Recommendations for standardization of clinical trials with Allergen Specific Immunotherapy for respiratory allergy. A statement of a World Allergy Organization (WAO) taskforce

Long-term efficacy of specific immunotherapy on house dust mite-induced allergic rhinitis in China

OBJECTIVE

Although the effect of specific immunotherapy (SIT) on allergic rhinitis (AR) has been well documented in developed countries, its long-term efficacy in patients in developing countries (such as China) is poorly understood. This study investigated the long-term therapeutic and preventive effects of SIT on house dust mite (HDM)-induced AR in patients from China.

DESIGN

Historical cohort study.

SETTING

University hospital.

SUBJECTS AND METHODS

One hundred forty-six AR patients with/without asthma allergic to HDM were investigated for 5 years after initiation of a 3-year course of subcutaneous SIT (SIT group, n = 106) or no SIT (control group, n = 40). The clinical responses of all patients were evaluated at baseline, the stop point of SIT (third year), and 2 years after SIT termination (fifth year), by clinical index including symptom and rescue medication scores (SMS), visual analog scale (VAS), total immunoglobulin E (tIgE), and specific IgE (sIgE). Asthma was assessed by clinical evaluation.

RESULTS

The decrease of SMS and VAS from baseline was significantly improved in the SIT group compared with controls at both the third and fifth year. For patients without asthma at baseline, the odds ratio for no asthma was 3.57 (95% confidence interval, 1.05-12.91; P < .05) in favor of SIT. The serum sIgE/tIgE ratio was significantly increased after SIT treatment in the SIT group, but it was not related to SIT efficacy.

CONCLUSION

SIT has a long-term effect of improving clinical symptoms and reducing the risk of development of asthma in Chinese AR patients.

Subcutaneous and sublingual immunotherapy for seasonal allergic rhinitis: a systematic review and indirect comparison

BACKGROUND

Severe allergic rhinitis uncontrolled by pharmacotherapy can adversely affect quality of life. Both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) have demonstrated effectiveness in this patient group; however, it remains uncertain which route of administration is more effective.

OBJECTIVES

We sought to update existing systematic reviews on the clinical effectiveness of SCIT and SLIT versus placebo, to undertake a systematic review of head-to-head trials, and to compare the relative effectiveness of SCIT and SLIT in an adjusted indirect comparison.

METHODS

Standard systematic review methods aimed at minimizing bias were used. Double-blind, randomized, placebo-controlled trials of SCIT or SLIT or trials of SCIT versus SLIT were included. Meta-analysis and indirect comparison meta-analysis with meta-regression were performed.

RESULTS

Updated meta-analyses confirmed statistically significant benefits for SCIT and SLIT compared with placebo in adults and, to a lesser extent, in children. Only 1 head-to-head trial met the inclusion criteria; both this and the indirect comparisons did not provide conclusive results in favor of either SCIT or SLIT based on symptom-medication or quality-of-life scores. There was a trend toward favoring SCIT for symptom and medication scores.

CONCLUSIONS

Although there is clear evidence of effectiveness of both SCIT and SLIT, superiority of one mode of administration over the other could not be consistently demonstrated through indirect comparison, and further research is needed to establish the comparative effectiveness of SCIT versus SLIT.

Sublingual immunotherapy for allergic rhinitis and conjunctivitis

Sublingual immunotherapy (SLIT) for allergic respiratory diseases was first described in 1986 and immediately appeared as a viable alternative to the traditional subcutaneous route. Since then, more than 60 randomized controlled trials have been published, almost all with very favorable results. The average improvement over placebo in symptom score and medication use was always greater than 20%. The results of the clinical trials were pooled in several meta-analyses, which consistently confirmed the efficacy of the treatment. SLIT is characterized by a satisfactory safety profile, its side effects being mainly limited to oral discomfort. Only six anaphylaxes and no fatalities have been so far reported. Due to the good risk:benefit ratio, SLIT is currently being investigated in diseases other than respiratory allergy, such as food allergy and atopic dermatitis.

The paucity of ethical analysis in allergology

While a growing body of research is uncovering the aetiology and effective treatments for allergy, research that assess the broader ethical implications of this disease is lacking significantly. This article will demonstrate both the paucity of academic research concerning ethical implications in allergy and explain why ethical analysis is integral to formulating effective health strategies for allergic disease. An exhaustive literature search of publications in French and English identified less than 35 academic articles focussed on the topic of ethics and allergy; this is a miniscule number when compared to the amount of articles published on ethical issues related to other chronic illnesses, such as obesity. It is important to demonstrate to allergy specialists the need for, and utility of, further incorporating ethical analyses in allergology; the current success of Ethical, Legal, Social Implications (ELSI) research programmes in human genetics and nanotechnology will serve as notable examples. Indeed, future research and innovation in allergy will undoubtedly encounter ethical dilemmas and the allergology community should play a significant role in helping to address these issues. However, incorporating ethical analyses in allergology does not imply that the allergology community must acquire extensive knowledge in bioethics; instead, interdisciplinary research that incorporates expertise from allergology and bioethics would enable allergy specialists to advance critical knowledge development in this largely overlooked domain of study.

The relevance of patient-reported outcomes in a grass pollen immunotherapy trial in children and adolescents with rhinoconjunctivitis

BACKGROUND

Patient-reported outcomes (PROs) are the only instruments available to assess the efficacy of an intervention in patients with allergic rhinoconjunctivitis. As allergic rhinoconjunctivitis is a systemic disease, it is now recommended to use not only PROs focusing at classical symptoms, but also health-related quality of life (HRQL) instruments in immunotherapy trials.

METHODS

A previously published immunotherapy trial in children and adolescents (6-18 yr) with hay fever provided us with data to assess the relevance of two of these additional outcome measures, the disease-specific rhinoconjunctivitis quality of life questionnaire (RQLQ) and the generic COOP/WONCA-charts (CWC). A PRO was considered relevant if it was responsive to pollen exposure and at least had a moderate correlation with the classical symptoms of allergic rhinoconjunctivitis. Furthermore, we evaluated a post-season PRO, that is, a global assessment of symptoms (GAS). This assessment is used in clinical trials as a tool for selecting participants with sufficient symptoms and in daily practice to evaluate the patient's complaints during the preceding season. We assessed the correlation of this retrospective score with the actual symptoms during the previous pollen season.

RESULTS

Data from 36 children and 63 adolescents were analysed. On the basis of the total scores of the paediatric and adolescent version of the RQLQ, both questionnaires were considered relevant as they were responsive to exposure and showed a moderate to strong correlation with the rhinoconjunctivitis symptoms. However, in both children and adolescents, 40% of the RQLQ items were not relevant according to our definition. The CWC as a whole and the separate charts appear less relevant because of the weak correlations with the daily symptom score from the diary. The correlation between our post-season GAS and the in season daily symptom score was weak.

CONCLUSION

The paediatric and adolescent RQLQ are relevant, but could be shortened as they contain a substantial number of irrelevant items. The CWC are not relevant in the monitoring of children and adolescents with allergic rhinoconjunctivitis caused by grass pollen. The retrospective GAS does not sufficiently reflect the actual symptoms during the preceding season.

Comparison of the long-term efficacy of 3- and 5-year house dust mite allergen immunotherapy

BACKGROUND

The recommended duration of specific immunotherapy (SIT) treatment relies on empiric data and is not well documented.

OBJECTIVE

To detect possible differences in the long-term effectiveness between 3 and 5 years of house dust mite (HDM) SIT in asthmatic children.

METHODS

We performed a 3-year natural history study of 90 asthmatic children who were sensitive only to HDM. Three groups were recruited: 30 who had completed 3 years of HDM SIT (SIT3), 30 who had completed 5 years of HDM SIT (SIT5), and 30 who had an indication for HDM SIT but whose parents refused HDM SIT. Patients attended an enrollment visit in 2007, after SIT discontinuation, and 3 annual follow-up visits at the clinic. The long-term effectiveness of HDM SIT was primarily assessed via analysis of the reduction in required inhaled corticosteroid dose, forced expiratory volume in 1 second, and asthma remission.

RESULTS

A total of 84 children completed the study. Both SIT durations produced excellent results; asthma remission in both SIT3 (50%) and SIT5 (54%) groups was significantly higher when compared with control (3.3%). The minimal controlling inhaled corticosteroid dose reduction in SIT5 group (median, 75%) was significantly higher compared with the SIT3 group (median, 50%) after immunotherapy discontinuation; after 3 years without SIT, no differences were found between the SIT5 and SIT3 groups (median, 100% and 94%, respectively). We observed a slightly higher increase in forced expiratory volume in 1 second in the SIT5 group compared with the SIT3 group.

CONCLUSION

Three years of SIT is an adequate duration for the treatment of childhood asthma associated with HDM allergy because 2 further years of SIT added no clinical benefit.

Subcutaneous allergen immunotherapy for allergic disease: examining efficacy, safety and cost-effectiveness of current and novel formulations

Subcutaneous immunotherapy (SCIT) is a unique therapy for allergic disease because it provides symptomatic relief while modifying the allergic disease by targeting the underlying immunological mechanism. Its efficacy and safety have been established in the treatment of asthma, allergic rhinitis/rhinoconjunctivitis and stinging insect hypersensitivity in numerous controlled clinical trials. This review evaluates a spectrum of clinical factors, ranging from efficacy to cost-effectiveness, which should be considered in evaluating SCIT. The evidence for SCIT safety and efficacy for these conditions is reviewed in an evaluation of the systematic reviews and meta-analyses. The evidence for the persistent and preventive effects of SCIT is also examined. An overview of the SCIT outcomes measures utilized in clinical trials is presented. The cost-effectiveness of SCIT compared with conventional medication treatment, novel indications and formulations for SCIT are also explored in this review.

Efficacy of subcutaneous and sublingual immunotherapy with grass allergens for seasonal allergic rhinitis: a meta-analysis-based comparison

BACKGROUND

Subcutaneous (SCIT) and sublingual (SLIT) immunotherapy are the 2 most prescribed routes for administering allergen-specific immunotherapy. They were shown to be effective in control of symptoms and in reducing rescue medication use in patients with allergic diseases, but their effectiveness has to be balanced against side effects. In recent years, SLIT has been increasingly prescribed, instead of SCIT, because of improved safety and easy administration.

OBJECTIVE

We assessed which route is the most effective in the treatment of patients with seasonal allergic rhinitis to grass pollen.

METHODS

An indirect meta-analysis-based comparison between SCIT and SLIT was performed. Treatment efficacy was determined as the standardized mean difference (SMD) in symptom and medication scores obtained with active treatment, SCIT or SLIT, compared with placebo. Studies were included if they were double-blind randomized controlled trials comparing SCIT or SLIT with placebo. Thirty-six randomized controlled trials (3014 patients; 2768 controls) were analyzed.

RESULTS

The overall effect size of SCIT for symptom score (SMD, -0.92; 95%CI, -1.26 to -0.58) was significantly higher than SLIT, both administered via drops (SMD, -0.25; 95% CI, -0.45 to -0.05) and tablets (SMD, -0.40; 95%CI, -0.54 to -0.27). Similar results were reported for medication score (SCIT: SMD, -0.58; 95% CI, -0.86 to -0.30. SLIT drops: SMD, -0.37; 95% CI, -0.74 to -0.00. SLIT tablets SMD, -0.30; 95% CI, -0.44 to -0.16).

CONCLUSIONS

Our results provide indirect but solid evidence that SCIT is more effective than SLIT in controlling symptoms and in reducing the use of antiallergic medications in seasonal allergic rhinoconjuntivitis to grass pollen.

Prospective validation of the "rhino conjunctivitis allergy-control-SCORE©" (RC-ACS©)

Background

Recently we reported the validation of the “Allergy-Control-SCORE^© (ACS)” which assesses symptom severity as well as medication use on three dimensions lung, nose and eyes. The aim of this study was to test the validity of the score for eyes and nose.

Methods

One-hundred-twenty-one consenting subjects (age 19-65y), including 81 patients with allergic rhino-conjunctivitis (RC) and 40 healthy controls, participated in the study. Patients rated daily nasal and eye symptoms using a 4-point scale (none, mild, moderate, and severe) and their use of anti-symptomatic medication. Validation criteria were pollen counts in the course of the study period. Discrimination capacity was analyzed by comparing the rhino-conjunctivitis Allergy-Control-SCORE^© (RC-ACS^©) values of allergic patients and healthy controls. Convergent reliability was assessed by correlating RC-ACS^© values with the global severity of allergy, the quality of life, and the allergy-related medical consultations. Retest reliability was assessed by the correlation of the repeated measured RC-ACS^© scores during each of two consecutive weeks.

Results

Convergent reliability analysis indicated a significant correlation between RC-Allergy-Control-SCORE^© and global severity of allergy (r = 0.691; p < 0.0001), quality of life (r = 0.757; p < 0.0001) and allergy-related medical consultations (r = 0.329; p = 0.0019). RC-Allergy-Control-SCORE^© showed a good retest reliability (r = 0.813; p < 0.001) and discriminated extremely well between allergic patients and healthy controls (Median: 3.7 range: 0; 14.1 vs. Median: 0 range: 0; 2.9; p < 0.001), with a sensitivity of 93.8% and a specificity of 92.5% at a score value of 0.786.

Conclusions

The RC-ACS^© can be considered as valid and reliable to assess the severity of rhino-conjunctivitis severity in clinical trials and observational studies.

High-dose sublingual immunotherapy with single-dose aqueous grass pollen extract in children is effective and safe: a double-blind, placebo-controlled study

BACKGROUND

Sublingual allergen-specific immunotherapy is a viable alternative to subcutaneous immunotherapy particularly attractive for use in children.

OBJECTIVE

This study investigated efficacy and safety of high-dose sublingual immunotherapy (SLIT) in children allergic to grass pollen in a randomized, double-blind, placebo-controlled trial.

METHODS

After a baseline seasonal observation, 207 children aged 4 to 12 years with grass pollen-allergic rhinitis/rhinoconjunctivitis with/without bronchial asthma (Global Initiative for Asthma I/II) received either high-dose grass pollen SLIT or placebo daily for 1 pre-/co-seasonal period. The primary end point was the change of the area under the curve of the symptom-medication score (SMS) from the baseline season to the first season after start of treatment. Secondary outcomes were well days, responders, immunologic changes, and safety.

RESULTS

Mean changes in the area under the curve of the SMS from the baseline to the first grass pollen season after the start of treatment were -212.5 for the active group and -97.8 for the placebo group (P = .0040). Rhinoconjunctivitis SMS (P = .0020) and separated symptom and medication scores were also statistically different between the 2 groups (P = .0121 and P = .0226, respectively). The number of well days and the percentage of responders were greater in the active group. Changes in allergen-specific IgE and IgG levels indicated a significant immunologic effect. The treatment was well tolerated, and no serious treatment-related events were reported.

CONCLUSIONS

This study confirmed that this SLIT preparation significantly reduced symptoms and medication use in children with grass pollen-allergic rhinoconjunctivitis. The preparation showed significant effects on allergen-specific antibodies, was well tolerated, and appeared to be a valid therapeutic option in children allergic to grass pollen. This trial was registered at www.clinicaltrials.gov as NCT00841256.

Allergic Rhinitis and Its Impact on Asthma in Asia Pacific and the ARIA Update 2008

The prevalence of allergic diseases such as allergic rhinitis (AR) and asthma are markedly increasing to epidemic proportions worldwide as societies adopt Western lifestyles. An estimated 300 million persons worldwide have asthma, about 50% of whom live in developing countries, and about 400 million people suffer from AR. AR has a marked impact on quality of life, socially, at school, and in the workplace and is a huge socioeconomic burden. Thus, there was clearly a need for a global evidence-based guideline not only for managing AR but also highlighting the interactions between the upper and lower airways including diagnosis, epidemiology, common risk factors, management, and prevention. The Allergic Rhinitis and its Impact on Asthma (ARIA) document was first published in 2001 as a state-of-the-art document for the specialist, the general practitioner, and other health care professionals. Subsequent research and increasing knowledge have resulted in the ARIA 2008 update. The present review summarizes the ARIA update with particular emphasis on the current status of AR and asthma in Asia Pacific.

Allergen-specific immunotherapy provides immediate, long-term and preventive clinical effects in children and adults: the effects of immunotherapy can be categorised by level of benefit -the centenary of allergen specific subcutaneous immunotherapy

Allergen Specific Immunotherapy (SIT) for respiratory allergic diseases is able to significantly improve symptoms as well as reduce the need for symptomatic medication, but SIT also has the capacity for long-term clinical effects and plays a protective role against the development of further allergies and symptoms. The treatment acts on basic immunological mechanisms, and has the potential to change the pathological allergic immune response. In this paper we discuss some of the most important achievements in the documentation of the benefits of immunotherapy, over the last 2 decades, which have marked a period of extensive research on the clinical effects and immunological background of the mechanisms involved. The outcome of immunotherapy is described as different levels of benefit from early reduction in symptoms over progressive clinical effects during treatment to long-term effects after discontinuation of the treatment and prevention of asthma. The efficacy of SIT increases the longer it is continued and immunological changes lead to potential long-term benefits. SIT alone and not the symptomatic treatment nor other avoidance measures has so far been documented as the therapy with long-term or preventive potential. The allergic condition is driven by a subset of T-helper lymphocytes (Th2), which are characterised by the production of cytokines like IL-4, and IL-5. Immunological changes following SIT lead to potential curative effects. One mechanism whereby immunotherapy suppresses the allergic response is through increased production of IgG4 antibodies. Induction of specific IgG4 is able to influence the allergic response in different ways and is related to immunological effector mechanisms, also responsible for the reduced late phase hyperreactivity and ongoing allergic inflammation. SIT is the only treatment which interferes with the basic pathophysiological mechanisms of the allergic disease, thereby creating the potential for changes in the long-term prognosis of respiratory allergy. SIT should not only be recognised as first-line therapeutic treatment for allergic rhinoconjunctivitis but also as secondary preventive treatment for respiratory allergic diseases.

Intralymphatic immunotherapy for cat allergy induces tolerance after only 3 injections

BACKGROUND

Subcutaneous allergen-specific immunotherapy frequently causes allergic side effects and requires 30 to 80 injections over 3 to 5 years.

OBJECTIVE

We sought to improve immunotherapy by using intralymphatic allergen administration (intralymphatic immunotherapy [ILIT]) and by targeting allergen to the MHC class II pathway.

METHODS

Recombinant major cat dander allergen Fel d 1 was fused to a translocation sequence (TAT) and to part of the human invariant chain, generating a modular antigen transporter (MAT) vaccine (MAT-Fel d 1). In a randomized double-blind trial ILIT with MAT-Fel d 1 in alum was compared with ILIT with placebo (saline in alum) in allergic patients (ClinicalTrials.govNCT00718679).

RESULTS

ILIT with MAT-Fel d 1 elicited no adverse events. After 3 placebo injections within 2 months, nasal tolerance increased less than 3-fold, whereas 3 intralymphatic injections with MAT-Fel d 1 increased nasal tolerance 74-fold (P < .001 vs placebo). ILIT with MAT-Fel d 1 stimulated regulatory T-cell responses (P = .026 vs placebo) and increased cat dander-specific IgG(4) levels by 5.66-fold (P = .003). The IgG(4) response positively correlated with IL-10 production (P < .001).

CONCLUSION

In a first-in-human clinical study ILIT with MAT-Fel d 1 was safe and induced allergen tolerance after 3 injections.

Sublingual immunotherapy not effective in house dust mite-allergic children in primary care

BACKGROUND

Sublingual immunotherapy (SLIT) as a therapy for the treatment of allergic rhinitis in children might be acceptable as an alternative for subcutaneous immunotherapy. However, the efficacy of SLIT with house dust mite extract is not well established.

OBJECTIVE

To investigate whether SLIT in house dust mite-allergic children recruited in primary care is effective and safe.

METHODS

Children aged 6-18 years (n = 251) recruited in primary care with a house dust mite-induced allergic rhinitis received either SLIT or placebo for 2 years. Symptoms and medication use were assessed throughout the study. Primary outcome parameter was the mean total nose symptom score (scales 0-12) during the autumn of the second treatment year. Safety was assessed by recording any adverse event.

RESULTS

Overall, the mean nose symptom score ± s.d. after 2 years of treatment showed no significant effect of SLIT (symptom score intervention group 2.26 ± 1.84 vs. placebo group, 2.02 ± 1.67; p = 0.08). There were no significant differences in secondary outcomes, nor in subgroup analyses. The number of patients reporting adverse events was comparable between both groups.

CONCLUSIONS

Sublingual immunotherapy with house dust mite allergen was not better than placebo in reducing rhinitis symptoms in house dust mite-allergic children in primary care. SLIT as administered in this study can be considered safe.

Sublingual allergen immunotherapy: mode of action and its relationship with the safety profile

Allergen immunotherapy reorients inappropriate immune responses in allergic patients. Sublingual allergen immunotherapy (SLIT) has been approved, notably in the European Union, as an effective alternative to subcutaneous allergen immunotherapy (SCIT) for allergic rhinitis patients. Compared with SCIT, SLIT has a better safety profile. This is possibly because oral antigen-presenting cells (mostly Langerhans and myeloid dendritic cells) exhibit a tolerogenic phenotype, despite constant exposure to danger signals from food and microbes. This reduces the induction of pro-inflammatory immune responses leading to systemic allergic reactions. Oral tissues contain relatively few mast cells and eosinophils (mostly located in submucosal areas) and, in comparison with subcutaneous tissue, are less likely to give rise to anaphylactic reactions. SLIT-associated immune responses include the induction of circulating, allergen-specific Th1 and regulatory CD4+ T cells, leading to clinical tolerance. Although 40-75% of patients receiving SLIT experience mild, transient local reactions in the oral mucosa, these primary reactions rarely necessitate dose reduction or treatment interruption. We discuss 11 published case reports of anaphylaxis (all nonfatal) diagnosed according to the World Allergy Organization criteria and relate this figure to the approximately 1 billion SLIT doses administered worldwide since 2000. Anaphylaxis risk factors associated with SCIT and/or SLIT should be characterized further.

Analysis of allergen immunotherapy studies shows increased clinical efficacy in highly symptomatic patients

BACKGROUND

The assessment of allergen immunotherapy (AIT) efficacy in the treatment for seasonal allergic rhinoconjunctivitis (SAR) symptoms is challenging. Allergen immunotherapy differs from symptomatic therapy in that while symptomatic therapy treats patients after symptoms appear and aims to reduce symptoms, AIT is administered before symptoms are present and aims to prevent them. Thus, clinical studies of AIT can neither establish baseline symptom levels nor limit the enrolment of patients to those with the most severe symptoms. Allergen immunotherapy treatment effects are therefore diluted by patients with low symptoms for a particular pollen season. The objective of this analysis was to assess the effect possible to achieve with AIT in the groups of patients presenting the most severe allergic symptoms.

METHODS

Study centres were grouped into tertiles categorized according to symptom severity scores observed in the placebo patients in each centre (low, middle and high tertiles). The difference observed in the average score in each tertile in active vs placebo-treated patients was assessed. This allowed an estimation of the efficacy that could be achieved in patients from sites where symptoms were high during the pollen season.

RESULTS

An increased treatment effect was observed in the most severe patients and was independent of the study analysed and symptom score used.

CONCLUSIONS

The use of a tertile approach to analyse efficacy in AIT in SAR clinical studies can give a more accurate assessment of potential clinical benefit.

Long-term clinical and immunological effects of allergen immunotherapy

PURPOSE OF REVIEW

The present review updates current findings on long-term clinical and immunological outcomes after cessation of allergen immunotherapy for allergic respiratory disease.

RECENT FINDINGS

Recent studies have shown that allergen immunotherapy has sustained disease-modifying effects that persist for years after discontinuation. This is in contrast to the effects of antiallergic drugs that do not induce tolerance to offending allergens. Long-term effects of immunotherapy include a reduction in nasal symptoms, a decrease in the use of rescue medication and improvement in quality of life. These benefits are accompanied by immunological changes such as the induction of allergen-specific IgG antibodies with inhibitory activity for IgE-facilitated binding of allergen-IgE complexes to B cells. One study reported a reduction in the development of asthma in children with seasonal pollen-induced rhinitis.

SUMMARY

Allergen immunotherapy induces clinical and immunological tolerance as defined by persistence of clinical benefit and associated long-term immunological parameters after discontinuation of treatment. These findings are largely confined to studies of subcutaneous and sublingual immunotherapy for seasonal pollinosis. Further studies are needed to address potential long-term clinical effects for other seasonal and perennial inhaled allergens in both children and adults, and to identify potential biomarkers of tolerance.

Allergen-specific immunotherapy with recombinant allergens

Subcutaneous immunotherapy is a well-documented treatment of allergic rhinitis and asthma. The major limitation is the risk of anaphylactic side effects. The documentation of clinical efficacy is based on crude allergenic extracts sometimes containing varying amounts of individual allergens including allergens to which the patient may not be sensitized. The introduction of recombinant allergens offer a possibility to use well-defined molecules with consistent pharmaceutical quality defined in mass units. The proof-of-concept of the clinical efficacy of recombinant allergens is based on two studies published as full articles. One study applied a mixture of five Phleum pratense major allergens in a maximum dose of 40 μg protein. The clinical efficacy showed a significant efficacy with about 40% reduction in disease severity. The second study compared a commercial birch extract with both recombinant Bet v 1 and purified Bet v 1 in dosages of 15 μg allergen. The clinical effect was around 60% additional efficacy. Systemic side effects occurred more frequently with grass allergens. A third study used hypoallergenic fragments and a trimer of Bet v 1. The study did not show efficacy and a rather high frequency of systemic side effects. The advantages of using recombinant allergens for immunotherapy are obvious but more large-scale clinical studies are needed before the overall value in terms of efficacy and safety can be determined.

A randomized placebo-controlled trial of rush preseasonal depigmented polymerized grass pollen immunotherapy

BACKGROUND

Specific subcutaneous immunotherapy (SCIT) for seasonal rhinoconjunctivitis with unmodified allergen extracts is effective, but limited by risk of side-effects and involves treatment over 3 years. We examined a depigmented polymerized grass pollen extract for immunogenicity and for clinical efficacy in a rush preseasonal regimen.

METHODS

Depigmented polymerized grass pollen extract was tested for proliferation and cytokine production by peripheral blood mononuclear cells. A prospective, double-blind, placebo-controlled trial of 195 grass pollen allergic patients treated with preseasonal rush immunotherapy using depigmented polymerized allergenic extract of mixed grass pollen was performed over 2 years. Primary outcome was combined symptom and medication score (SMS) during the peak of the second grass pollen season. Secondary outcomes included combined score over the whole season, during the first grass pollen season, individual symptom and medication scores, quality of life, well days/hell days and responder analysis. Adverse events were classified using the EAACI scale. Grass pollen-specific IgE and IgG4 were measured before and during treatment.

RESULTS

Depigmented polymerized extract stimulated dose-dependent T-cell proliferation and cytokine production. Patients treated with preseasonal SCIT showed improved combined scores during peak season at year 2 (median 3.93, interquartile range 0.77-6.27 vs median 5.86 for placebo, 3.11-8.36, P < 0.01). Most secondary outcomes were significantly better for active treatment. Side-effects were minimal, with no grade 3 or 4 reactions.

CONCLUSIONS

Depigmented polymerized grass pollen extract is immunogenic and clinically effective in rush preseasonal SCIT. This form of immunotherapy may be an attractive option for some patients.

Difference in symptom severity between early and late grass pollen season in patients with seasonal allergic rhinitis

BACKGROUND

For the development of forecasts for seasonal allergic rhinitis symptoms, it is essential to understand the relationship between grass pollen concentrations and the symptoms of grass pollen allergic patients.

OBJECTIVE

The aim of this study was to delineate this relationship between seasonal allergic rhinitis symptoms and grass pollen concentrations in the Netherlands.

METHODS

Grass pollen allergic patients (n = 80 [2007] - 84 [2008]) were enrolled into the study. They were asked to enter their seasonal allergic rhinitis symptoms (runny nose, sneezing, blocked nose, post nasal drip, and eye symptoms) daily on a scale from 0 to 3 to the study centre either by short message service (SMS) or by internet from May-July 2007 and April-July 2008. Daily pollen counts were used to define the early and the late grass pollen season as the period 'before and during' respectively 'after' the first grass pollen peak (more than 150 pollen/m3).

RESULTS

At similar grass pollen concentrations, the daily mean of the individual maximum symptom scores reported in the early season were higher as compared to that reported in the late season [differences of -0.41 (2007) and -0.30 (2008)]. This difference could not be explained by medication use by the patients nor by co-sensitization to birch.

CONCLUSIONS

We conclude that seasonal allergic rhinitis symptoms at similar grass pollen concentrations are more severe in the early flowering season as compared to those in the late flowering season. This finding is not only relevant for development of forecasts for seasonal allergic rhinitis symptoms but also for understanding symptom development and planning and analysis of clinical studies.

Direct comparison between continuous and coseasonal regimen for sublingual immunotherapy in children with grass allergy: a randomized controlled study

BACKGROUND

Pre-seasonal, pre-coseasonal and continuous regimens of immunotherapy have been proposed, but their efficacy was never compared. This phase IV open study was designed to compare the clinical efficacy of a continuous and a coseasonal sublingual immunotherapy (SLIT) for grass allergy over 3 years.

METHODS

Children with rhinitis/asthma because of grass were randomized to SLIT given continuously (all year long) or coseasonally. The treatment started in October 2005 in the continuous SLIT group and in March 2006 in the coseasonal group Diary cards for clinical symptoms (from 0 = none to 3 = severe), and drug intake were recorded form March to June in 2005 (baseline), 2006 2007, and 2008. Specific IgE and IgG4 were evaluated every year.

RESULTS

Eighty children (age range 8-16) were randomized and 72 completed the study. In the first year, the symptom + medication score improved by 44% in the continuous group and by 20% in the coseasonal group (p = 0.04). Symptoms, chest symptoms, and drug intake separately showed a greater decrease vs. baseline in the continuous group. In the second year, the global score decreased in both groups with no significant difference, whereas symptom score decreased more in the continuous group. In the 3rd year, there was no difference in clinical parameters between the two groups. Specific IgG4 were significantly higher vs. baseline since the 1st year in the continuous group and since the 2nd in the coseasonal group.

CONCLUSION

In grass pollen allergy, the continuous regimen performs better than the coseasonal in the first season, whereas in the subsequent years, the two regimens are nearly equivalent.

Design and recruitment for the GAP trial, investigating the preventive effect on asthma development of an SQ-standardized grass allergy immunotherapy tablet in children with grass pollen-induced allergic rhinoconjunctivitis

BACKGROUND

Allergic rhinoconjunctivitis is a risk factor for asthma development. Treating the underlying allergy may represent an attractive method of asthma prevention. No regulatory guidance exists in this area, and, to our knowledge, no clinical investigations meeting modern regulatory standards have been published.

OBJECTIVE

The objective of this publication is to describe the rationale behind the design of and report on the recruitment for the ongoing pediatric Grazax Asthma Prevention (GAP) trial.

METHODS

The trial was designed for assessment of the preventive effect of an SQ-standardized grass allergy immunotherapy tablet (AIT) on asthma development, both during treatment and after the end of treatment. (The standardized quality [SQ] procedure is a standardization procedure comprising 3 components: total potency, major allergen content, and assessment of extract complexity.) The trial design was discussed with several European Competent Authorities.

RESULTS

The GAP trial is a multinational, parallel-group, double-blind, placebo-controlled randomized trial. Main eligibility criteria were age of 5 to 12 years, grass pollen-induced allergic rhinoconjunctivitis, no asthma, and no overlapping symptomatic allergies. The children have been randomized 1:1 to receive the grass AIT or placebo once daily for 3 years, followed by a blinded observational period of 2 years. Asthma is assessed by the investigators according to specific diagnostic criteria, used at screening visits before randomization to exclude children with existing asthma, and evaluated at least half-yearly during the trial. Seven months of screening resulted in 812 randomized children at 101 centers in 11 countries.

CONCLUSIONS

To our knowledge, the GAP trial represents the first double-blind, placebo-controlled randomized trial to assess the preventive effect of allergen-specific immunotherapy on asthma development. A total of 812 children were successfully recruited into the trial. EudraCT number: 2009-011235-12.

European Academy of Allergy and Clinical Immunology task force report on 'dose-response relationship in allergen-specific immunotherapy'

BACKGROUND

For a century, allergen-specific immunotherapy (SIT) has proven to be an effective treatment for allergic rhinitis, asthma, and insect sting allergy. However, as allergen doses are frequently adapted to the individual patient, there are few data on dose-response relationship in SIT. Allergen products for SIT are being increasingly required to conform to regulatory requirements for human medicines, which include the need to demonstrate dose-dependent effects.

METHODS

This report, produced by a Task Force of the EAACI Immunotherapy Interest Group, evaluates the currently available data on dose-response relationships in SIT and aims to provide recommendations for the design of future studies.

RESULTS

Fifteen dose-ranging studies fulfilled the inclusion criteria and twelve reported a dose-response relationship for clinical efficacy. Several studies also reported a dose-response relationship for immunological and safety endpoints. Due to the use of different reference materials and methodologies for the determination of allergen content, variations in study design, and choice of endpoints, no comparisons could be made between studies and, as a consequence, no general dosing recommendations can be made.

CONCLUSION

Despite recently introduced guidelines on the standardization of allergen preparations and study design, the Task Force identified a need for universally accepted standards for the measurement of allergen content in SIT preparations, dosing protocols, and selection of clinical endpoints to enable dose-response effects to be compared across studies.

Sublingual immunotherapy in children with allergic rhinitis: quality of systematic reviews

Systematic reviews have gained popularity as a way to combine the increasing amount of research information. This study assessed the quality of systematic reviews and meta-analyses of sublingual immunotherapy (SLIT) for allergic rhinitis in children, published since 2000. Eligible reviews were identified by searching Medline/Pubmed, Embase, and the Cochrane Library, from 2000 through 2008. Methodological quality was assessed using the assessment of multiple systematic reviews instrument. Ten systematic reviews were included, one of which was published in the Cochrane Library. Eight reviews gave some details about the search strategy. None of the reviews included measures to avoid selection bias. In 60% of the reviews, the methodological quality of the included studies was (partly) assessed. Four reviews pooled the results of individual studies, neglecting clinical heterogeneity. Three of the 10 reviews provided information about sources of funding or grants from industry. Of the 10 reviews, the six reviews with the highest overall score scored 5-8 points, indicating moderate quality. Systematic reviews are useful to evaluate the efficacy of SLIT in children. Although more reviews have become available, the methodological quality could be improved. SLIT for children could be promising, but methodological flaws in the reviews and individual studies are too serious to draw definite conclusions.

Safety of accelerated schedules of subcutaneous allergen immunotherapy with house dust mite extract in patients with atopic dermatitis

The safety of accelerated schedules of allergen immunotherapy (ASAI) in patients with bronchial asthma (BA) has been reported but there are little data on the safety of ASAI for patients with atopic dermatitis (AD). In this study, we investigated the safety of ASAI in patients with AD. Sixty patients with AD and 18 patients with BA sensitized to house dust mites (HDM) were studied. A maximum maintenance dose of HDM extract, adsorbed to aluminum hydroxide, was administered to patients by subcutaneous injection with either a 3-day protocol (rush immunotherapy) or 1-day protocol (ultra-rush immunotherapy). Systemic reactions were observed 4 of 15 patients (26.7%) with AD during rush immunotherapy, 13 of 45 patients (28.9%) with AD during ultra-rush immunotherapy, and 4 of 18 patients (22.2%) with BA during rush immunotherapy (P > 0.05). No severe or near fatal systemic reactions occurred in 78 subjects of this study. Systemic reactions developed within 4 hr after administration of the maximum allergen dose in 20 of 21 patients (95.2%) with AD and BA who showed systemic reactions during rush or ultra-rush immunotherapy. In conclusion, ASAI was safe and well tolerated in patients with AD. ASAI can be a useful therapeutic option for AD.

Allergen-specific immunotherapy: which outcome measures are useful in monitoring clinical trials?

Various clinical outcome measures are commonly applied in clinical trials on specific immunotherapy for allergic rhinoconjunctivitis with or without asthma to provide evidence of its clinical efficacy. These "primary endpoints" measure clinical symptoms as well as the use for concomitant medication. "Secondary outcome endpoints" are represented by health-related quality of life (HRQoL), "well-days," provocation-tests, in vitro tests and others. This article reviews different methods assessing the clinical outcome of trials on both subcutaneous and sublingual immunotherapy, and highlights potential advantages and drawbacks of each method.

Sublingual immunotherapy for allergic respiratory diseases: efficacy and safety

Subcutaneous immunotherapy (SCIT) is effective and safe when properly prescribed and administered. However, a certain risk of severe side effects exists, even when the reaction is managed correctly. These potential adverse effects stimulated the search for new administration routes (nasal, bronchial, oral, sublingual), which were expected to be safer. Not all of these alternative routes provided an improved benefit-safety profile compared with SCIT. The sublingual route (SLIT) seemed to be a good candidate for the clinical practice because of its satisfactory safety profile and is now considered an acceptable alternative to SCIT in adults and children.

Close collaboration between academia, industry and drug regulators is required in the development of allergen products for specific immunotherapy in children

Modification of the response to allergens at an early stage and thereby of the natural history of a respiratory allergic disease by preventing disease progression would constitute the key benefit of specific immunotherapy (SIT) in children. However, although allergen products for SIT have been on the market on a named-patient basis for many years, long-term efficacy, the optimal duration of the treatment and the optimal dosage have not been sufficiently elaborated until now. The enactment of the Therapy Allergen Ordinance in Germany mandates that allergen products for SIT of the most prevalent allergies must submit an application for marketing authorization to the German authorities. In line with the European Paediatric Regulation, decisions by the European Medicines Agency on agreed paediatric investigation plans must be included in these applications. These regulatory requirements provide a unique opportunity to fill the gap in knowledge concerning the benefits of SIT for children and to obtain the data needed to support evidence-based authorization of allergen products for immunotherapy. This goal can only be achieved through close cooperation between academia, drug regulators and industry as well as parent/patient organizations.

Effect of allergen immunotherapy practice parameters on cat extract prescribing patterns, 1993-2009

BACKGROUND

Cat extract allergen immunotherapy (AIT) is an effective treatment for cat allergy. The prescribed dose for cat AIT varies among prescribers, despite published data supporting an effective dose range. The original practice parameter published in December 1996 did not recommend a dose of cat allergen, but updates in January 2003 and September 2007 recommend cat extract dose ranges of 2,000 to 3,000 BAU and 1,000 to 4,000 BAU, respectively.

OBJECTIVE

To describe the prescribing patterns for cat AIT among practicing allergists in a large health care system and the effect of practice parameters on these patterns.

METHODS

A total of 27,788 prescriptions were analyzed to determine the date and amount of maintenance dose cat allergen prescribed. The data were subdivided into periods before and after the 3 published AIT practice parameters.

RESULTS

From January 2003 to September 2007, 1,810 prescriptions (18.0%) were written in the recommended range. From September 2007 to May 2009, 3,143 prescriptions (82.6%) were written in the recommended range. Cat AIT maintenance doses were 1,000 to 4,000 BAU 22.1% of the time before January 2003, 61.8% from January 2003 to September 2007, and 82.6% from September 2007 to May 2009.

CONCLUSIONS

In this large systemic evaluation of cat AIT prescribing patterns, maintenance dose recommendations in the AIT practice parameters were associated with changes in the prescribing patterns for cat AIT. Most prescriptions for cat AIT were inconsistent with recommended doses in the AIT practice parameters between 2003 and 2007. Dosing within recommended ranges improved after 2007, in part due to a widening of the recommended dose range.

Assessment of clinical efficacy of CYT003-QbG10 in patients with allergic rhinoconjunctivitis: a phase IIb study

BACKGROUND

Allergic symptoms are generally caused by exposure to substances to which people have become sensitized. Associated with this is an 'unbalanced' Th1/Th2 immune response with T cell responses skewed towards the production of Th2 cytokines, IL-4, 5, and 13 and high levels of IgE antibodies. Current immune modulating therapies require the use of allergens, carrying the risk to induce potentially severe allergic reactions.

OBJECTIVE

Goal of the present study was to assess the safety and efficacy of an allergen-free immune modulator in patients suffering from perennial allergy.

METHODS

In order to be protected from immediate degradation upon injection, a toll-like receptor 9 (TLR9) agonist was packaged into virus-like particles. These nanoparticles loaded with TLR9 ligands (CYT003-QbG10) were injected six times, at weekly intervals, into patients with house dust mite allergy in an attempt to ameliorate allergic symptoms by modifying the immune response towards allergens. Two different doses were compared against placebo in this double-blind, randomized phase IIb study (n=299). Public trial registry: http://clinicaltrials.gov (NCT00800332).

RESULTS

The treatment was safe and generally well tolerated. Rhinoconjunctivitis symptoms were significantly lower in patients treated with high dose of CYT003-QbG10 as compared with placebo (scores 0.31 vs. 0.52, P=0.04) based on a standardized average combined symptom and medication score. Furthermore, patients in the high dose group reported a significantly better quality of life score post-treatment than patients on placebo (scores 0.71 vs. 1.21, P=0.02). The conjunctival provocation test revealed a median 10-fold increase in allergen tolerance in the high dose group while in the placebo group it remained unchanged.

CONCLUSION AND CLINICAL RELEVANCE

Treatment with high-dose CYT003-QbG10 improved disease symptoms and reduced medication use in allergic individuals thus providing first evidence for a new potential immunotherapeutic.

Strategies of mucosal immunotherapy for allergic diseases

Incidences of allergic disease have recently increased worldwide. Allergen-specific immunotherapy (SIT) has long been a controversial treatment for allergic diseases. Although beneficial effects on clinically relevant outcomes have been demonstrated in clinical trials by subcutaneous immunotherapy (SCIT), there remains a risk of severe and sometimes fatal anaphylaxis. Mucosal immunotherapy is one advantageous choice because of its non-injection routes of administration and lower side-effect profile. This study reviews recent progress in mucosal immunotherapy for allergic diseases. Administration routes, antigen quality and quantity, and adjuvants used are major considerations in this field. Also, direct uses of unique probiotics, or specific cytokines, have been discussed. Furthermore, some researchers have reported new therapeutic ideas that combine two or more strategies. The most important strategy for development of mucosal therapies for allergic diseases is the improvement of antigen formulation, which includes continuous searching for efficient adjuvants, collecting more information about dominant T-cell epitopes of allergens, and having the proper combination of each. In clinics, when compared to other mucosal routes, sublingual immunotherapy (SLIT) is a preferred choice for therapeutic administration, although local and systemic side effects have been reported. Additionally, not every allergen has the same beneficial effect. Further studies are needed to determine the benefits of mucosal immunotherapy for different allergic diseases after comparison of the different administration routes in children and adults. Data collected from large, well-designed, double-blind, placebo-controlled, and randomized trials, with post-treatment follow-up, can provide robust substantiation of current evidence.

Specific immunotherapy: beyond the clinical scores

OBJECTIVE

The efficacy of specific immunotherapy always has been evaluated by clinical scores (symptoms or medication intake). Nonetheless, specific immunotherapy possesses some special or "additional" effects, including the carryover effect and the preventive actions, which are unique. Those effects are the consequence of the complex mechanism of action, which induces profound and persistent modifications in the immune response to allergens. The literature is reviewed to evaluate the available experimental data on this.

DATA SOURCES

The main databases (EmBase, Medline, Scopus) were searched.

STUDY SELECTION

Clinical trials of immunotherapy, either randomized or not, including placebo-controlled trials, were selected.

RESULTS

Currently, the carryover effect (persistence of the benefit after stopping the treatment) is well ascertained for injection immunotherapy, whereas fewer data are available for the sublingual route. On the contrary, the demonstration of the prevention of asthma onset relies on 2 randomized studies for sublingual immunotherapy, and 1 single study for subcutaneous immunotherapy.

CONCLUSION

Although additional confirmatory data are needed, possibly obtained with a rigorous methodology, the long-lasting and preventive effects of specific immunotherapy always should be taken into account when the efficacy is evaluated. The additional effects also may have relevant socioeconomic implications.

How to design and evaluate randomized controlled trials in immunotherapy for allergic rhinitis: an ARIA-GA(2) LEN statement

Specific immunotherapy (SIT) is one of the treatments for allergic rhinitis. However, for allergists, nonspecialists, regulators, payers, and patients, there remain gaps in understanding the evaluation of randomized controlled trials (RCTs). Although treating the same diseases, RCTs in SIT and pharmacotherapy should be considered separately for several reasons, as developed in this study. These include the severity and persistence of allergic rhinitis in the patients enrolled in the study, the problem of the placebo, allergen exposure (in particular pollen and mite), the analysis and reporting of the study, the level of symptoms of placebo-treated patients, the clinical relevance of the efficacy of SIT, the need for a validated combined symptom-medication score, the differences between children and adults and pharmacoeconomic analyses. This statement reviews issues raised by the interpretation of RCTs in sublingual immunotherapy. It is not possible to directly extrapolate the rules or parameters used in medication RCTs to SIT. It also provides some suggestions for the research that will be needed. Interestingly, some of the research questions can be approached with the available data obtained from large RCTs.

Regulatory environment for allergen-specific immunotherapy

Products for specific immunotherapy (SIT) are medicinal products according to the European Regulations. To obtain a marketing authorization (MA) within the European Community, the quality, safety and efficacy have to be proven. During the development phase of a medicinal product, applicants have the opportunity to apply for scientific advice by national competent authorities or the European Medicines Agency (EMA) to compile a suitable development plan for the examination of quality and performance of nonclinical and clinical trials. Moreover, a paediatric investigation plan has to be submitted to the Paediatric Committee of the EMA and has to be approved before submission of an application for MA. Several regulatory procedures exist for obtaining a MA in the European Community. The national procedure leads only to marketability in one country whereas the Mutual Recognition, the Decentralized and Centralized Procedures (CP) are intended for MA in several or all member states of the European Union. The CP is mandatory for certain medicinal products, for example for drug substances derived by biotechnological processes such as recombinant allergens. Named Patient Products for SIT are a specialty because they are manufactured on the basis of an individual prescription and marketed without a MA.

The current state of recombinant allergens for immunotherapy

PURPOSE OF REVIEW

Subcutaneous immunotherapy is a well documented treatment of allergic rhinitis and asthma. The majority of the disadvantages of the treatment are related to the poor quality of the natural allergen extracts which can contain varying amounts of individual allergens including allergens to which the patient may not be sensitized. Recombinant allergens offer a possibility to use well defined molecules with consistent pharmaceutical quality defined in mass units. The proof of concept of the clinical efficacy of recombinant allergens is based on two studies published as full articles.

RECENT FINDINGS

One study applied a mixture of five Phleum pratense major allergens in a maximum dose of 40mcg protein. The clinical efficacy showed a significant efficacy with 40% reduction in disease severity. The second study compared a commercial birch extract with both recombinant Bet v 1 and purified Bet v 1 in dosages of 15mcg allergen. The clinical effect was 60% additional efficacy. Systemic side effects occurred more frequently with grass allergens. A third study used hypoallergenic fragments and a trimer of Bet v 1. The study did not show efficacy and a rather high frequency of systemic side effects.

SUMMARY

The advantages of using recombinant allergens for immunotherapy are obvious but more studies on a large scale are needed before the overall value in terms of efficacy and safety can be assessed. Clinical trials are also necessary for new combined vaccines based on recombinant allergens that in experimental studies have shown greatly enhanced immunogenicity and low allergen-specific reactivity.

Prospective validation of 'Allergy-Control-SCORE(TM)': a novel symptom-medication score for clinical trials

BACKGROUND

Combined symptom and medication scores (SMS) are recommended as primary endpoints in clinical trials. Several SMS have been created, but none has been formally validated.

OBJECTIVE

To evaluate the validity of the 'Allergy-Control-SCORE© (ACS)', a novel instrument to assess patient's allergy severity by recording symptoms and rescue medication.

METHODS

One hundred and twenty-one consenting subjects (age 18-65 year), including 81 patients with allergic rhino-conjunctivitis and/or asthma and 40 healthy controls, participated in the study. They recorded daily nasal, eye, and lung symptoms using a 4-point scale (none, mild, moderate, and severe) and use of anti-symptomatic medication. Pollen counts were monitored during the study period. Symptom and medication scores values were compared to global allergy severity, quality of life, and allergy-related medical consultations. Feasibility was tested through a questionnaire on comprehensibility, easiness of use, and completeness. Retest reliability was assessed by testing consistency, in relation to pollen exposure, and for values recorded during each of 2 consecutive weeks.

RESULTS

Convergent reliability analysis indicated a highly significant correlation between ACS© and global allergy severity (P < 0.0001), quality of life (P < 0.0001), and allergy-related medical consultations (P < 0.0001). Scores were highly related to pollen counts. Allergy-Control-SCORE© showed a good retest reliability (r = 0.81; P < 0.0001) and discriminated extremely well between patients with allergy and healthy controls (6.1 ± 4.8 vs 0.2 ± 0.5; t = 10.82; P < 0.0001) with a sensitivity of 97% and a specificity of 87%. Study participants evaluated the feasibility of the SMS as excellent.

CONCLUSIONS

Allergy-Control-SCORE© is a valid and reliable instrument to assess allergy severity in clinical trials and observational studies of respiratory allergic diseases.

Allergy immunotherapy tablet: Grazax® for the treatment of grass pollen allergy

Immunotherapy is the only treatment for allergy that alters the natural course of this disease. Sublingual immunotherapy has been developed to make immunotherapy more suitable for allergic patients. In the largest clinical program ever conducted with grass allergen-specific immunotherapy, over 2000 adults and more than 500 children have been exposed to Grazax(®) (ALK-Abello A/S, Hoersholm, Denmark). Grazax is an oral lyophilisate tablet (allergy immunotherapy tablet [AIT]) for sublingual administration, containing 75,000 standardized quality tablet units of allergen extract of grass pollen (Phleum pratense). Grazax is indicated for treatment of grass pollen-induced rhinitis and conjunctivitis in adult and pediatric patients. Results from the GT-08 trial (first, second and third treatment years) showed a reduction of 31, 36 and 29%, respectively, in symptom scores and a reduction of 38, 45 and 40% of medication scores, respectively, compared with placebo. Subjects treated with Grazax also had an increased number of well days and a relevant improvement in quality of life. More subjects experienced excellent and complete rhinoconjunctivitis control in comparison with patients treated with symptomatic medications only. Grazax treatment is also associated with a sustained and relevant increase of specific IgG4. This increase is also observed after stopping AIT treatment. The most common adverse events related to Grazax treatment are local reactions, such as oral itch, edema of the mouth, ear pruritus, throat irritation and sneezing. Clinical efficacy of Grazax is observed also after 1 and 2 years of follow-up after stopping the AIT treatment. Grazax is efficacious and safe for treatment of grass-pollen rhinoconjunctivitis in both adults and children. Grazax is the first AIT showing a disease-modifying effect on grass pollen-induced allergic rhinoconjuctivitis.

Clinical and immunologic effects of sublingual immunotherapy on patients with allergic rhinitis to house-dust mites: 1-year follow-up results

BACKGROUND

There have been no data on sublingual immunotherapy (SLIT) in Asian patients with allergic rhinitis (AR) sensitized to house-dust mites (HDMs). This study aimed to investigate the efficacy and immunologic change after 12 months of SLIT in Korean patients.

METHODS

Fifty-eight patients, who had AR caused by Dermatophagoides pteronyssinus and Dermatophagoides farinae and who completed 12 months of SLIT were included. Symptom scores were evaluated before and after 12 months of SLIT, and medication scores were assessed throughout the study. Peripheral blood eosinophil counts, eosinophil cationic protein (ECP), total IgE, and specific IgE were also evaluated.

RESULTS

All of the symptoms of AR were significantly improved with reduced medication scores. In addition, there were significant decrements in peripheral blood eosinophil counts and ECP (p = 0.025 and p = 0.048, respectively). Specific IgE for D. farinae slightly increased (p = 0.019), whereas specific IgE for D. pteronyssinus and total IgE did not change significantly. Thirty-six (62%) of 58 patients were in the effective response group. Although not statistically significant, findings in the study showed that the effective response group had a tendency to have higher ECP levels before SLIT than the ineffective response group (p = 0.056).

CONCLUSION

SLIT improved the symptoms and medication scores in Korean patients with AR from HDM. Laboratory parameters including eosinophil counts, ECP, and specific IgE for D. farinae seemed to be modified after 1-year SLIT. A high ECP level may be a useful parameter to predict the effectiveness of SLIT and select the patient for the treatment.

Three years of specific immunotherapy may be sufficient in house dust mite respiratory allergy

BACKGROUND

Specific immunotherapy (SIT) duration for respiratory allergy is currently based on individual decisions.

OBJECTIVE

To evaluate the differences in clinical efficacy of SIT as a result of the duration between the current recommended limits (3-5 years).

METHODS

A 5-year prospective, controlled clinical trial of SIT blind until the first year and randomization to a 3-year (IT3) or 5-year (IT5) course was conducted. Of the 239 patients with respiratory allergy caused by D pteronyssinus initially included, 142 completed 3 years of SIT with good compliance. Twenty-seven controls were included at the third year. Efficacy of SIT after 3 (T3) and 5 (T5) years was assessed by using clinical scores, visual analog scales (VASs), rhinitis (RQLQ) and asthma (AQLQ) quality of life questionnaires, skin tests, and serum immunoglobulins.

RESULTS

At T3, significant reductions were observed in rhinitis (44% in IT3 and 50% in IT5; P < .001), asthma (80.9 % in IT3 and 70.9% in IT5; P < .001) scores, VAS (P < .001 in both), RQLQ (P < .001 in both) and AQLQ (P < .001 in both). At T5, the clinical benefit was maintained in both groups, and IT5 patients presented additional decreases (19%; P = .019) in rhinitis scores. At Tf, specific IgG(4) measurements were lower in IT3 (P = .03) without detecting differences in IT5. An increase in asthma score of 133% was the only difference observed in controls.

CONCLUSION

Clinical improvement is obtained with 3 years of D pteronyssinus SIT. Two additional years of SIT add clinical benefit in rhinitis only.