients with moderate-to-severe SAR. Somnolence occurred more frequently with diphenhydramine (22.1%) compared with desloratadine (4.5%) and placebo (3.4%).

Onset of action of a topical antihistamine as assessed by histamine challenge-induced plasma exudation responses

BACKGROUND

Although usually administered orally, antihistamines are available also for topical use in allergic rhinitis. Information on onset of action of these drugs is incomplete.

OBJECTIVE

To examine onset of action of topical cetirizine-dinitrate on plasma exudation evoked by repeated nasal histamine challenges.

METHODS

A liposome formulation of cetirizine-dinitrate (2.44 mg per nasal cavity) was delivered via a nasal spray device as 2 consecutive actuations per nasal cavity in a placebo-controlled design. The nasal mucosal surface was challenged and lavaged with a histamine solution (100 microg/mL) 5, 15, 25, and 55 minutes after each treatment. In addition, the mucosa was lavaged with saline before each treatment. The lavage fluid levels of alpha2-macroglobulin were measured as an index of mucosal exudation (luminal entry) of plasma.

RESULTS

Histamine produced significant increases in nasal lavage fluid levels of alpha2-macroglobulin at all observation points (5 through 55 minutes after treatment). Nasal cetirizine-dinitrate significantly inhibited this response at 5 and 15 minutes after treatment.

CONCLUSIONS

The effect of topical cetirizine-dinitrate, as established by histamine challenge-induced mucosal exudation of plasma, has an early onset (ie, within 5 to 10 minutes).

Experimental models for the evaluation of treatment of allergic rhinitis

OBJECTIVE

To review the experimental models used for the clinical evaluation of treatments for allergic rhinitis.

DATA SOURCES

Peer-reviewed clinical studies and review articles were selected from the PubMed database using the following relevant keywords: allergic rhinitis in combination with efficacy, wheal and flare, nasal challenge, park, cat room, or exposure unit. Regulatory guidance documents on allergic rhinitis were also included.

STUDY SELECTION

The authors' knowledge of the field was used to limit references with emphasis on recent randomized and controlled studies. References of historical significance were also included.

RESULTS

Traditional outpatient studies are universally accepted in the evaluation of treatment for allergic rhinitis. Experimental models provide ancillary information on efficacy at different stages of treatment development. Skin histamine and allergen challenge, as well as direct nasal challenge with histamine and allergen, are often used as early steps in assessing drug efficacy. Exposure units, park settings, and cat rooms better approximate real life by drawing on the natural mode of allergen exposure and delivering the sensitizing allergen to allergic individuals in the ambient air. Park studies make use of allergens in the outdoors, whereas cat rooms and exposure units present the sensitizing allergens indoors, with the latter providing consistent predetermined allergen levels. Exposure unit and park studies are acknowledged for the determination of onset of action and are also suited to the measurement of duration of effect and other measures of efficacy. Onset and duration of effect are 2 important pharmacodynamic properties of antihistamines and nasal corticosteroids as determined by the Allergic Rhinitis and Its Impact on Asthma and the European Academy of Allergology and Clinical Immunology workshop group.

CONCLUSIONS

All challenge models serve as important instruments in the evaluation of antiallergic medications and provide additional information to complement traditional studies.