A double-blinded, comparative study of the effects of short preseason specific immunotherapy and topical steroids in patients with allergic rhinoconjunctivitis and asthma

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Pharmacology, particle deposition and drug administration techniques of intranasal corticosteroids for treating allergic rhinitis

This review presents an overview of the available literature regarding intranasal corticosteroids (INCs) for the treatment of allergic rhinitis (AR). Various treatment options exist for AR including INCs, antihistamines and leucotriene antagonists. INCs are considered to be the most effective therapy for moderate-to-severe AR, as they are effective against nasal and ocular symptoms and improve quality of life. Their safety has been widely observed. INCs are effective and safe for short-term use. Local adverse events are observed but generally well-tolerated. The occurrence of (serious) systemic adverse events is unlikely but cannot be ruled out. There is a lack of long-term safety data. INC may cause serious eye complications. The risk of INCs on the hypothalamic-pituitary-adrenal axis, on bone mineral density reduction or osteoporosis and on growth in children, should be considered during treatment. Pharmacological characteristics of INCs (e.g. the mode of action and pharmacokinetics) are well known and described. We sought to gain insight into whether specific properties affect the efficacy and safety of INCs, including nasal particle deposition, which the administration technique affects. However, advances are lacking regarding the improved understanding of the effect of particle deposition on efficacy and safety and the effect of the administration technique. This review emphasizes the gaps in knowledge regarding this subject. Advances in research and health care are necessary to improve care for patients with AR.

Subcutaneous allergen immunotherapy in the treatment of allergic respiratory disease

Subcutaneous immunotherapy is recognized as a cornerstone in the management of allergic respiratory disease in patients who are properly characterized with allergy and with allergic rhinoconjunctivis and/or well-controlled asthma, and who are willing to adhere to the rigorous treatment program. A key tenet is that it affords the opportunity to effect long-term clinical remission through its disease-modifying properties. Furthermore, it has the potential to prevent the progression of allergic rhinitis to asthma, prevent new allergen sensitivities, and improve a patient's quality of life.

Allergen-specific immunotherapy induces regulatory T cells in an atopic dermatitis mouse model

BACKGROUND

Several studies have demonstrated that allergen-specific immunotherapy (SIT) can be an effective treatment for atopic dermatitis (AD). However, there is no relevant mouse model to investigate the mechanism and validate the novel modality of SIT in AD.

METHODS

NC/Nga mice with induced AD-like skin lesions received a subcutaneous injection of SIT (an extract of the house dust mite Dermatophagoides farinae [DfE]) or placebo for 5 weeks). Clinical and histological improvements of AD-like skin lesions were examined. The responses of local and systemic regulatory T (Treg) cells, natural killer (NK) cells, B cells, serum immunoglobulin, and T-cell cytokine response to DfE were evaluated to determine the underlying mechanism of the observed results.

RESULTS

Specific immunotherapy significantly improved AD-like skin lesions. Histologically, SIT decreased epidermal thickness and reduced inflammatory cell infiltration, especially that of eosinophils. Concomitantly, SIT suppressed Th2 responses and induced local infiltration of Treg cells into the skin. Also, SIT induced the immunoglobulin G4 and attenuated allergen-specific immunoglobulin E. Furthermore, SIT induced local and systemic IL-10-producing Treg cells and regulatory NK cells.

CONCLUSION

We established a SIT model on AD mice and showed that our model correlates well with previous reports about SIT-treated patients. Also, we revealed NK cells as another possible resource of IL-10 in SIT. Based on our results, we suggest our SIT model as a useful tool to investigate mechanism of action of SIT and to validate the efficacy of new SIT modalities for the treatment of AD.

New approaches to allergen immunotherapy

OBJECTIVE

New insights into mechanisms should enable strategic improvement of allergen immunotherapy, aiming to make it safer, faster, more effective, and able to induce long-term tolerance. We review novel approaches with potential to translate into clinical use.

DATA SOURCES

Database searches were conducted in PubMed, Scopus, and Google Scholar.

STUDY SELECTIONS

Search terms were based on current and novel approaches in immunotherapy. Literature was selected primarily from recent randomized double-blinded placebo-controlled trials and meta-analyses.

RESULTS

Alum, microcrystalline tyrosine, and calcium phosphate are adjuvants in current use. Toll-like receptor-4 agonists combined with allergen have potential to shorten duration of treatment. Other novel adjuvants, nanoparticles, and virus-like particles in combination with allergen have shown early promise. Omalizumab lessens systemic side effects but does not improve efficacy. Intralymphatic immunotherapy for aeroallergens, epicutaneous immunotherapy for food allergens, and use of modified allergens (allergoids), recombinant allergens (and hypoallergenic variants), and T- and B-cell peptide approaches have shown evidence of efficacy and permitted shortened courses but have only rarely been compared with conventional extracts.

CONCLUSION

Novel routes of immunotherapy, use of modified allergens, and combination of allergens with immunostimulatory adjuvants or immune modifiers have been developed to augment downregulation of T-helper cell type 2 immunity and/or induce "protective" blocking antibodies. Although these strategies have permitted shortened courses, confirmatory phase 3 trials are required to confirm efficacy and safety and head-to-head trials are required for comparative efficacy. Currently, subcutaneous and sublingual immunotherapies using in-house standardized crude extracts remain the only approaches proved to induce long-term tolerance.

Allergen immunotherapy for allergic asthma: A systematic review and meta-analysis

BACKGROUND

To inform the development of the European Academy of Allergy and Clinical Immunology's (EAACI) Guidelines on Allergen Immunotherapy (AIT) for allergic asthma, we assessed the evidence on the effectiveness, cost-effectiveness and safety of AIT.

METHODS

We performed a systematic review, which involved searching nine databases. Studies were screened against predefined eligibility criteria and critically appraised using established instruments. Data were synthesized using random-effects meta-analyses.

RESULTS

98 studies satisfied the inclusion criteria. Short-term symptom scores were reduced with a standardized mean difference (SMD) of -1.11 (95% CI -1.66, -0.56). This was robust to a prespecified sensitivity analyses, but there was evidence suggestive of publication bias. Short-term medication scores were reduced SMD -1.21 (95% CI -1.87, -0.54), again with evidence of potential publication bias. There was no reduction in short-term combined medication and symptom scores SMD 0.17 (95% CI -0.23, 0.58), but one study showed a beneficial long-term effect. For secondary outcomes, subcutaneous immunotherapy (SCIT) improved quality of life and decreased allergen-specific airway hyperreactivity (AHR), but this was not the case for sublingual immunotherapy (SLIT). There were no consistent effects on asthma control, exacerbations, lung function, and nonspecific AHR. AIT resulted in a modest increased risk of adverse events (AEs). Although relatively uncommon, systemic AEs were more frequent with SCIT; however no fatalities were reported. The limited evidence on cost-effectiveness was mainly available for sublingual immunotherapy (SLIT) and this suggested that SLIT is likely to be cost-effective.

CONCLUSIONS

AIT can achieve substantial reductions in short-term symptom and medication scores in allergic asthma. It was however associated with a modest increased risk of systemic and local AEs. More data are needed in relation to secondary outcomes, longer-term effectiveness and cost-effectiveness.

Allergen immunotherapy for allergic rhinoconjunctivitis: A systematic review and meta-analysis

BACKGROUND

The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis. To inform the development of clinical recommendations, we undertook a systematic review to assess the effectiveness, cost-effectiveness, and safety of AIT in the management of allergic rhinoconjunctivitis.

METHODS

We searched nine international biomedical databases for published, in-progress, and unpublished evidence. Studies were independently screened by two reviewers against predefined eligibility criteria and critically appraised using established instruments. Our primary outcomes of interest were symptom, medication, and combined symptom and medication scores. Secondary outcomes of interest included cost-effectiveness and safety. Data were descriptively summarized and then quantitatively synthesized using random-effects meta-analyses.

RESULTS

We identified 5960 studies of which 160 studies satisfied our eligibility criteria. There was a substantial body of evidence demonstrating significant reductions in standardized mean differences (SMD) of symptom (SMD -0.53, 95% CI -0.63, -0.42), medication (SMD -0.37, 95% CI -0.49, -0.26), and combined symptom and medication (SMD -0.49, 95% CI -0.69, -0.30) scores while on treatment that were robust to prespecified sensitivity analyses. There was in comparison a more modest body of evidence on effectiveness post-discontinuation of AIT, suggesting a benefit in relation to symptom scores.

CONCLUSIONS

AIT is effective in improving symptom, medication, and combined symptom and medication scores in patients with allergic rhinoconjunctivitis while on treatment, and there is some evidence suggesting that these benefits are maintained in relation to symptom scores after discontinuation of therapy.

Allergen immunotherapy for allergic asthma: a systematic overview of systematic reviews

Background

There is clinical uncertainty about the effectiveness and safety of allergen immunotherapy (AIT) for the treatment of allergic asthma.

Objectives

To undertake a systematic overview of the effectiveness, cost-effectiveness and safety of AIT for the treatment of allergic asthma.

Methods

We searched nine electronic databases from inception to October 31, 2015. Systematic reviews were independently screened by two reviewers against pre-defined eligibility criteria and critically appraised using the Critical Appraisal Skills Programme quality assessment tool for systematic reviews. Data were descriptively and thematically synthesized.

Results

We identified nine eligible systematic reviews; these focused on delivery of AIT through the following routes: subcutaneous (SCIT; n = 3); sublingual (SLIT; n = 4); and both SCIT and SLIT (n = 2). This evidence found that AIT delivered by SCIT and SLIT can improve medication and symptom scores and measures of bronchial hyper-reactivity. The impact on measures of lung function or asthma control was however less clear. We found no systematic review level evidence on the cost-effectiveness of SCIT or SLIT. SLIT had a favorable safety profile when compared to SCIT, particularly in relation to the risk of systemic reactions.

Conclusions

AIT has the potential to achieve reductions in symptom and medication scores, but there is no clear or consistent evidence that measures of lung function can be improved. Bearing in mind the limitations of synthesizing evidence from systematic reviews and the fact that these reviews include mainly dated studies, a systematic review of current primary studies is now needed to update this evidence base, estimate the effectiveness of AIT on asthma outcomes and to investigate the relative effectiveness, cost-effectiveness and safety of SCIT and SLIT.

Treatment effect of sublingual immunotherapy tablets and pharmacotherapies for seasonal and perennial allergic rhinitis: Pooled analyses

BACKGROUND

Data comparing the treatment effect of allergy immunotherapy and pharmacotherapy are lacking.

OBJECTIVE

We sought to indirectly compare the treatment effect of sublingual immunotherapy (SLIT)-tablets with pharmacotherapy for seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR).

METHODS

Pooled data from randomized, double-blind, placebo-controlled trials for the clinical development programs of selected allergic rhinitis treatments were evaluated. Total nasal symptom scores (TNSSs) relative to placebo were compared. Subjects scored symptoms daily during entire pollen seasons in 6 timothy grass SLIT-tablet trials (n = 3094) and 2 ragweed SLIT-tablet trials (n = 658) and during the last 8 weeks of treatment in 2 house dust mite (HDM) SLIT-tablet trials (n = 1768). Subjects scored symptoms daily in 7 montelukast (10 mg, n = 6799), 9 desloratadine (5 mg, n = 4455), and 8 mometasone furoate nasal spray (MFNS; 200 μg daily, n = 2140) SAR or PAR trials. SLIT-tablet trials allowed rescue medication use, whereas most pharmacotherapy trials did not. A fixed-effect meta-analysis method estimated differences in on-treatment average TNSSs.

RESULTS

In grass and ragweed SLIT-tablet trials, overall improvement in TNSSs relative to placebo was 16.3% and 17.1%, respectively. In HDM SLIT-tablet trials, TNSS overall improvement relative to placebo was 16.1%. In the montelukast, desloratadine, and MFNS trials, TNSS overall improvement relative to placebo was 5.4%, 8.5%, and 22.2%, respectively, for SAR trials, and 3.7%, 4.8%, and 11.2%, respectively, for PAR trials.

CONCLUSIONS

Although comparisons were limited by study design heterogeneity and use of rescue medications in SLIT-tablet trials, effects on nasal symptoms with timothy grass and ragweed SLIT-tablets were nearly as great as with MFNS and numerically greater than with montelukast and desloratadine for SAR. HDM SLIT-tablet effects were numerically greater than all pharmacotherapies for PAR. SLIT-tablets offer the additional benefit of long-term efficacy.

Optimal Duration of Allergic Rhinitis Clinical Trials

OBJECTIVE: Guidelines have been published by the Food and Drug Administration (FDA) and the European Agency for the Evaluation of Medicinal Products (EMEA) for the conduct of seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR) studies. These guidelines have differences regarding the duration of such trials: the FDA suggests 2 weeks for SAR and 4 weeks for PAR but the EMEA suggests 2 to 4 weeks for SAR and 6 to 12 weeks for PAR trials. In the interest of global harmonization, it would be desirable to have a uniform duration of such trials so that investigators, internationally, would be able to readily compare results for various types of treatments based on a single standard. Therefore, we performed an evidence-based review to answer the clinical question, What is the optimal duration for SAR and PAR clinical trials?

METHODS: We performed a MEDLINE search of the published literature from 1995 to the present. We used appropriate search terms, such as allergic rhinitis, seasonal allergic rhinitis, perennial allergic rhinitis, SAR, and PAR, to identify pertinent articles. These articles were reviewed and graded according to the evidence quality.

RESULTS: After an initial screening of more than 300 articles, 138 articles were analyzed thoroughly. No study specifically addressed the question of the optimal duration of SAR or PAR clinical trials.

CONCLUSIONS: We conclude that the current FDA (draft) guidelines calling for a study length of 2 weeks for the assessment of drug efficacy for SAR and 4 weeks for the study of drug efficacy in PAR are appropriate and that longer study periods are not likely to add meaningfully to the assessment of drug efficacy.

Efficacy of 2 months of allergen-specific immunotherapy with Bet v 1-derived contiguous overlapping peptides in patients with allergic rhinoconjunctivitis: Results of a phase IIb study

BACKGROUND

An immunotherapy formulation consisting of 3 contiguous overlapping peptides (COPs) derived from Bet v 1, the major birch pollen allergen, showed good clinical tolerability in a previous phase I/IIa clinical trial.

OBJECTIVES

We sought to evaluate the efficacy and safety of allergen-specific immunotherapy using 2 dose regimens of Bet v 1 COPs versus placebo in subjects with birch pollen-induced allergic rhinoconjunctivitis.

METHODS

A randomized, double-blind, placebo-controlled phase IIb clinical trial was performed to assess the efficacy of Bet v 1 COP immunotherapy during the 2013 birch pollen season. Before the season, Bet v 1 COPs (50 and 100 μg in aluminum hydroxide) or placebo (saline and aluminum hydroxide) were administered as 5 subcutaneous injections to 239 adults with allergic rhinoconjunctivitis to birch pollen. Bet v 1 COPs at 25 or 50 μg were administered on day 1, and 50 or 100 μg was administered on days 8, 15, 29, and 57, respectively. Patients were monitored for adverse events during the treatment period and assessed for combined rhinoconjunctivitis symptom and medication scores, as well as quality of life.

RESULTS

Rhinoconjunctivitis symptom and medication scores improved in both Bet v 1 COP-treated groups, reaching statistical significance over placebo in the 50-μg group (least squares mean, -0.23; 26% improvement; P = .015). Both active groups showed significant improvement in quality of life and nighttime nasal symptom scores, supporting the primary end point findings. Bet v 1 COP injections were well tolerated, with a higher frequency of systemic adverse events in the 100-μg group.

CONCLUSION

Two months of preseasonal immunotherapy with 3 COPs derived from Bet v 1 at a 50-μg dose showed promising efficacy, small risk for systemic reactions, and immunomodulatory changes in this single-season, dose-finding, phase IIb trial in patients allergic to birch pollen.

Intranasal Corticosteroid Therapy in the Treatment of Obstructive Sleep Apnea: A Meta-Analysis of Randomized Controlled Trials

Aim

To assess the efficacy of intranasal corticosteroid therapy in the treatment of obstructive sleep apnea (OSA) based on current evidence.

Methods

A number of medical literature data bases: PubMed, Cochrane Library, Scopus, and CINAHL, were searched comprehensively to identify randomized controlled trials (RCT) that reported on the efficacy of intranasal corticosteroid therapy for OSA. The selected studies were subjected to a meta-analysis and a risk-of-bias assessment.

Results

Seven RCTs met our eligibility criteria, five of these were included in our meta-analysis. The results indicated that intranasal corticosteroid therapy has a better effect in decreasing the apnea-hypopnea index compared with those participants who received placebo (standard mean difference 0.95 [95% confidence interval, -1.42 to -0.47]) (n = 221, I2 = 62%).

Conclusion

Our study results showed that patients who received intranasal corticosteroid therapy had a significant improvement in OSA. However, this evidence was limited by the potential risk of bias and heterogeneity of the selected RCTs.

Allergen immunotherapy in asthma; what is new?

The use and role of allergen immunotherapy (AIT) in asthma is still a matter of debate, and no definite recommendation about this is made in guidelines, both for the subcutaneous and sublingual routes. This is essentially due to the fact that most controlled randomised trials were not specifically designed for asthma, and that objective measures of pulmonary function were only occasionally considered. Nonetheless, in many trials, favourable results in asthma (symptoms, medication usage, bronchial reactivity) were consistently reported. There are also several meta analyses in favour of AIT, although their validity is limited by a relevant methodological heterogeneity. In addition to the crude clinical effect, a disease modifying action of AIT (prevention of asthma onset and long-lasting effects) have been reported. The safety is an important aspect to consider in asthma. Fatalities were rare: in Europe no fatality was reported in the last three decades, as in the United States in the last 4 years. Based on previous surveys, and common sense, uncontrolled asthma is still recognized as the most important risk factor for severe adverse events. On the contrary, there is no evidence that AIT can worsen or induce asthma. According to the available evidence, AIT can be safely used as add-on treatment when asthma is associated with rhinitis (a frequent condition), provided that asthma is adequately controlled by pharmacotherapy. AIT cannot be recommended or suggested as single therapy. When asthma is the unique manifestation of respiratory allergy, its use should be evaluated case by case.

Sustained efficacy and safety of a 300IR daily dose of a sublingual solution of birch pollen allergen extract in adults with allergic rhinoconjunctivitis: results of a double-blind, placebo-controlled study

Background

Allergic rhinoconjunctivitis (ARC) due to birch pollen is a growing health concern in Europe. Here, we report the efficacy and safety of 300IR birch pollen sublingual solution administered discontinuously for 2 consecutive years to patients with birch-associated allergic rhinoconjunctivitis.

Methods

Birch pollen-allergic adults were randomized in this double blind study to 300IR birch pollen sublingual solution or placebo, daily, starting 4 months before and continuing through the pollen season for two pollen seasons. Randomization was stratified according to the presence or absence of oral allergy syndrome (OAS). The primary efficacy endpoint was the Average Adjusted Symptom Score (AAdSS) over the second pollen season and was analyzed by ANCOVA. Secondary efficacy endpoints included the AAdSS over the first pollen period. Safety was evaluated by means of adverse event monitoring.

Results

574 patients (284 in the active group and 290 in the placebo group) were randomized and 496 completed the study. Over the second pollen period, the least square (LS) mean AAdSS was significantly lower in the 300IR group than in the placebo group (LS mean difference −2.04, 95% CI [−2.69, −1.40], (p <0.0001) with a relative reduction of 30.6%. Results were consistent in patients with and without OAS (−33.6% and −28.4%, respectively). A significant reduction in LS mean AAdSS was also observed over the first pollen season. The most frequently reported adverse events were application site reactions: oral pruritus, throat irritation, and mouth edema. There were no reports of anaphylaxis.

Conclusions

Pre- and co-seasonal treatment with 300IR birch pollen sublingual solution demonstrated sustained clinical efficacy over 2 pollen seasons and was well tolerated in adults with birch pollen-associated allergic rhinoconjunctivitis. Efficacy results were consistent in patients with and without oral allergy syndrome.

Trial registration

ClinicalTrials.gov: NCT01731249.

Specific immunotherapy in asthma: a comprehensive review

BACKGROUND

The prescription of allergen immunotherapy (SIT) in asthma remains a matter of debate and official guidelines often do not provide clear recommendations in this regard.

METHODS

An extensive review of the literature was untaken.

RESULTS

There are many robust studies with SCIT and SLIT showing positive results related to improving asthma symptoms, in particular when asthma was associated with rhinitis. In addition, there are several favourable meta-analyses, although their validity is limited by the heterogeneity of the trials included. The disease modifying effect of SIT (prevention of asthma onset and long-lasting effects) should be considered when prescribing this treatment. Regarding safety, fatalities seem to be rare: in Europe no fatality has been reported over the last two decades, and the same has been observed in USA in the last 4 years. Uncontrolled asthma is universally recognized as the most important risk factor for severe adverse events, but there is no clear demonstration that SIT can worsen or induce asthma. In contrast, of the few studies specifically designed to evaluate asthma, none had a formal sample size calculation, and pulmonary function was assessed as primary outcome only sporadically.

CONCLUSIONS

According to the presently available evidence, SLIT and SCIT can be used in asthma associated with rhinitis (the most common condition), provided that asthma is adequately controlled by pharmacotherapy. In such cases, a measurable clinical benefit on asthma symptoms can be expected. SIT cannot be presently recommended as single therapy when asthma is the unique manifestation of respiratory allergy.

[Birch pollen allergy]

In the North-East of France, birch is the main tree responsible of spring pollen allergy. However, the epidemiology of sensitization to birch pollen remains unclear. Monosensitization to birch pollen seems rare because of the frequency of cross-reactions with other pollens of the same botanical family via the major allergen Bet v 1. Around one third of patients with allergic rhinoconjunctivitis due to birch pollen are also asthmatics and a half suffer from a food allergy, essentially an oral syndrome due to rosaceae fruits eaten raw. The molecular allergens of birch pollen are well-known and have been cloned. They are available for use in in vitro diagnostic tests and also in clinical trials of specific immunotherapy.

Impact of intranasal corticosteroids on asthma outcomes in allergic rhinitis: a meta-analysis

Given the relationship between allergic rhinitis (AR) and asthma, it can be hypothesized that reducing inflammation in the upper airway with intranasal corticosteroid (INCS) medications may improve asthma outcomes. The goal of this study was to perform a systematic review with meta-analysis of the efficacy of INCS medications on asthma outcomes in patients with AR and asthma. Asthma-specific outcomes from randomized, controlled studies evaluating INCS medications in patients with AR were evaluated, including studies that compared INCS sprays to placebo, INCS sprays plus orally inhaled corticosteroids to orally inhaled corticosteroids alone, and nasally inhaled corticosteroids to placebo. Sufficient data for meta-analysis were retrieved for 18 trials with a total of 2162 patients. Asthma outcomes included pulmonary function, bronchial reactivity, asthma symptom scores, asthma-specific quality of life, and rescue medication use. The subgroup of studies comparing INCS spray to placebo had significant improvements in FEV1 (SMD = 0.31; 95% CI, 0.04-0.58), bronchial challenge (SMD = 0.46; 95% CI, 0.12-0.79), asthma symptom scores (SMD = -0.42; 95% CI, -0.53 to -0.30), and rescue medication use (SMD = -0.29; 95% CI, -0.58 to -0.01). Nasal inhalation of corticosteroids significantly improved morning and evening peak expiratory flow. There were no significant changes in asthma outcomes with the addition of INCS spray to orally inhaled corticosteroids. Thus, the results of this meta-analysis demonstrated that intranasal corticosteroid medications significantly improve some asthma-specific outcome measures in patients suffering from both AR and asthma. This effect was most pronounced with INCS sprays when patients were not on orally inhaled corticosteroids, or when corticosteroid medications were inhaled through the nose into the lungs. Overall, intranasal corticosteroid medications improve some asthma-specific outcome measures in patients with both AR and asthma. Further research is needed to clarify the role of INCS sprays as asthma-specific therapy, as well as the role of the nasal inhalation technique as a monotherapy in patients suffering from both asthma and AR.

Effectiveness of subcutaneous immunotherapy for allergic rhinoconjunctivitis and asthma: a systematic review

OBJECTIVES/HYPOTHESIS

To systematically review the effectiveness and safety of subcutaneous immunotherapy (SCIT) for treatment of allergic rhinoconjunctivitis and asthma, using formulations currently approved in the United States.

STUDY DESIGN

We searched the following databases up to May 21, 2012: MEDLINE, Embase, LILACS, and the Cochrane Central Register of Controlled Trials.

METHODS

We included randomized controlled trials published in English comparing SCIT to placebo, pharmacotherapy, or other SCIT regimens that reported clinical outcomes of interest. Studies of adults or mixed age populations were included. Studies were excluded if the diagnosis of allergy and/or asthma was not confirmed with objective testing. Paired reviewers selected articles for inclusion and extracted data. We assessed the risk of bias for each study and graded the strength of evidence for each outcome as high, moderate, or low.

RESULTS

Sixty-one studies met our inclusion criteria. Majority of the studies (66%) evaluated single-allergen immunotherapy regimens. The literature provides high-grade evidence that SCIT reduces asthma symptoms, asthma medication usage, rhinitis/rhinoconjunctivitis symptoms, conjunctivitis symptoms, and rhinitis/rhinoconjunctivitis disease-specific quality of life in comparison to placebo or usual care. There is moderate evidence that SCIT decreases rhinitis/rhinoconjunctivitis medication usage. Respiratory reactions were the most common systemic reaction. There were few reports of anaphylaxis; no deaths were reported.

CONCLUSIONS

Generally moderate to strong evidence supports the effectiveness of SCIT for treatment of allergic rhinitis and asthma, particularly with single-allergen immunotherapy regimens. Adverse reactions to SCIT are common, but no deaths were reported in the included studies.

Intermittent versus daily inhaled corticosteroids for persistent asthma in children and adults

BACKGROUND

Daily inhaled corticosteroids (ICS) are the recommended mainstay of treatment in children and adults with persistent asthma. However, often, ICS are used intermittently by patients or recommended by physicians to be used only at the onset of exacerbations.

OBJECTIVES

The aim of this review was to compare the efficacy and safety of intermittent versus daily ICS in the management of children and adults with persistent asthma and preschool-aged children suspected of persistent asthma.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials (CAGR) and the ClinicalTrials.gov web site up to October 2012.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared intermittent ICS versus daily ICS in children and adults with persistent asthma. No co-interventions were permitted other than rescue relievers and oral corticosteroids used during exacerbations.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, methodological quality and extracted data. The primary efficacy outcome was the number of patients with one or more exacerbations requiring oral corticosteroids and the primary safety outcome was the number of patients with serious adverse health events. Secondary outcomes included exacerbations, lung function tests, asthma control, adverse effects, withdrawal rates and inflammatory markers. Equivalence was assumed if the risk ratio (RR) estimate and its 95% confidence interval (CI) were between 0.9 and 1.1. Quality of the evidence was assessed using GRADE.

MAIN RESULTS

Six trials (including one trial testing two relevant protocols) met the inclusion criteria for a total of seven group comparisons. The four paediatric trials (two involving preschool children and two school-aged children) and two adult parallel-group trials, lasting 12 to 52 weeks, were of high methodological quality. A total of 1211 patients with confirmed, or suspected, persistent asthma contributed to the meta-analyses. There was no statistically significant group difference in the risk of patients experiencing one or more exacerbations requiring oral corticosteroids (1204 patients; RR 1.07; 95% CI 0.87 to 1.32; the large confidence interval translates into a risk of exacerbations in the intermittent ICS group varying between 17% and 25%, assuming a 19% risk with daily ICS). Age, severity of airway obstruction, step-up protocol used during exacerbations and trial duration did not significantly influence the primary efficacy outcome. No group difference was observed in the risk of patients with serious adverse health events (1055 patients; RR 0.82; 95% CI 0.33 to 2.03). Compared to the daily ICS group, the intermittent ICS group displayed a smaller improvement in change from baseline peak expiratory flow rate (PEFR) by 2.56% (95% CI -4.49% to -0.63%), fewer symptom-free days (standardised mean difference (SMD) -0.15 (95% CI -0.28 to -0.03), fewer asthma control days -9% (95% CI -14% to -4%), more use of rescue β2-agonists by 0.12 puffs/day (95% CI 0 to 0.23) and a greater increase from baseline in exhaled nitric oxide of 16.80 parts per billion (95% CI 11.95 to 21.64). There was no significant group difference in forced expiratory volume in one second (FEV1), quality of life, airway hyper-reactivity, adverse effects, hospitalisations, emergency department visits or withdrawals. In paediatric trials, intermittent ICS (budesonide and beclomethasone) were associated with greater growth by 0.41 cm change from baseline (532 children; 95% CI 0.13 to 0.69) compared to daily treatment.

AUTHORS' CONCLUSIONS

In children and adults with persistent asthma and in preschool children suspected of persistent asthma, there was low quality evidence that intermittent and daily ICS strategies were similarly effective in the use of rescue oral corticosteroids and the rate of severe adverse health events. The strength of the evidence means that we cannot currently assume equivalence between the two options.. Daily ICS was superior to intermittent ICS in several indicators of lung function, airway inflammation, asthma control and reliever use. Both treatments appeared safe, but a modest growth suppression was associated with daily, compared to intermittent, inhaled budesonide and beclomethasone. Clinicians should carefully weigh the potential benefits and harm of each treatment option, taking into account the unknown long-term (> one year) impact of intermittent therapy on lung growth and lung function decline.

Intermittent versus daily inhaled corticosteroids for persistent asthma in children and adults

BACKGROUND

Daily inhaled corticosteroids (ICS) are the recommended mainstay of treatment in children and adults with persistent asthma. Yet often, ICS are used intermittently by patients or recommended by physicians to be used only at the onset of exacerbations.

OBJECTIVES

The aim of this review was to compare the efficacy and safety of intermittent versus daily ICS in the management of children and adults with persistent asthma and preschool-aged children suspected of persistent asthma.

SEARCH METHODS

We searched the Cochrane Airways Group Specialised Register of trials (CAGR) and the ClinicalTrials.gov website up to December 2011.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that compared intermittent ICS versus daily ICS in children and adults with persistent asthma. No co-interventions were permitted other than rescue relievers and oral corticosteroids used during exacerbations.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, methodological quality and extracted data. The primary efficacy outcome was the number of patients with one or more exacerbations requiring oral corticosteroids and the primary safety outcome was the number of patients with serious adverse health events. Secondary outcomes included exacerbations, lung function tests, asthma control, adverse effects, withdrawal rates and inflammatory markers. Equivalence was assumed if the risk ratio (RR) estimate and its 95% confidence interval (CI) were between 0.9 and 1.1.

MAIN RESULTS

Six trials (including one trial testing two relevant protocols) met the inclusion criteria for a total of seven group comparisons. The four paediatric trials (two involving preschool children and two school-aged children) and two adult parallel-group trials, lasting 12 to 52 weeks, were of high methodological quality. A total of 1211 patients with confirmed, or suspected, persistent asthma contributed to the meta-analyses. There was no statistically significant group difference in the risk of patients experiencing one or more exacerbations requiring oral corticosteroids (1204 patients; RR 1.07; 95% CI 0.87 to 1.32). The patients' age, severity of airway obstruction, step-up protocol used during exacerbations and trial duration did not significantly influence the primary efficacy outcome. No group difference was observed in the risk of patients with serious adverse health events (1055 patients; RR 0.82; 95% CI 0.33 to 2.03). Compared to the daily ICS group, the intermittent ICS group displayed a smaller improvement in change from baseline peak expiratory flow rate (PEFR) by 2.56% (95% CI -4.49% to -0.63%), fewer symptom-free days (standardised mean difference (SMD) -0.15 (95% CI -0.28 to -0.03), fewer asthma control days -9% (95% CI -14% to -4%), more use of rescue β(2)-agonists by 0.12 puffs/day (95% CI 0 to 0.23) and a greater increase from baseline in exhaled nitric oxide of 16.80 parts per billion (95% CI 11.95 to 21.64). There was no significant group difference in forced expiratory volume in one second (FEV(1)), quality of life, airway hyper-reactivity, adverse effects, hospitalisations, emergency department visits or withdrawals. In paediatric trials, intermittent ICS (budesonide and beclomethasone) were associated with greater growth by 0.41 cm change from baseline (532 children; 95% CI 0.13 to 0.69) compared to daily treatment.

AUTHORS' CONCLUSIONS

In children and adults with persistent asthma and in preschool children suspected of persistent asthma, intermittent and daily ICS strategies did not significantly differ in the use of rescue oral corticosteroids and the rate of severe adverse health events, neither did they reach equivalence. Daily ICS was superior to intermittent ICS in several indicators of lung function, airway inflammation, asthma control and reliever use. Both treatments appeared safe, but a modest growth suppression was associated with daily, compared to intermittent, inhaled budesonide and beclomethasone. The clinician should carefully weigh the potential benefits and harm of each treatment option, taking into account the unknown long-term (> one year) impact of intermittent therapy on lung growth and lung function decline.

The role of immunotherapy in the management of childhood asthma

Subcutaneous immunotherapy (SCIT) is still questioned as a safe and efficacious way of treating allergic asthma in children. In a Cochrane review published in 2010 it was, however, concluded that SCIT has significant and beneficial effects on symptoms and medication use in both children and adults with mostly mild asthma. Only a few studies have been performed to specifically study if SCIT in children with moderate asthma reduces the need for inhaled corticosteroids. There are conflicting results that illustrate the problem of the heterogeneity of the asthma disease and the fact that allergies may play different roles on the severity and symptoms of the disease. Furthermore, children with severe allergic asthma are often sensitized to multiple allergens, which makes SCIT both complicated and less safe to administer. On the other hand, if the child suffers from asthmatic symptoms despite adherence to pharmacotherapy, omalizumab or a combination of omalizumab and allergen immunotherapy might be useful. There is a need for more studies on this combination before it can be considered as an additional therapy in children with asthma and severe allergies. Sublingual immunotherapy (SLIT) has also been shown to improve asthma symptoms and medication use. SLIT is safe although its efficacy compared with SCIT has been studied very little. Another approach is to try to prevent asthma by treating children with SCIT for allergic rhinoconjunctivitis before asthma has developed. The most attractive prospect, however, is to find ways of preventing asthma by vaccination against the most common viruses, particularly rhinovirus. There is evidence that there are children at high risk of developing asthma in whom a viral infection can also enhance the risk of allergen sensitization. So far this vaccination has not been achievable although research is in progress.

Effect of an intranasal corticosteroid on exercise induced bronchoconstriction in asthmatic children

RATIONALE

Allergic rhinitis and exercise induced bronchoconstriction (EIB) are common in asthmatic children. The aim of this study was to investigate whether treatment of allergic rhinitis with an intranasal corticosteroid protects against EIB in asthmatic children.

METHODS

This was a double-blind, randomized, placebo-controlled, parallel group study. Subjects aged 12-17 years, with mild-to-moderate asthma, intermittent allergic rhinitis and ≥ 10% fall in FEV(1) at a screening exercise challenge were randomized to 22 ± 3 days treatment with intranasal fluticasone furoate or placebo. The primary outcome was change in exercise induced fall in FEV(1) . Secondary outcomes were changes in the area under the curve (AUC), asthma control questionnaire (ACQ), pediatric asthma quality of life questionnaire (PAQLQ), and exhaled nitric oxide (FeNO).

RESULTS

Twenty-five children completed the study. Mean exercise induced fall in FEV(1) (± SD) decreased significantly (95% CI: 0.7-18.2%, P = 0.04) in the fluticasone furoate group from 28.4 ± 15.8% to 19.0 ± 13.8%, compared to the placebo group (27.4 ± 16.0% to 27.4 ± 19.2%). The change in AUC was not significantly different between treatment groups. However, within the fluticasone furoate group the AUC decreased significantly (P = 0.01). Although total PAQLQ score did not improve, the activity limitation domain score improved significantly within the fluticasone furoate group (P = 0.03). No significant changes were observed in FeNO and ACQ.

CONCLUSION

Treatment of allergic rhinitis in asthmatic children with an intranasal corticosteroid reduces EIB and tends to improve quality of life.

Specific immunotherapy in asthma: efficacy and safety

The use of specific immunotherapy (SIT) to treat asthma has been, and still is, a matter of debate, and there are no clear or unequivocal indications in the official documents. This is partly due to the fact that there are few studies specifically designed to assess asthma, that none of such studies had a formal sample size calculation, and that objective parameters of pulmonary function have been assessed only sporadically. Nonetheless, there are good quality studies for both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) where asthma symptoms were evaluated, and showing positive results. Moreover, several favourable meta-analyses are available, although their validity is limited by the great heterogeneity of the trials included. The disease modifying effect of SIT, that is the capacity of preventing asthma onset should be also taken into account. Concerning the safety, fatalities seem to be an exceptional event and in Europe no fatality has been reported over the last two decades. Uncontrolled asthma is universally recognized as the most important risk factor for severe adverse events. In conclusion both SLIT and SCIT can be used in asthma associated with rhinitis (which is the most common condition), provided that asthma is adequately controlled by pharmacotherapy. In such case, a measurable clinical benefit on asthma symptoms can be expected. On the other hand, SIT cannot be presently recommended as single therapy when asthma is the unique manifestation of respiratory allergy.

Effect of allergen-specific immunotherapy with purified Alt a1 on AMP responsiveness, exhaled nitric oxide and exhaled breath condensate pH: a randomized double blind study

Background

Little information is available on the effect of allergen-specific immunotherapy on airway responsiveness and markers in exhaled air. The aims of this study were to assess the safety of immunotherapy with purified natural Alt a1 and its effect on airway responsiveness to direct and indirect bronchoconstrictor agents and markers in exhaled air.

Methods

This was a randomized double-blind trial. Subjects with allergic rhinitis with or without mild/moderate asthma sensitized to A alternata and who also had a positive skin prick test to Alt a1 were randomized to treatment with placebo (n = 18) or purified natural Alt a1 (n = 22) subcutaneously for 12 months. Bronchial responsiveness to adenosine 5'-monophosphate (AMP) and methacholine, exhaled nitric oxide (ENO), exhaled breath condensate (EBC) pH, and serum Alt a1-specific IgG₄ antibodies were measured at baseline and after 6 and 12 months of treatment. Local and systemic adverse events were also registered.

Results

The mean (95% CI) allergen-specific IgG₄ value for the active treatment group increased from 0.07 μg/mL (0.03-0.11) at baseline to 1.21 μg/mL (0.69-1.73, P < 0.001) at 6 months and to 1.62 μg/mL (1.02-2.22, P < 0.001) at 12 months of treatment. In the placebo group, IgG₄ value increased nonsignificantly from 0.09 μg/mL (0.06-0.12) at baseline to 0.13 μg/mL (0.07-0.18) at 6 months and to 0.11 μg/mL (0.07-0.15) at 12 months of treatment. Changes in the active treatment group were significantly higher than in the placebo group both at 6 months (P < 0.001) and at 12 months of treatment (P < 0.0001). However, changes in AMP and methacholine responsiveness, ENO and EBC pH levels were not significantly different between treatment groups. The overall incidence of adverse events was comparable between the treatment groups.

Conclusion

Although allergen-specific immunotherapy with purified natural Alt a1 is well tolerated and induces an allergen-specific IgG₄ response, treatment is not associated with changes in AMP or methacholine responsiveness or with significant improvements in markers of inflammation in exhaled air. These findings suggest dissociation between the immunotherapy-induced increase in IgG₄ levels and its effect on airway responsiveness and inflammation.

Injection allergen immunotherapy for asthma

BACKGROUND

Allergen specific immunotherapy has long been a controversial treatment for asthma. Although beneficial effects upon clinically relevant outcomes have been demonstrated in randomised controlled trials, there remains a risk of severe and sometimes fatal anaphylaxis. The recommendations of professional bodies have ranged from cautious acceptance to outright dismissal. With increasing interest in new allergen preparations and methods of delivery, we updated the systematic review of allergen specific immunotherapy for asthma.

OBJECTIVES

The objective of this review was to assess the effects of allergen specific immunotherapy for asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group Trials Register up to 2005, Dissertation Abstracts and Current Contents.

SELECTION CRITERIA

Randomised controlled trials using various forms of allergen specific immunotherapy to treat asthma and reporting at least one clinical outcome.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed eligibility of studies for inclusion. Two authors independently performed quality assessment of studies.

MAIN RESULTS

Eighty-eight trials were included (13 new trials). There were 42 trials of immunotherapy for house mite allergy; 27 pollen allergy trials; 10 animal dander allergy trials; two Cladosporium mould allergy, two latex and six trials looking at multiple allergens. Concealment of allocation was assessed as clearly adequate in only 16 of these trials. Significant heterogeneity was present in a number of comparisons. Overall, there was a significant reduction in asthma symptoms and medication, and improvement in bronchial hyper-reactivity following immunotherapy. There was a significant improvement in asthma symptom scores (standardised mean difference -0.59, 95% confidence interval -0.83 to -0.35) and it would have been necessary to treat three patients (95% CI 3 to 5) with immunotherapy to avoid one deterioration in asthma symptoms. Overall it would have been necessary to treat four patients (95% CI 3 to 6) with immunotherapy to avoid one requiring increased medication. Allergen immunotherapy significantly reduced allergen specific bronchial hyper-reactivity, with some reduction in non-specific bronchial hyper-reactivity as well. There was no consistent effect on lung function. If 16 patients were treated with immunotherapy, one would be expected to develop a local adverse reaction. If nine patients were treated with immunotherapy, one would be expected to develop a systemic reaction (of any severity).

AUTHORS' CONCLUSIONS

Immunotherapy reduces asthma symptoms and use of asthma medications and improves bronchial hyper-reactivity. One trial found that the size of the benefit is possibly comparable to inhaled steroids. The possibility of local or systemic adverse effects (such as anaphylaxis) must be considered.

Long-term comparison of sublingual immunotherapy vs inhaled budesonide in patients with mild persistent asthma due to grass pollen

BACKGROUND

Few studies have compared the effects of immunotherapy and inhaled steroids. The main limitation of such studies is the long duration required to fully appreciate the effects of immunotherapy.

OBJECTIVE

To compare the effects of inhaled budesonide and sublingual immunotherapy (SLIT) in mild persistent asthma for up to 5 years.

METHODS

Patients with mild persistent asthma and rhinitis due to grass pollen were enrolled in an open randomized controlled trial. After a run-in season, they were randomized to either budesonide, 800 microg/d, in the pollen season or continuous grass SLIT for 5 years. All patients received rescue medications. Symptoms were evaluated by diary cards filled out from May to July at baseline and after 3 and 5 years. In-season nasal eosinophils and bronchial hyperresponsiveness were also assessed.

RESULTS

Fifty-one patients were enrolled and 46 completed the study. The bronchial symptom scores and the use of bronchodilators decreased significantly in both groups, but the improvement was greater in the SLIT patients at 3 and 5 years. The nasal symptom score and the intake of nasal steroids decreased only in the SLIT group, and the difference vs the budesonide group was always significant. In the SLIT group vs the budesonide group, a statistically significant decrease of nasal eosinophils was found at 3 and 5 years (P < .01). The bronchial hyperresponsiveness improved significantly only in the SLIT group.

CONCLUSION

In patients with grass pollen-induced asthma, in the long term SLIT was equally effective as inhaled budesonide in treating bronchial symptoms and provided an additional benefit in treating rhinitis symptoms and bronchial hyperresponsiveness.

Nature of regulatory T cells in the context of allergic disease

Allergen-specific immunotherapy (SIT) is the cornerstone of the management of allergic diseases, which targets modification of the immunologic response, along with environmental allergen avoidance and pharmacotherapy. SIT is associated with improved tolerance to allergen challenge, with a decrease in immediate-phase and late-phase allergic inflammation. SIT has the potential to prevent development of new sensitizations and progression of allergic rhinitis to asthma. It has a role in cellular and humoral responses in a modified pattern. The ratio of T helper (Th)1 cytokines to Th2 cytokines is increased following SIT, and functional regulatory T cells are induced. Interleukin-10 production by monocytes, macrophages, and B and T cells is increased, as well as expression of transforming growth factor β. SIT is associated with increases in allergen-specific antibodies in IgA, IgG1, and IgG4 isotypes. These blocking-type immunoglobulins, particularly IgG4, may compete with IgE binding to allergen, decreasing the allergen presentation with the high- and low-affinity receptors for IgE (FcεRI and FcεRII, respectively). Additionally, SIT reduces the number of mast cells and eosinophils in the target tissues and release of mediators from these cells.

Nasobronchial interaction mechanisms in allergic airways disease

PURPOSE OF REVIEW

During the past few decades, the incidence of sensitization to inhaled allergens as well as allergic airways disease has grown steadily. Genetic and environmental factors are recognized as etiologic factors in the development of allergic airway disease, with allergic rhinitis often preceding the development of asthma. Allergic rhinitis is considered a risk factor for the development of asthma, and almost all allergic asthmatic patients have rhinitis. Insight into the risk factors responsible for allergic airways disease and the interaction between the involved organs results in a better diagnostic and therapeutic approach in global airway allergy syndrome.

RECENT FINDINGS

Recent studies have shown that local tissue factors, such as microbial stimuli and systemic inflammatory mechanisms, play a role in the clinical expression of the allergic airway syndrome. In addition, impaired nasal function affects the lower airways of asthmatic patients via different pathways. To date, most human and animal data point towards a systemic pathway linking the upper and lower airways, involving both bloodstream and bone marrow. Recent clinical trials and current guidelines underline the importance of an integrated treatment strategy involving both ends of the respiratory tract.

SUMMARY

This review provides an overview of recent epidemiological and immunopathologic evidence concerning the link between upper and lower airways in allergic disease and its therapeutic implications.

Allergic rhinitis and its impact on asthma update: allergen immunotherapy

The Allergic Rhinitis and its Impact on Asthma document was first published in 2001. Since then, new data on specific immunotherapy have appeared. This review is intended as an update to the original document. MedLine (2001 to June 2006) was searched with appropriate key words, and panelists were asked to identify further relevant articles. Randomized controlled trials were considered for the evaluation of efficacy. For the evaluation of safety and additional effects, studies with lower grades of evidence were included. The clinical efficacy of injection immunotherapy in rhinitis and asthma was confirmed, as well as the safety, provided that recommendations are followed. Studies have demonstrated the long-term efficacy and the preventive effect of immunotherapy in reducing the onset of new sensitizations. One randomized open trial demonstrated that in children with allergic rhinitis, injection immunotherapy may reduce the risk of developing asthma. There is strong evidence that sublingual immunotherapy is effective in allergic rhinitis in adults. Recent meta-analyses demonstrated its efficacy in allergic rhinitis in children and in asthma, although more definitive trials are required. Current data indicate that sublingual immunotherapy is safe and the rate of adverse reactions is not greater below 5 years of age. One randomized open trial showed that in children with allergic rhinitis, sublingual immunotherapy reduced the onset of asthma. Further studies are needed to identify the optimal maintenance dose and to elucidate the mechanism of action. Novel approaches for immunotherapy are currently under evaluation, including the use of adjuvants, peptides, and DNA-conjugated and recombinant allergens.

Allergen injection immunotherapy for seasonal allergic rhinitis

BACKGROUND

Allergic rhinitis is the most common of the allergic diseases. Despite improved understanding of the pathophysiology of allergic rhinitis and advances in its pharmacological treatment, its prevalence has increased worldwide. For patients whose symptoms remain uncontrolled despite medical treatment, allergen injection immunotherapy is advised. An allergen-based treatment may reduce symptoms, the need for medication and modify the natural course of this disease.

OBJECTIVES

To evaluate the efficacy and safety of subcutaneous specific allergen immunotherapy, compared with placebo, for reducing symptoms and medication requirements in seasonal allergic rhinitis patients.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 1 2006), MEDLINE (1950 to 2006), EMBASE (1974 to 2006), Pre-MEDLINE, KOREAMED, INDMED, LILACS, PAKMEDINET, Scisearch, mRCT and the National Research Register. The date of the last search was February 2006.

SELECTION CRITERIA

All studies identified by the searches were assessed to identify randomised controlled trials involving participants with symptoms of seasonal allergic rhinitis and proven allergen sensitivity, treated with subcutaneous allergen specific immunotherapy or corresponding placebo.

DATA COLLECTION AND ANALYSIS

Two independent authors identified all studies reporting double-blind, placebo controlled randomised trials of specific immunotherapy in patients with seasonal allergic rhinitis due to tree, grass or weed pollens. Two authors independently performed quality assessment of studies. Data from identified studies were abstracted onto a standard extraction sheet and subsequently entered into RevMan 4.2.8. Analysis was performed using the Standardised Mean Difference (SMD) method and a random-effects model; P values < 0.05 were considered statistically significant. The primary outcome measures were symptom scores, medication use, quality of life and adverse events.

MAIN RESULTS

We retrieved 1111 publications of which 51 satisfied our inclusion criteria. In total there were 2871 participants (1645 active, 1226 placebo), each receiving on average 18 injections. Duration of immunotherapy varied from three days to three years. Symptom score data from 15 trials were suitable for meta-analysis and showed an overall reduction in the immunotherapy group (SMD -0.73 (95% CI -0.97 to -0.50, P < 0.00001)). Medication score data from 13 trials showed an overall reduction in the immunotherapy group (SMD of -0.57 (95% CI -0.82 to -0.33, p<0.00001)). Clinical interpretation of the effect size is difficult. Adrenaline was given in 0.13% (19 of 14085 injections) of those on active treatment and in 0.01% (1 of 8278 injections) of the placebo group for treatment of adverse events. There were no fatalities.

AUTHORS' CONCLUSIONS

This review has shown that specific allergen injection immunotherapy in suitably selected patients with seasonal allergic rhinitis results in a significant reduction in symptom scores and medication use. Injection immunotherapy has a known and relatively low risk of severe adverse events. We found no long-term consequences from adverse events.

Immunological mechanisms of allergen-specific immunotherapy

Allergen-specific immunotherapy has been carried out for almost a century and remains one of the few antigen-specific treatments for inflammatory diseases. The mechanisms by which allergen-specific immunotherapy exerts its effects include the modulation of both T-cell and B-cell responses to allergen. There is a strong rationale for improving the efficacy of allergen-specific immunotherapy by reducing the incidence and severity of adverse reactions mediated by IgE. Approaches to address this problem include the use of modified allergens, novel adjuvants and alternative routes of administration. This article reviews the development of allergen-specific immunotherapy, our current understanding of its mechanisms of action and its future prospects.

Clinical efficacy and safety of sublingual immunotherapy with tree pollen extract in children

BACKGROUND

Subcutaneous immunotherapy has been the principal approach of immunotherapy in the treatment of allergic diseases. Several clinical studies with birch, alder or hazel pollen extract conducted as subcutaneous immunotherapy have been published suggesting a well-tolerated and clinically effective treatment. Only a few clinical studies of sublingual immunotherapy (SLIT) with these allergens have been published. This study investigated the clinical efficacy, safety and dose-response relationship of SLIT in children suffering from rhinoconjunctivitis with/without asthma.

METHODS

Eighty-eight children (5-15 years) with a history of tree pollen-induced allergic rhinoconjunctivitis with/without seasonal asthma for >or=2 years were included. Allergy to tree pollen was confirmed by positive skin-prick test, positive specific IgE and positive conjunctival provocation test. The extract used was a glycerinated mixture of Betula verrucosa, Corylus avellana and Alnus glutinosa 100,000 SQ-U/ml. Children were randomized into three groups receiving SLIT 5 days a week for up to 18 months; dose group 1: accumulated weekly dose of 24,000 SQ-U; dose group 2: accumulated weekly dose of 200,000 SQ-U; and placebo.

RESULTS

In the birch pollen season, dose group 2 showed a significant reduction of symptom (P = 0.01) and medication scores (P = 0.04) compared with placebo. Dose group 1 showed a significant reduction of symptom scores (P = 0.03). There were no statistical differences between dose groups 1 and 2. All children tolerated the treatment well.

CONCLUSION

SLIT with tree pollen extract provided dose-dependent benefits in tree pollen-allergic children in terms of significantly reduced symptoms and medication use. The treatment was well tolerated.

Steroid-sparing effect of subcutaneous SQ-standardised specific immunotherapy in moderate and severe house dust mite allergic asthmatics

BACKGROUND

The present study evaluated the steroid-sparing effect of subcutaneous SQ-standardized specific immunotherapy (SIT) in moderate and severe house dust mite (HDM) allergic asthmatics.

METHODS

Fifty-four adult asthmatics allergic to HDM requiring at least inhaled corticosteroids (ICS) doses equivalent to 500 microg fluticasone propionate daily were randomized to subcutaneous SIT or placebo injections for a period of 3 years. The minimum required ICS dose, 4 week diary of asthma symptom score, use of rescue medication, peak expiratory flow (PEF) measurements and visual analog scale for asthma symptoms were assessed before start of treatment and after 1, 2 and 3 years of treatment.

RESULTS

In patients with moderate and severe asthma, the reduction in ICS was statistical significant after 2 years of treatment (P = 0.03) but not after 3 years. The median reductions were 82% and 42% after the third year for active and placebo respectively. In patients with moderate persistent asthma the reduction was statistical significant larger for those treated with SIT compared with placebo after year 2 and year 3. The median reductions after 3 years were 90% for SIT and 42% for placebo (P = 0.04). Despite significant steroid reduction, there was no difference in asthma assessments between the two groups. No serious reactions related to SIT injections were seen.

CONCLUSION

This study shows that SIT with a SQ-standardized HDM extract is safe. An ICS sparing effect was evident in patients with moderate persistent asthma.

Efficacy and safety of mometasone furoate vs nedocromil sodium as prophylactic treatment for moderate/severe seasonal allergic rhinitis

BACKGROUND

The preventive use of medications has been proposed to be effective in the treatment of seasonal rhinitis.

OBJECTIVE

To evaluate the efficacy and safety of mometasone furoate and nedocromil sodium nasal sprays as prophylactic treatment for moderate to severe seasonal allergic rhinitis (SAR).

PATIENTS

Sixty-one patients were recruited from 3 referral allergy centers. Inclusion criteria were history of SAR for 2 years or longer, sensitization to relevant local pollen (grasses, Parietaria, and olive), and age older than 12 years.

METHODS

An open-label, randomized, parallel-group, "real-life" study design was used. Patients received mometasone furoate nasal spray once daily or nedocromil sodium nasal spray 3 times daily starting 2 to 4 weeks before the pollen season and continuing for up to 4 months. Instructions regarding the use of additional medications were given. Diary cards recording symptoms, use of medication, and adverse events were kept by the patients.

RESULTS

All 61 patients completed the study. The prophylactic use of mometasone furoate vs nedocromil sodium led to significantly more days without symptoms (75.1% vs 54.5%; P < .001). The mometasone furoate group also had lower nasal symptom scores (mean, 1.4 vs 2.9; median, 0 vs 2; P < .001) and was more satisfied (93.1% vs 43.5%; P < .001). No serious adverse event was recorded, and there was no difference between the treatments in any adverse event.

CONCLUSIONS

Prophylactic administration of mometasone furoate before the pollen season is safe and may lead to improved control of SAR compared with the use of nedocromil sodium.

Comparison of nasal immunohistology in patients with seasonal rhinoconjunctivitis treated with topical steroids or specific allergen immunotherapy

BACKGROUND

Specific allergen immunotherapy (SIT) and nasal steroids (NS) are considered effective anti-inflammatory treatments for allergic rhinitis, although their mechanism of action differs.

OBJECTIVE

The aim of this study was to examine the effect of treatment with NS and SIT on different populations of inflammatory cells in the nasal mucosa and to compare cell numbers before and during the birch pollen season in patients with seasonal allergic rhinitis.

METHODS

In a randomized, double-blind, double dummy comparative study, 41 patients with seasonal rhinoconjunctivitis were treated with birch SIT or NS (budesonide 400 microg daily). Treatment with NS started before the birch pollen season and at the same time SIT-treated patients reached the maintenance dose. Nasal biopsies for immunohistochemistry were obtained before the season and start of the treatments and at the peak of the pollen season during treatment.

RESULTS

Symptoms of rhinoconjunctivitis increased significantly in both groups during the pollen season but less in the NS-treated group and the difference between the treatment groups was significant at the end of the season (P = 0.03). Immunohistochemistry of nasal biopsies from NS-treated patients showed significantly fewer CD1a+, IgE+ and Fc epsilonRI+ cells during the season compared with preseason (P = 0.02, P = 0.001 and P = 0.0004, respectively) and with seasonal values of the SIT-treated group (P = 0.002, P = 0.002 and P = 0.0004 respectively).

CONCLUSION

Treatment with NS but not SIT decreased the numbers of CD1a+, IgE+ and Fc epsilonRI+ cells during the birch pollen season. Our data indicate that treatment with NS has a broader anti-inflammatory range than SIT.

Characteristics of patients with seasonal allergic rhinitis and concomitant asthma

BACKGROUND

Allergic rhinitis and asthma often co-exist and appear to produce a continuum of airway disease, but whether the clinical characteristics of asthma in patients with seasonal rhinitis differ from those of persistent asthma has not been examined.

OBJECTIVE

The aim of this retrospective study was to characterize the clinical features of patients with seasonal allergic rhinitis with concomitant asthma and to compare them with those in patients with persistent asthma.

METHODS

The patient populations for this study were derived from nine prospective, placebo-controlled planned clinical trials of similar design. Six studies (958 patients) enrolled patients with seasonal allergic rhinitis and concomitant asthma; three (607 patients) involved patients with persistent asthma. In all studies, patients were excluded from oral corticosteroid therapy in the preceding 3 months, and from inhaled corticosteroids in the preceding month.

RESULTS

Patients with seasonal rhinitis and asthma had a significantly (P<0.001) higher total asthma symptom score than those with persistent asthma. In particular, cough was three times more severe. The need for beta(2)-agonist as a rescue medication and the ratio of forced expiratory volume in 1 s/forced vital capacity (FVC) were similar in the two groups whereas forced expiratory fraction 25-75%/FVC was significantly (P<0.02) reduced in the persistent asthmatics. Asthma and nasal symptom severity scores were correlated in patients with seasonal rhinitis and asthma (P<0.0001).

CONCLUSIONS

Patients with seasonal allergic rhinitis and concomitant asthma appear to differ from those with persistent asthma. A prospective study should be designed to discover whether patients with seasonal rhinitis and asthma may represent a distinct nosological entity, 'allergic airway disease'.

Clinical efficacy of sublingual and subcutaneous birch pollen allergen-specific immunotherapy: a randomized, placebo-controlled, double-blind, double-dummy study

BACKGROUND

Both sublingual allergen-specific immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT) have a documented clinical efficacy, but only few comparative studies have been performed.

OBJECTIVE

To investigate the clinical efficacy of SLIT vs SCIT and secondary to compare SLIT and SCIT with placebo and to evaluate the relative clinical efficacy in relation to systemic side-effects.

METHODS

A 3-year randomized, placebo-controlled, double-blind, double-dummy study including 71 adult birch pollen hay fever patients treated for two consecutive years after a baseline year. Allocation to treatment groups was based on disease severity in the baseline season, gender and age.

RESULTS

Clinical efficacy was estimated in 58 patients completing the first treatment year by subtracting baseline data and by calculating the ratio first treatment season vs baseline. SLIT diminished the median disease severity to one-half and SCIT to one-third of placebo treatment. No statistical significant difference between the two groups was observed. Both for symptoms and medication scores actively treated patients showed statistically significant and clinical relevant efficacy compared with placebo. SLIT treatment only resulted in local mild side-effects, while SCIT resulted in few serious systemic side-effects.

CONCLUSION

Based on the limited number of patients the clinical efficacy of SLIT was not statistically different from SCIT, and both treatments are clinically effective compared with placebo in the treatment of birch pollen rhinoconjunctivitis. The lack of significant difference between the two treatments does not indicate equivalent efficacy, but to detect minor differences necessitates investigation of larger groups. Due to the advantageous safety profile SLIT may be favored.

The impact of rhinosinusitis on asthma

The nasal cavity, paranasal sinuses, and lungs are considered separate organs of the respiratory tract. However, a growing body of evidence links the upper and lower airways. For example, the coexistence and impact of allergic and nonallergic rhinitis on asthma is now documented. In addition, inflammation of the nose (rhinitis) commonly is associated with inflammation of sinuses (sinusitis), as reflected in the term rhinosinusitis. In this paper, we review the impact of rhinosinusitis on asthma as it relates to the links between allergic and nonallergic rhinitis and asthma; viral upper respiratory tract infections and asthma; allergic and nonallergic infectious/inflammatory rhinosinusitis and allergic and nonallergic hyperplastic rhinosinusitis and asthma; and the aspirin-exacerbated respiratory disease syndrome and asthma.

Immunological mechanisms in specific immunotherapy

Specific immunotherapy (SIT) represents the only curative treatment of allergy and is, therefore, of particular interest for immunological and pharmacological research. The current understanding of immunological mechanisms underlying SIT focuses on regulatory T cells (T regs), which balance Th1 and Th2 effector functions. This ensures that allergens are recognized, but tolerated by the immune system. There is clear evidence that SIT restores the disturbed balance of T regs and effector cells in allergic patients. Current efforts are focused to improve SIT regimens to make them more applicable in atopy and asthma. The current review provides an overview on the mechanisms of SIT and possible adjuvant treatment strategies on the background of the T reg concept.

Immunotherapy for rhinitis

Allergen-specific immunotherapy in the treatment of allergic rhinitis has a well-documented clinical efficacy that indicates a statistically significant and clinically relevant reduction in symptom scores and the need for pharmacotherapy. The clinical efficacy of recently published studies is equivalent to or superior to the effect of standard anti-allergic drugs. Additional advantages are related to a downregulation of the allergic phenotype with the additional induction of a Th1 cytokine profile. The immunoregulatory capacity and the global downregulation of the allergic inflammation in mucous membranes might be important factors in the capacity to ensure long-term clinical efficacy (after termination of treatment) and the preventive capacity of immunotherapy in reducing the progression of rhinitis to asthma as well as deflowering the development of new sensitizations. Subcutaneous immunotherapy is optimal in severe allergic rhinitis with signs of bronchial hyperreactivity; however, sublingual immunotherapy might be an option for patients with milder disease.

Advances in upper airway diseases and allergen immunotherapy

Epidemiologic studies continue to find an increased prevalence of rhinitis, asthma, and atopy in more westernized countries. Both allergic and nonallergic rhinitis are risk factors for development of asthma, particularly in adulthood. In patients who have both asthma and rhinitis, treatment of the latter decreases the likelihood of emergency department visits or hospitalization for asthma. The protective effect of intranasal cortico-steroids is much greater than that of antihistamines. This mirrors the effect on rhinitis symptoms, in which nasal corticosteroids are much more effective than antihistamines, leukotriene receptor antagonists, or the combination of both. In patients with severe asthma, sinus mucosal thickening on computed tomography (CT) correlates with the severity of lower airway disease indicated by sputum eosinophilia, exhaled nitrous oxide (NO), functional residual capacity, and diffusing capacity. Preseasonal specific immunotherapy (SIT) is less effective, but additive to treatment with omalizumab. It is also somewhat less effective in reducing nasal symptoms than nasal corticosteroids; however, it is superior to them for reducing lower airway inflammation. SIT in children with only allergic rhinitis reduces both the incidence of asthma and bronchial hyperresponsiveness to methacholine. High-dose sublingual immunotherapy appears to be safe and effective, but less effective than injection immunotherapy. It is not clear that there are cost savings with sublingual immunotherapy, as home administration savings may be offset by the much larger amount of allergen extracts required. New approaches to allergen immunotherapy, designed to increase efficacy and safety, include conjugation of allergens to immunostimulatory sequences and encapsulation in liposomes. Cross-reactivity between inhalants and foods demonstrated by skin prick tests is more predictive of clinically important sensitivity than is that demonstrated by RAST testing. The latter, because of cross-reacting profilins, is often clinically irrelevant.

Intranasal corticosteroids for asthma control in people with coexisting asthma and rhinitis

BACKGROUND

Allergic rhinitis and asthma are mediated by similar allergic mechanisms. They may represent two manifestations of the same united airway disease and therefore intranasal corticosteroids (INCS) could improve asthma. Nevertheless none of the asthma guidelines have advocated intranasal corticosteroids for asthma.

OBJECTIVES

To assess the efficacy of intranasal corticosteroids on asthma outcomes in people with rhinitis and asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group trials register, the Cochrane Central Register of Controlled Trials (Issue 1, 2003), MEDLINE and reference lists of articles. We also contacted researchers in the field. Last search updated in March 2003.

SELECTION CRITERIA

Randomised controlled trials comparing intranasal corticosteroids to intranasal placebo or to other traditional asthma treatments were included. Intrabronchial corticosteroids were not allowed but a device combining intranasal and intrabronchial corticosteroid was considered as being a primary INCS technique and was therefore also compared to placebo.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. Quality assessment for the 14 eligible studies was performed using the Jadad score and by ranking allocation concealment. Statistical analysis for continuous data was done by weighted mean difference or standardised mean difference.

MAIN RESULTS

Fourteen trials involving 477 people were included. Meta-analysis for asthma outcomes failed to show a statistically significant benefit of INCS in asthma. However, for symptom scores and forced expiratory volume in one second, the trend favoured a beneficial effect of INCS. For asthma symptom scores (two parallel studies), the standardised mean difference was 0.61 (95% confidence interval (CI) -0.04 to 1.26). Meta-analysis for forced expiratory volume in one second (five parallel studies) gave a standardised mean difference of 0.31 (95% CI -0.04 to 0.65). In the parallel studies, meta-analysis of peak expiratory flow gave a standardised mean difference of -0.10 Litres/min (95% CI -0.55 to 0.35) for mean peak flow (three studies). Meta-analysis for methacholine airway responsiveness (three parallel studies) showed a standardised mean difference of -0.20 (-95% CI 0.64 to 0.24).

REVIEWER'S CONCLUSIONS

Intranasal corticosteroids were well tolerated. While INCS tended to improve asthma symptoms and forced expiratory volume in one second, the results did not reach significance. The combination of intranasal plus intrabronchial corticosteroids should remain the current clinical practice until more research is done.