Effects of anti-allergic drugs on substance P (SP) and vasoactive intestinal peptide (VIP) in nasal secretions

The SP-TLR axis, which locally primes the nasal mucosa, is impeded in patients with allergic rhinitis

Background

Substance P (SP) and toll‐like receptors (TLRs) contribute to airway disease, particularly during viral infection. We recently demonstrated that SP can act as an initial response to viral stimuli in the upper airway by upregulating TLRs in the nasal epithelia (the SP‐TLR axis). Patients with allergic rhinitis (AR) suffer from prolonged airway infections. The aim of the present study was to examine if patients with AR exhibit a disturbance in the SP‐TLR axis.

Method

Human nasal biopsies and human nasal epithelial cells (HNEC) from healthy volunteers and patients with AR were cultured in the presence of SP. Epithelial expression of TLR4, neutral endopeptidase (NEP) and neurokinin 1 (NK1) were evaluated with flow cytometry and/or quantitative polymerase chain reaction after 30 min to 24 h. The effect of SP on nasal lipopolysaccharide‐induced interleukin‐8 (IL‐8) release was investigated.

Results

SP stimulation of tissue from healthy volunteers resulted in a transient increase of the TLR4 expression, whereas stimulation of AR patient‐derived material led to a delayed and prolonged upregulation of TLR4. NEP expression in HNEC was lower in AR than healthy controls whereas NK1 receptor expression was increased. SP pretreatment increased TLR4‐dependent IL‐8 expression in healthy controls, but not in AR.

Conclusions

SP‐induced regulation of TLR4 in the human nasal mucosa is disturbed in AR. An altered SP‐mediated innate immune response may contribute to the dysfunctional and often prolonged responses to infection in AR.

Effects of azelastine nasal spray on nasal and nasopharyngeal microflora

OBJECTIVE

Azelastine nasal spray is a topical antihistaminic drug for the symptomatic treatment of allergic rhinitis. This study aimed to investigate the effects of azelastine on nasal and nasopharyngeal microflora.

METHODS

Swab samples from 25 patients prescribed azelastine nasal spray monotherapy were collected just before treatment and after 1 month of treatment. After incubation of inoculates, the number of bacteria present in cultures was measured (in colony-forming units per millilitre).

RESULTS

Evaluation of the number of microflora revealed increased bacterial reproduction after treatment, but this difference was not statistically significant. The use of azelastine nasal spray decreased the reproduction of three potentially pathogenic bacteria; however, it did not affect the reproduction of other potentially pathogenic bacteria.

CONCLUSION

The use of azelastine nasal spray for one month did not have a statistically significant effect on the numbers of nasal and nasopharyngeal microflora; it is therefore safe from a microbiological viewpoint.

A clinical pharmacokinetic study comparing two azelastine hydrochloride nasal formulations in a single-dose design

Azelastine hydrochloride is a potent second-generation antihistamine, available in Europe and the USA as a nasal spray formulation for the treatment of allergic rhinitis symptoms. GlaxoSmithKline (GSK) Consumer Healthcare has developed a new nasal formulation of azelastine hydrochloride. The present study was aimed at comparing the clinical pharmacokinetic profiles and assessing the bioequivalence of the new formulation of azelastine hydrochloride with a marketed reference nasal spray product. This was a randomized, two-way crossover, two-stage, single-dose pharmacokinetic study with 2 weeks washout between the two treatment periods. A dosage of 0.28 mg of the test and reference products was administered as a single dose to healthy volunteers according to the crossover design. Twenty-three subjects (15 subjects from stage 1 and 8 subjects from stage 2) were enrolled in the study. Adjusted mean values for AUC0-t were 1,526.8 h pg/mL for the test drug and 1,441.5 h pg/mL for the reference drug; for C max the values were 61.59 pg/mL for the test drug and 58.21 pg/mL for the reference drug. The 94.12 % CI of geometric mean ratios (test/reference) were 0.99-1.13 and 0.95-1.18 for AUC0-t and C max. This met the predefined criteria for bioequivalence between test and reference drugs. Secondary pharmacokinetic parameters for azelastine and for the metabolite desmethyl azelastine, AUC(0-∞) and t max, were numerically similar between the two study treatments. Both test and reference azelastine hydrochloride formulations were well tolerated at single dose. This study demonstrated the bioequivalence between the new azelastine hydrochloride nasal spray formulation and the marketed reference Allergodil(®) after single-dose administration.

Effectiveness of twice daily azelastine nasal spray in patients with seasonal allergic rhinitis

Azelastine nasal spray (Allergodil^®, Lastin^®, Afluon^®; Meda AB, Stockholm, Sweden) is a fast-acting, efficacious and well-tolerated H1-receptor antagonist for the treatment of rhinitis. In addition it also has mast-cell stabilizing and anti-inflammatory properties, reducing the concentration of leukotrienes, kinins and platelet activating factor in vitro and in vivo, as well as inflammatory cell migration in rhinitis patients. Well-controlled studies in patients with seasonal allergic rhinitis (SAR), perennial rhinitis (PR) or vasomotor rhinitis (VMR) confirm that azelastine nasal spray has a rapid onset of action, and improves nasal symptoms associated with rhinitis such as nasal congestion and post-nasal drip. Azelastine nasal spray is effective at the lower dose of 1 spray as well at a dose of 2 sprays per nostril twice daily, but with an improved tolerability profile compared to the 2-spray per nostril twice daily regimen. Compared with intranasal corticosteroids, azelastine nasal spray has a faster onset of action and a better safety profile, showing at least comparable efficacy with fluticasone propionate (Flonase^®; GSK, USA), and a superior efficacy to mometasone furoate (Nasonex^®; Schering Plough, USA). In combination with fluticasone propionate, azelastine nasal spray exhibits greater efficacy than either agent used alone, and this combination may provide benefit for patients with difficult to treat seasonal allergic rhinitis. In addition, azelastine nasal spray can be used on an as-needed basis without compromising clinical efficacy. Compared with oral antihistamines, azelastine nasal spray also demonstrates superior efficacy and a more rapid onset of action, and is effective even in patients who did not respond to previous oral antihistamine therapy. Unlike most oral antihistamines, azelastine nasal spray is effective in alleviating nasal congestion, a particularly bothersome symptom for rhinitis sufferers. Azelastine nasal spray is well tolerated in both adults and children with allergic rhinitis. Bitter taste which seems to be associated with incorrect dosing technique is the most common side effect reported by patients, but this problem can be minimized by correct dosing technique.

Efficacy and safety of azelastine 0.15% nasal spray administered once daily in patients with allergy to Texas mountain cedar pollen

BACKGROUND

A previous study with azelastine nasal spray in patients with seasonal allergic rhinitis (SAR) demonstrated that increasing the azelastine concentration from 0.1% to 0.15% allowed for once-daily dosing without increasing the incidence of adverse effects. This study evaluated the efficacy of azelastine 0.15% nasal spray administered once daily for treating symptoms of SAR.

METHODS

In this 14-day, randomized, double-blind, placebo-controlled study, patients with moderate-to-severe SAR were randomized to azelastine 0.15% (n = 251) or placebo (n = 255), both at a dosage of 2 sprays/nostril once daily. The primary efficacy variable was change from baseline in the 12-hour reflective Total Nasal Symptom Score (TNSS). Key secondary variables were change from baseline in 24-hour instantaneous TNSS, to establish the dosing interval, and change from baseline in the Total Ocular Symptom Score (TOSS).

RESULTS

The mean improvement (3.57) and percentage improvement (19.3%) in 12-hour reflective TNSS was significant (p < 0.012) with azelastine 0.15% compared to placebo (2.14 and 11.4%, respectively). The mean improvement in 24-hour instantaneous TNSS was also significant (p < 0.001) for azelastine 0.15% compared to placebo, indicating efficacy with once-daily dosing. The overall improvement and percentage improvement in TOSS was significant (p ≤ 0.012) with azelastine 0.15% (2.21 and 16.7%, respectively) compared to placebo (1.28 and 6.0%, respectively). The overall score for the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) was significantly (p < 0.001) improved from baseline in the azelastine group compared with the placebo group. Nasal discomfort (3.6%) and bitter taste (2.4%) were the most common adverse events. There were no reports of somnolence with azelastine.

CONCLUSION

Azelastine 0.15% was effective and well tolerated with once-daily dosing. Azelastine 0.15% nasal spray significantly improved a complex of eye symptoms compared to placebo.

Effects on neuroendocrinoimmune network of Lizhong Pill in the reserpine induced rats with spleen deficiency in traditional Chinese medicine

AIM OF THE STUDY

Lizhong Pill, composed of radix Ginseng (Panax ginseng C.A. Meyer), rhizoma Zingiberis (Zingiber officinale Roscoe), rhizoma Atractylodis Macrocephalae (Atractylodes macrocephala Koidz.) and radix Glycytthizae (Glycyrrhiza uralensis Fisch.), is a classical herbal product for curing spleen deficiency in traditional Chinese medicine (TCM), and reserpine treated rats show similar signs to TCM spleen deficiency pattern. This paper is aimed to explore the regulatory effect on neuroendocrinoimmune network by Lizhong Pill in reserpine induced TCM spleen deficiency rats.

MATERIALS AND METHODS

100 healthy adult male SD rats, with a mean weight of 200 g, were randomly divided into five groups in average: control group, reserpine treated group, atropine treated group, treatment groups with Lizhong Pill at high dose and low dose (equal to the dosage of crude drugs for 4 g/kg/d and 8 g/kg/d). Rats in reserpine treated group were induced by intraperitoneal injection of reserpine at 0.5 mg/kgd for 4 weeks. The levels of IL-1, IL-6 and gastrin were measured with radioimmunoassay, TNF-α and IFN-γ in serum were measured with ELISA, the level of vasoactive intestinal peptide (VIP) and substance P (SP) in small intestine were determined with radioimmunoassay, and the TNF-α and TGF-β positive cells in small intestine were detected by immunohistological staining. Data were analyzed with SAS 9.1 software package.

RESULTS

The rats in reserpine treated group, body weight, concentrations of IFN-γ, IL-1 and TNF-α in serum, expression of TGF-β in small intestine, VIP in small intestine decreased (P<0.05), and the level of IL-6 in serum, expression of TNF-α, SP in small intestine and gastrin were increased (P<0.05). Administration of Lizhong Pill at high dose could increase the body weights at day 21, and the weights of rats in Lizhong Pill groups were much higher compared to reserpine treated group. At high dose of Lizhong Pill could increase the level of TNF-α in serum. Lizhong Pill at high dose and low dose could reverse the changes of IL-1, IL-6 and IFN-γ, gastrin, expression of TGF-β and TNF-α, VIP and SP in small intestine.

CONCLUSIONS

The rats treated with reserpine, with similar signs to TCM spleen deficiency, show neuroendocrinoimmune disorders, and the restoration of the neuroendocrinoimmune disorders might be the part of mechanism of Lizhong Pill for reinforcing TCM spleen deficiency.

Double-Blind, Placebo-Controlled Trial of Reformulated Azelastine Nasal Spray in Patients with Seasonal Allergic Rhinitis

Background

Azelastine nasal spray is a topical antihistamine with a distinctive taste that may be objectionable to some patients. The primary objectives of this clinical trial were (1) to determine if a reformulated azelastine nasal spray (Astepro) with sucralose as a taste-masking agent provides comparable efficacy to the original formulation (Astelin) and (2) to evaluate dose–response relationships between groups.

Methods

Eight hundred thirty-five patients with seasonal allergic rhinitis were randomized to six treatment groups: (1) original azelastine nasal spray, 1 spray/nostril b.i.d.; (2) reformulated azelastine, 1 spray/nostril b.i.d.; (3) placebo, 1 spray/nostril b.i.d.; (4) original azelastine nasal spray, 2 sprays/nostril b.i.d., (5) reformulated, 2 sprays/nostril b.i.d.; and (6) placebo, 2 sprays/nostril b.i.d. The primary efficacy variable was the change from baseline to day 14 in total nasal symptom score (TNSS) consisting of runny nose, sneezing, itchy nose, and nasal congestion.

Results

Original azelastine nasal spray and the reformulated spray produced comparable improvements in the TNSS at both dosages. There was a dose-related difference in TNSS comparing the 1- and 2-spray dosages. The percentage changes from baseline in the TNSS in the 2-sprays/nostril dosage groups were 27.9% (p < 0.001) with the reformulated nasal spray, 23.5% (p < 0.01) with the original formulation, and 15.4% with placebo. The incidence of bitter taste was 7% with the reformulated spray and 8% with the original at the 2-sprays/nostril dosage.

Conclusion

The results of this study showed efficacy both with original azelastine nasal spray and with the reformulated nasal spray and a clear dose–response difference between the 1- and 2-spray dosages.

Impact of azelastine nasal spray on symptoms and quality of life compared with cetirizine oral tablets in patients with seasonal allergic rhinitis

BACKGROUND

In fall 2004, the first Azelastine Cetirizine Trial demonstrated statistically significant improvements in the total nasal symptom score (TNSS) and Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores with the use of azelastine nasal spray vs oral cetirizine in patients with seasonal allergic rhinitis (SAR).

OBJECTIVE

To compare the effects of azelastine nasal spray vs cetirizine on the TNSS and RQLQ scores in patients with SAR.

METHODS

This 2-week, double-blind, multicenter trial randomized 360 patients with moderate-to-severe SAR to azelastine, 2 sprays per nostril twice daily, or cetirizine, 10-mg tablets once daily. The primary efficacy variable was the 12-hour reflective TNSS (rhinorrhea, sneezing, itchy nose, and nasal congestion). Secondary efficacy variables were individual symptom scores and the RQLQ score.

RESULTS

Azelastine nasal spray and cetirizine significantly improved the TNSS and individual symptoms compared with baseline (P < .001). The TNSS improved by a mean of 4.6 (23.9%) with azelastine nasal spray compared with 3.9 (19.6%) with cetirizine. Significant differences favoring azelastine nasal spray were seen for the individual symptoms of sneezing and nasal congestion. Improvements in the RQLQ overall (P = .002) and individual domain (P < or = .02) scores were greater with azelastine nasal spray. Both treatments were well tolerated.

CONCLUSIONS

Azelastine nasal spray and cetirizine effectively treated nasal symptoms in patients with SAR. Improvements in the TNSS and individual symptoms favored azelastine over cetirizine, with significant differences for nasal congestion and sneezing. Azelastine nasal spray significantly improved the RQLQ overall and domain scores compared with cetirizine.

Allergic rhinitis: impact of the disease and considerations for management

AR is a common condition affecting individuals of all ages. Those afflicted with AR often suffer from associated inflammatory conditions of the mucosa,such as AC, rhinosinusitis, asthma, otitis media with effusion, and other atopic conditions, such as eczema and food allergies. Lack of treatment or treatment with suboptimal therapy may result in reduced quality of life and compromise productivity at work or school. Although environmental controls may prove difficult to implement, and not all controls appear adequately to mitigate symptoms of AR, they continue to represent a foundation for treatment. Many different classes of medications are now available, and they have been shown to be effective and safe in a large number of well-designed, double-blind, placebo-controlled clinical trials. Some of the over-the-counter medi-cations have been associated with increased sedation, potentially leading to accidents and fatalities at work or while operating complex machinery, such as automobiles. Only immunotherapy with increasing doses of individually targeted allergens results in sustained changes in the immune system. Although anti-IgE is probably only the first successful immunomodulator commercially available to treat AR, monoclonal antibodies will remain too costly, at least in the near future, to find their way into routine AR treatment.

Effectiveness of azelastine nasal spray compared with oral cetirizine in patients with seasonal allergic rhinitis

BACKGROUND

Azelastine nasal spray and oral cetirizine are selective histamine H(1)-receptor antagonists that are approved in the United States for the treatment of seasonal allergic rhinitis (SAR).

OBJECTIVE

The objective of the present study was to compare the efficacy and tolerability of azelastine nasal spray administered at the recommended dosage of 2 sprays per nostril twice daily with those of cetirizine in the treatment of moderate to severe SAR.

METHODS

This multicenter, randomized, double-blind, parallel-group, 2-week comparative study was conducted during the 2004 fall allergy season in patients with moderate to severe SAR. After a 1-week placebo lead-in period, patients were randomized to receive azelastine nasal spray 2 sprays per nostril twice daily plus placebo tablets or cetirizine 10-mg tablets once daily plus a placebo saline nasal spray for the 2-week double-blind treatment period. The primary efficacy variables were (1) change from baseline to day 14 in the 12-hour reflective total nasal symptom score (TNSS), which combines scores for rhinorrhea, sneezing, itchy nose, and nasal congestion, and (2) onset of action, based on the instantaneous TNSS over 4 hours after the first dose of study drug. During the double-blind treatment period, patients recorded their symptom scores on diary cards twice daily (morning and evening). Patients aged > or =18 years also completed the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) at baseline and on day 14.

RESULTS

Three hundred seven patients were randomized to treatment, and 299 completed 2 weeks of study treatment. The age of the population ranged from 12 to 74 years (mean, 35 years), 62.9% were female, and 69.6% were white. Over 2 weeks of treatment, both groups had significant improvements in the TNSS compared with baseline (P < 0.001). The overall change in TNSS was significantly greater with azelastine nasal spray compared with cetirizine (29.3% vs 23.0% improvement, respectively; P = 0.015). In terms of onset of action, azelastine nasal spray significantly improved the instantaneous TNSS compared with cetirizine at 60 and 240 minutes after the initial dose (both, P = 0.040). Scores on each domain of the RQLQ were significantly improved in both groups compared with baseline (P < 0.001); the overall RQLQ score was significantly improved with azelastine nasal spray compared with cetirizine (P = 0.049). Both treatments were well tolerated.

CONCLUSION

In this 2-week study in patients with moderate to severe SAR, azelastine nasal spray was well tolerated and produced significantly greater improvements in TNSS and total RQLQ score compared with cetirizine.

Identification of human P450 isoforms involved in the metabolism of the antiallergic drug, oxatomide, and its kinetic parameters and inhibition constants

Oxatomide is an antiallergic drug used for the treatment of diseases mediated by type I allergy. Recently, terfenadine and astemizole, which have antiallergic actions similar to those of oxatomide, showed side effects on the cardiovascular system. This might be because concomitant drugs such as itraconazole inhibit cytochrome P450 3A4 (CYP3A4), the enzyme responsible for the degradation of terfenadine and astemizole, and thus the blood concentrations of the drugs are abnormally increased. In another article of this issue, we have reported that oxatomide is metabolized by CYP2D6-Val and CYP3A4, and simultaneously inhibits the metabolism of the model substrates for these enzymes. In this study, we performed the kinetic analysis of oxatomide metabolism using microsomes prepared from human liver, and found that the Km and Vmax values were 26.1 microM and 1254.4 pmol/mg protein/min, respectively. Ketoconazole, one of the representative inhibitors for CYP3A4, potently inhibited the metabolism of oxatomide, but other well-known CYP inhibitors did not show significant inhibition. These results suggest that the metabolism of oxatomide is principally catalyzed by CYP3A4. Furthermore, oxatomide inhibited the metabolism of (+/-) bufuralol and testosterone, model substrates for CYP2D6 and CYP3A4, respectively, in a dose-dependent manner with the Ki values of 57.4 and 24.3 microM, respectively. These observations, together with the finding that the putative highest concentration of oxatomide in blood was congruent with 40 ng/ml ( congruent with 93 nM) at 4 h after each dosage during consecutive 6-d administration, encouraged us to conclude that oxatomide won't inhibit CYP2D6 or CYP3A4 at clinical doses.

Identification of human p450 isoforms involved in the metabolism of the antiallergic drug, oxatomide, and its inhibitory effect on enzyme activity

Oxatomide is an antiallergic drug used for the treatment of diseases mediated by type I allergy. Recently, it has been reported that terfenadine and astemizole, which have antiallergic actions similar to those of oxatomide, show side effects on the cardiovascular system, such as QT prolongation, ventricular arrhythmia and cardiac arrest. This might be because concomitant drugs such as itraconazole inhibit cytochrome P450 3A4 (CYP3A4), the enzyme responsible for degradation of terfenadine and astemizole, and thus the blood concentrations of the drugs are abnormally increased. On the other hand, isoforms of P450 involved in the metabolism of oxatomide have not been clarified. Therefore, we attempted to identify these isoforms using microsome preparations of in vitro expression systems derived from a human lymphoblastoid cell line. Oxatomide was metabolized by CYP2D6-Val and CYP3A4, but not by CYP1A2, CYP2C9-Arg, CYP2C9-Cys or CYP2C19. We also examined whether oxatomide showed inhibitory effects on metabolic activity of individual P450 isozymes using model substrates for each isozyme. Oxatomide did not inhibit the metabolism of the model substrates for CYP1A2, CYP2C9-Arg, CYP2C9-Cys and CYP2C19, but inhibited the degradation of those for CYP2D6-Val and CYP3A4. It was found that oxatomide is metabolized by CYP2D6 and CYP3A4 in human liver microsomes, and simultaneously acts as an inhibitor for these isoforms, responsible for the metabolism of the drug itself.

Neuronal Plasticity in Persistent Perennial Allergic Rhinitis

OBJECTIVE

Persistent perennial allergic rhinitis belongs to the most frequent diseases in occupational and environmental medicine. Because the innervation may play a role in the pathogenesis of the disease, the present study analyzed nasal mucosal nerve profiles.

METHODS

Neuropeptide-containing nerve fibers were examined using immunohistochemistry and related to eosinophil and mast cell numbers.

RESULTS

In contrast to constant numbers of mast cells, there was a significant increase in the number of eosinophils. Immunohistochemistry for calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal peptide (VIP), and neuropeptide tyrosine (NPY) revealed abundant staining of mucosal nerves. Semiquantitative assessment of nerve fiber neuropeptide density demonstrated a significant increase of VIP-positive fibers in rhinitis tissues.

CONCLUSIONS

The present data indicate a differential regulation of neuropeptide-containing nerve fibers with increased numbers of VIPergic fibers suggesting a modulatory role of the upper airway innervation in perennial allergic rhinitis.

Efficacy of azelastine nasal spray in seasonal allergic rhinitis patients who remain symptomatic after treatment with fexofenadine

BACKGROUND

Currently available oral second-generation antihistamines do not provide adequate symptom relief for many allergy patients.

OBJECTIVE

To determine the ability of azelastine nasal spray to improve rhinitis symptoms in patients with seasonal allergic rhinitis who remained symptomatic after treatment with fexofenadine.

METHODS

This was a multicenter, randomized, double-blind, placebo-controlled, 2-week study in patients with moderate-to-severe seasonal allergic rhinitis. The study began with a 1-week, open-label lead-in period, during which patients received fexofenadine, 60 mg twice daily. Patients who improved less than 25% to 33% with fexofenadine were randomized to treatment with (1) azelastine nasal spray, 2 sprays per nostril twice daily; (2) azelastine nasal spray, 2 sprays per nostril twice daily, plus fexofenadine, 60 mg twice daily; or (3) placebo (saline) nasal spray and placebo capsules twice daily. The primary efficacy variable was the change from baseline to day 14 in the total nasal symptom score (TNSS), consisting of runny nose, sneezing, itchy nose, and nasal congestion symptom scores.

RESULTS

A total of 334 patients who remained symptomatic after treatment with fexofenadine were included in the efficacy analysis. After 2 weeks of treatment, azelastine nasal spray (P = .007) and azelastine nasal spray plus fexofenadine (P = .003) significantly improved the TNSS compared with placebo. Azelastine nasal spray monotherapy was as effective as the combination of azelastine nasal spray plus fexofenadine as measured by the TNSS and individual symptoms of the TNSS.

CONCLUSIONS

Azelastine nasal spray is effective monotherapy for patients who remain symptomatic after treatment with fexofenadine and should be considered in the initial management of patients with seasonal allergic rhinitis.

Treatment of nonallergic perennial rhinitis

Nonallergic perennial rhinitis (also commonly referred to as vasomotor rhinitis) is a chronic non-IgE-mediated condition that is characterized by symptoms which are similar to those seen in allergic rhinitis, but which persist for over nine months each year. Although treatment of vasomotor rhinitis involves the use of either intranasal corticosteroids or antihistamines, the corticosteroids are generally not effective in treatment of all the symptoms of vasomotor rhinitis and have generally been shown to be effective in patients with eosinophilia. With the exception of azelastine, the only topical antihistamine to be approved by the FDA for the treatment of nonallergic rhinitis, the antihistamines have also produced inconsistent results. While clinical studies of azelastine have demonstrated that this drug is highly efficacious in the treatment of all the symptoms of vasomotor rhinitis, mechanistic studies have demonstrated that azelastine has potent anti-inflammatory effects (in particular attenuation of the expression and synthesis of pro-inflammatory cytokines, leukotrienes, and cell adhesion molecules), which are likely to contribute to its clinical efficacy. Furthermore, pharamacokinetic studies have suggested that since azelastine has a more rapid onset of action, compared to most other antihistamines and intranasal corticosteroids, then azelastine nasal spray may be considered as primary therapy for patients with symptoms of both allergic and/or vasomotor (nonallergic perennial) rhinitis.

Efficacy of azelastine nasal spray in patients with an unsatisfactory response to loratadine

OBJECTIVE

To evaluate the effectiveness and safety of azelastine nasal spray, desloratadine, and the combination of azelastine nasal spray plus loratadine compared with placebo in patients with seasonal allergic rhinitis who had an unsatisfactory response to loratadine.

METHODS

This was a 2-week, multicenter, placebo-controlled, randomized, double-blind study in patients with moderate-to-severe symptoms of seasonal allergic rhinitis. Following a 1-week, open-label lead-in period, during which the patients received loratadine 10 mg daily, those patients who met the symptom qualification criteria (<25% to 33% improvement taking loratadine) were randomized to treatment with azelastine nasal spray 2 sprays per nostril, twice daily, azelastine nasal spray 2 sprays per nostril, twice daily, plus loratadine 10 mg daily, desloratadine 5 mg daily plus placebo (saline) nasal spray, or placebo (saline) nasal spray/placebo capsules. The primary efficacy variable was the change from baseline to day 14 in the total nasal symptom score, consisting of runny nose, sneezing, itchy nose, and nasal congestion symptom scores recorded twice daily (AM and PM) in patient diary cards.

RESULTS

A total of 428 patients with an unsatisfactory response to loratadine completed the double-blind treatment period. After 2 weeks of treatment, azelastine nasal spray (P < 0.001), azelastine nasal spray plus loratadine (P < 0.001), and desloratadine (P = 0.039) significantly improved the total nasal symptom score compared with placebo.

CONCLUSIONS

Azelastine nasal spray is an effective treatment for patients with seasonal allergic rhinitis who do not respond to loratadine and is an alternative to switching to another oral antihistamine or to using multiple antihistamines.

New insights into the second generation antihistamines

Second generation antihistamines are recognised as being highly effective treatments for allergy-based disease and are among the most frequently prescribed and safest drugs in the world. However, consideration of the therapeutic index or the benefit/risk ratio of the H1 receptor antagonists is of paramount importance when prescribing this class of compounds as they are used to treat non-life threatening conditions. There are many second generation antihistamines available and at first examination these appear to be comparable in terms of safety and efficacy. However, the newer antihistamines in fact represent a heterogeneous group of compounds, having markedly differing chemical structures, adverse effects, half-life, tissue distribution and metabolism, spectrum of antihistaminic properties, and varying degrees of anti-inflammatory effects. With regard to the latter, there is growing awareness that some of these compounds might represent useful adjunct medications in asthma therapy. In terms of safety issues, the current second generation grouping includes compounds with proven cardiotoxic effects and others with the potential for adverse drug interactions. Moreover, some of the second generation H1 antagonists have given cause for concern regarding their potential to cause a degree of somnolence in some individuals. It can be argued, therefore, that the present second generation grouping is too large and indistinct since this was based primarily on the concept of separating the first generation sedating compounds from nonsedating H1 antagonists. Although it is too early to talk about a third generation grouping of antihistamines, future membership of such a classification could be based on a low volume of distribution coupled with a lack of sedating effects, drug interactions and cardiotoxicity.

Update on nonallergic rhinitis

BACKGROUND

Although nonallergic rhinitis is a well recognized entity, its incidence and therapy have not been definitively studied. Recent epidemiologic studies and treatment trials have furthered our knowledge regarding the frequency of occurrence of this disorder and effective treatment modalities.

OBJECTIVE

To review and put into perspective recent advances in our knowledge regarding the incidence and significance as well as therapy of chronic nonallergic rhinitis. In addition, based upon these data, to propose a classification of this disorder.

DATA SOURCES

The MEDLINE database and the results of a national survey of allergists (National Rhinitis Task Force) conducted in 15 allergy practices involving 975 patients.

CONCLUSIONS

Nonallergic rhinitis is a common disease that probably affects as many as 17 million Americans. Of equal importance is that, based on available data, approximately 22 million people suffer with a combination of nonallergic rhinitis and allergic diseases (mixed rhinitis). Both nonallergic and mixed rhinitis occur more frequently in adults than in children, may be more common in female patients than in male patients, and are more likely to be perennial than seasonal. Agents demonstrating efficacy (based on controlled trials or having approval by the FDA) for the therapy of nonallergic rhinitis are azelastine and topical nasal steroids.

Efficacy of azelastine nasal spray in the treatment of vasomotor (perennial nonallergic) rhinitis

BACKGROUND

Azelastine hydrochloride is an antihistamine with anti-inflammatory properties that is available in the United States in a nasal spray formulation for the treatment of seasonal allergic rhinitis. Vasomotor (perennial nonallergic) rhinitis (VMR) is a noninfectious, chronic rhinitis usually not associated with inflammatory cell infiltration.

OBJECTIVE

Two multicenter, randomized, double-blind, placebo-controlled, parallel-group clinical trials were conducted to determine whether patients with symptoms of VMR (rhinorrhea, sneezing, postnasal drip, and nasal congestion) could be effectively treated with azelastine nasal spray.

METHODS

All of the patients who participated in the trials had a diagnosis of VMR, symptoms for at least 1 year, negative skin tests for a mixed panel of seasonal and perennial allergens, and a nasal cytology examination negative for eosinophils. After a 1-week, single-blind, placebo lead-in period, patients who met the symptom severity qualification criteria were randomized to receive either azelastine nasal spray (two sprays per nostril twice daily, 1.1 mg/day) or placebo nasal spray for 21 days. Patients recorded the severity of their VMR symptoms on diary cards each morning and evening of the trial using a four-point symptom rating scale (0 = none to 3 = severe). The primary efficacy variable was the overall reduction from baseline in the total vasomotor rhinitis symptom score (TVRSS) over the 21-day, double-blind treatment period.

RESULTS

In both studies, azelastine nasal spray significantly (study 1, P = .002; study 2, P = .005) reduced the TVRSS from baseline when compared with placebo. Significant improvement was observed within the first week and improvement in all symptoms favored treatment with azelastine nasal spray. No serious or unexpected adverse events were reported in either study. Bitter taste (19% vs 2%) was the only adverse experience that occurred with a statistically significantly greater incidence in the azelastine group than in the placebo group.

CONCLUSIONS

This is the first demonstration of the efficacy of an antihistamine in the therapy of VMR in two double-blind, placebo-controlled clinical trials.