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

The allergen challenge chamber: a valuable tool for optimizing the clinical development of pollen immunotherapy

The clinical development of allergen immunotherapy for allergic rhinoconjunctivitis because of pollen is complicated by seasonal, geographical and subject-related variability in allergen exposure. Using an allergen challenge chamber (ACC), a room that enables reproducible challenges with controlled levels of inhalant allergens for several hours, these factors can be controlled. The ACC has often been used to evaluate symptomatic medications but is underexploited in the field of allergen immunotherapy. When used in conjunction with a programme of natural-exposure trials, the ACC enables researchers to (i) facilitate the allergen immunotherapy dose-finding process, (ii) accelerate the transition from Phase I/II to Phase III trials, (iii) characterize the onset and maintenance of action, (iv) avoid the confounding effects of rescue medication, (v) better characterize the baseline or pretreatment characteristics of trial subjects, (vi) perform better-standardized physical and laboratory measurements during an acute challenge, (vii) simplify trial logistics and use smaller numbers of subjects than would be required in equivalent natural-exposure studies and (viii) support (but not replace) Phase III natural-exposure trials for the investigation into long-term and disease-modifying effects. ACC studies can further increase levels of evidence for allergen immunotherapy--the only current therapy potentially capable of modifying the underlying allergic disease.

Swedish translation and validation of the Pediatric Allergic Disease Quality of Life Questionnaire (PADQLQ)

AIM

The aim of the study was to translate and validate the PADQLQ (Pediatric Allergic Disease Quality of Life Questionnaire), a disease-specific quality of life questionnaire for the assessment of quality of life in children with pollen allergy.

METHODS

The PADQLQ was translated into Swedish according to guidelines. Children aged 7-18 with grass pollen allergy were included. Quality of life was assessed in parallel with ordinary symptom scales (VAS) before, during and after the pollen season.

RESULTS

A total of 98 children were included and 89 (91%) completed the study. The results for PADQLQ showed good cross-sectional and longitudinal validity. The retrospective estimation after the season showed good consensus with the assessment during pollen season.

CONCLUSION

Quality of life in children assessed with the PADQLQ (Pediatric Allergic Disease Quality of Life Questionnaire) is a reliable strategy for evaluating the burden of disease in children with pollen allergy and for the evaluation of treatment.

Clinical practice: Allergen-specific immunotherapy in children: facts and FAQs

Allergen-specific immunotherapy (SIT) in its various application forms represents the main treatment approach of IgE-mediated allergic diseases in adults and children. Despite this clear recommendation, many particularities of products, patient characteristics, and product availability in different countries hamper the use of allergen-specific immunotherapy in particular in children. The frequently asked questions by parents, patients, and physicians are the backbone of this review. Thus, the potentials and limitations of allergen-specific immunotherapy in children and adolescents will be highlighted. IgE-mediated allergic diseases are affecting about 20% of the population. They manifest commonly early in life, and hence, the use of SIT should be considered also early in the course of the disease.

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.

The clinical efficacy of a sublingual monomeric allergoid at different maintenance doses: a randomized controlled trial

Sublingual immunotherapy is widely recognized as a viable treatment for allergic rhinitis and asthma, but the optimal dosage is still under debate, especially with modified allergens. We assessed the clinical effects of a monomeric allergoid across 3 different maintenance doses in mite-monosensitized patients with rhinitis and intermittent asthma. Eighty-nine patients allergic to HDM were randomized to 3 maintenance doses of monomeric allergoid (Lais, Lofarma) or medications only. All the patients recorded their symptoms and rescue drug consumption in a diary card from November to February. Additionally, nasal eosinophil count, spirometry and methacholine bronchial challenge were performed at the beginning of the study and after 3 years. The symptom scores showed a clear improvement in all the three active arms versus baseline and versus the controls, irrespective of the dose. Likewise, a similar improvement versus baseline was seen for nasal inflammation and bronchial hyperreactivity. The SLIT with monomeric allergoids produces clinically significant results across a wide range of doses. The absence of significant side effects, even at high doses, is probably due to their low level of allergeni city.

Registration trials for specific immunotherapy in Europe: advanced guidance from the new European Medical Agency guideline

Marketing authorization of medicinal products is granted based on results of registration trials. The European Medical Agency (EMA) has issued general and disease state-specific guidelines for the conduct of such trials. In the area of allergic diseases, there are basically two general therapeutic approaches: Drugs that mitigate the symptoms and an approach that is targeted to the root cause of the disease, the allergen-specific immunotherapy (SIT). While the 'Guideline on the Clinical Development of Medicinal Products for the Treatment of Allergic Rhino-Conjunctivitis' (CHMP/EWP/2455/02) and the 'Note for Guidance on the Clinical Investigation of Medicinal Products in the Treatment of Asthma' (CPMP/EWP/2922/01) focuses exclusively on the development of medicinal products to treat allergic symptoms, there was no guideline for SIT in the past. In consequence, the conduct of clinical trials for SIT was widely lacking a standardized approach. This created difficulties when comparing drugs and outcomes and also uncertainty to predict marketing authorization. In 2009, the EMA has issued a new guideline on the clinical development of products for SIT. Despite some white spots in some areas, the new guideline constitutes a breakthrough with regard to guidance, harmonization and transparency in the conduct of clinical trials in SIT.

Subcutaneous specific immunotherapy for seasonal allergic rhinitis: a review of treatment practices in the US and Europe

BACKGROUND

Subcutaneous specific immunotherapy (SCIT) is claimed to be successful both in the US and Europe, yet treatment methodology differs.

METHODS

The authors review current literature surrounding guidelines and clinical trials in Europe and the US and contrast the treatment approach to SCIT for allergic rhinitis. Search methodology employs MEDLINE and PubMed, selecting articles on SCIT and allergic rhinitis, limited between 1990-2009. They focus on the safety and efficacy of vaccines, and the differences in formulations. Also mentioned are: standardization, new approaches in SCIT and sublingual immunotherapy (SLIT).

RESULTS

SCIT treatment differs in many respects regarding availability of SCIT products, regulatory controls, guidelines (e.g. multiple allergen vaccines in US, single allergen vaccines in Europe) and in location of formulation (US, clinician's office; Europe, manufacturers).

CONCLUSIONS

SCIT is an effective and safe therapy, but major evidence for efficacy is provided from European studies of single allergen extract vaccines; these vaccines may gain more acceptance because of increasing regulatory approval and lower numbers of injections. The potential impact upon public health (e.g. arrest of the 'allergic march') should not be overlooked.

Emerging sublingual immunotherapy drugs

IMPORTANCE OF THE FIELD

There is epidemiological evidence that respiratory allergy has reached epidemic proportions; owing to the related socio-economic impact, this topic deserves particular attention. An integrated approach involving pharmacotherapy and the immunomodulatory effect of immunotherapy is expected to optimize the management of respiratory allergy, reducing its clinical and economic burdens. Sublingual immunotherapy (SLIT) has gained increasing interest for its efficacy comparable to traditional subcutaneous immunotherapy and its good safety profile.

AREAS COVERED IN THIS REVIEW

A review of the up-to-date state of the art concerning the key aspects of SLIT is provided; the critical issues are discussed in the light of the comprehensive revision of the recent World Allergy Organization position paper and the subsequent literature, paying particular attention to efficacy, safety, additional effects, adherence and clinical developments.

WHAT THE READER WILL GAIN

The overview of current certainties and concerns, related to the use of SLIT, allows the reader's insight into the future directions of research and clinical applications of SLIT, aimed at covering current unmet needs.

TAKE HOME MESSAGE

A large amount of experimental evidence sustains the use of SLIT, though some aspects still need to be clarified to provide clear, evidence-based recommendations. Unmet needs represent the basis for future research, while clinical hypotheses would open the search for new indications and modalities.

Long-lasting effects of sublingual immunotherapy according to its duration: a 15-year prospective study

BACKGROUND

Data on the long-term effects of sublingual immunotherapy (SLIT) are sparse, and the optimal duration of treatment is a matter of debate.

OBJECTIVE

We sought to prospectively evaluate the long-term effect of SLIT given for 3, 4, or 5 years and to compare the effect of those different durations.

METHODS

In this prospective open controlled study we followed up patients with respiratory allergy who were monosensitized to mites for 15 years. The subjects were divided in 4 groups receiving drug therapy alone or SLIT for 3, 4, or 5 years. Clinical scores, skin sensitizations, methacholine reactivity, and nasal eosinophil counts were evaluated every year during the winter months. The clinical effect was considered to persist until clinical scores remained at less than 50% of the baseline value, and then patients underwent another course of SLIT.

RESULTS

Seventy-eight patients were enrolled, and 59 completed the study. In the 12 control subjects no relevant change in clinical scores was seen throughout the study. In the patients receiving SLIT for 3 years, the clinical benefit persisted for 7 years. In those receiving immunotherapy for 4 or 5 years, the clinical benefit persisted for 8 years. New sensitizations occurred in all the control subjects over 15 years and in less than a quarter of the patients receiving SLIT (21%, 12%, and 11%, respectively). The second course of vaccination induced a benefit more rapidly than the first course. The behavior of bronchial hyperreactivity and nasal eosinophils paralleled the clinical score.

CONCLUSION

Under the present conditions, it can be suggested that a 4-year duration of SLIT is the optimal choice because it induces a long-lasting clinical improvement similar to that seen with a 5-year course and greater than that of a 3-year vaccination.

Sublingual immunotherapy for Alternaria-induced allergic rhinitis: a randomized placebo-controlled trial

BACKGROUND

Respiratory allergy due to Alternaria is a relevant clinical problem, and specific immunotherapy may represent a viable treatment option. Sublingual immunotherapy (SLIT) is safe and effective, but data for Alternaria are lacking.

OBJECTIVE

To assess the efficacy of standardized SLIT in patients sensitized to Alternaria in a randomized, prospective, double-blind, placebo-controlled trial.

METHODS

Patients with rhinitis with or without intermittent asthma and ascertained allergy to Alternaria were enrolled. After a baseline season, SLIT or matched placebo was given for 10 months. Symptoms and rescue medication intake were recorded on diary cards between June and October. Skin prick testing was performed and specific IgE, IgG4, and precipitin levels were measured at baseline and at the end of the study.

RESULTS

Twenty-seven patients (age range, 14-42 years) were randomized, and 26 completed the study. The baseline characteristics were homogeneous in the 2 groups. After treatment, patients receiving SLIT had a significant improvement in symptoms and a reduction in medication intake vs placebo and vs the run-in season, whereas no change was seen in the placebo group. Skin prick test reactivity significantly decreased only in the SLIT group. No change was seen in specific IgG4 levels in the 2 groups, whereas Alt a 1 specific IgE levels significantly increased in the active group. One patient in the active group reported oral itching and conjunctivitis at the beginning of treatment.

CONCLUSION

SLIT seems effective and safe and may represent a valuable therapeutic option in respiratory allergy due to Alternaria.

Endonasal phototherapy significantly alleviates symptoms of allergic rhinitis, but has a limited impact on the nasal mucosal immune cells

The literature documents the fact that UV irradiation of cutaneous Langerhans cells (LC) in vivo prevents the development of contact allergy and produces long-lasting immunosuppression. However, not much is known about the effect of UV irradiation on the LC of the nasal mucosa and their connection with clinical scores. Local antigen presentation may be necessary for both primary and recall T cell responses to birch pollen in patients with hay fever. Endonasal phototherapy combination of UVB (5%), UVA (25%) and visible light (70%) utilises the immunosuppressive effects of UV irradiation. The aim of this study was to correlate clinical symptom scores with possible changes in the LC of the nasal mucosa induced by UV radiation. The clinical effectiveness of this form of treatment is discussed. Nasal biopsies were obtained from ten birch pollen-sensitive patients with seasonal rhinitis before and after endonasal phototherapy. All patients showed a significant clinical benefit post-treatment as assessed by standardised instruments, including total nasal symptom score, nasal congestion score, nasal itching score, sneezing score, nasal secretion score and impairment-to-health score. However, we found no significant morphological changes, to, or quantitative differences in, the CD1a+, CD4, CD8 or CD31 cells before and 14 days after treatment. Despite the positive clinical effect, the study revealed no effect of UV irradiation on the LC and other analysed cells of the nasal mucosa immune system. Possible reasons for this are discussed.

Sublingual Immunotherapy: Clinical Indications in the WAO-SLIT Position Paper

Sublingual immunotherapy (SLIT) is a matter of only 20 years. Nonetheless, in this short period of time more than 60 randomized double blind placebo-controlled trials have been published, in addition to postmarketing surveillance studies and meta-analyses. The wide diffusion of SLIT in clinical practice and the large availability of experimental data prompted the WAO to publish a position paper on SLIT, to identify the indications, contraindications, and practical aspects of the treatment. On the basis of the available literature, SLIT is certainly indicated in allergic rhinitis in both adults and children. In this latter population, SLIT may exert a preventative effect on the development of asthma. The age seems not to represent a special problem. SLIT can be used also when asthma is associated to rhinitis, whereas it is not the first choice for the treatment of isolated asthma. The IgE-mediated mechanism and the clear identification of the causal role of the allergen are mandatory prerequisites for prescribing SLIT. The safety profile is excellent, but it is recommended that the first dose be given under medical supervision. Atopic dermatitis, latex allergy, and hymenoptera hypersensitivity are promising fields of use of SLIT, but they are still considered only experimental uses.

Sustained effect of SQ-standardized grass allergy immunotherapy tablet on rhinoconjunctivitis quality of life

BACKGROUND

The prevalence of allergic rhinoconjunctivitis has increased significantly over the past decades with grass pollen being a common trigger. The impact of allergy on patient's quality of life is substantial.

AIM

To investigate the sustained effect on quality of life during the grass pollen season 1 year after 3 years of treatment with the SQ-standardized grass allergy immunotherapy tablet (AIT), Graza (Phleum pratense 75,000 SQ-T/2800 BAU; ALK, Denmark).

METHODS

The trial was a randomized, parallel-group, double-blind, placebo-controlled trial in adult subjects with a history of moderate-severe grass pollen induced rhinoconjunctivitis inadequately controlled by symptomatic medications. Subjects received 3 years of grass AIT (n = 157) or placebo (n = 126), followed by 1 year of follow-up. Quality of life assessments were based on the standardized rhinoconjunctivitis quality of life questionnaire (RQLQ(S)); completed weekly during the entire grass pollen season.

RESULTS

During follow-up, the overall RQLQ(S) score for the entire grass pollen season was significantly improved in the active group (relative difference to placebo: 23%, P = 0.004). The improvement was higher during the peak pollen season (28%, P = 0.001). The treatment effect of grass AIT during the follow-up year and the previous three treatment years was similar. Improvements were found in all seven RQLQ(S) domains. The RQLQ(S) as a function of the weekly average pollen counts showed a clear separation between the treatment groups (P < 0.001).

CONCLUSION

In subjects inadequately controlled by symptomatic medications, grass AIT provided sustained and clinically relevant improvements in rhinoconjunctivitis quality of life compared to placebo. The effect increased with increasing grass pollen exposure.

Evidence of adherence to allergen-specific immunotherapy

PURPOSE OF REVIEW

The main feature of allergen-specific immunotherapy is its capacity to modify the natural history of the disease, reducing the development of asthma and new sensitizations after 3-4 years of treatment. For this reason, adherence to the therapy is mandatory, as happens for all chronic medical treatment.

RECENT FINDINGS

Though subcutaneous immunotherapy is administered directly by physicians, the rate of adherence is surprisingly low, at less than 70%. The explanations for a poor subcutaneous immunotherapy adherence include inconvenience, lack of efficacy, costs and loss of working hours.Local nasal immunotherapy has a very low adherence rate (27%), due to the local nasal side effects.For sublingual immunotherapy, data are available from clinical trials and postmarketing surveys, which are favourable overall (rates of compliance >75%). Cost was the most common reason for discontinuation, followed by inconvenience, feeling of inefficacy and side effects.

SUMMARY

Studies addressing the adherence to allergen-specific immunotherapy in literature are lacking. In real life, costs and patient education are crucial issues in conditioning adherence to this treatment. Reduction of costs and more efforts in education of patients and also specialists may improve the adherence to immunotherapy.

Antigen-specific immunotherapy against allergic rhinitis: the state of the art

Allergic rhinitis is the most prevalent type I allergy in industrialized countries. Pollen scattering from trees or grasses often induces seasonal allergic rhinitis, which is known as pollinosis or hay fever. The causative pollen differs across different areas and times of the year. Impaired performance due to pollinosis and/or medication used for treating pollinosis is considered to be an important reason for the loss of concentration and productivity in the workplace. Antigen-specific immunotherapy is an only available curative treatment against allergic rhinitis. Subcutaneous injection of allergens with or without adjuvant has been commonly used as an immunotherapy; however, recently, sublingual administration has come to be considered a safer and convenient alternative administration route of allergens. In this review, we focus on the safety and protocol of subcutaneous and sublingual immunotherapy against seasonal allergic rhinitis. We also describe an approach to selecting allergens for the vaccine so as to avoid secondary sensitization and adverse events. The biomarkers and therapeutic mechanisms for immunotherapy are not fully understood. We discuss the therapeutic biomarkers that are correlated with the improvement of clinical symptoms brought about by immunotherapy as well as the involvement of Tr1 and regulatory T cells in the therapeutic mechanisms. Finally, we focus on the current immunotherapeutic approach to treating Japanese cedar pollinosis, the most prevalent pollinosis in Japan, including sublingual immunotherapy with standardized extract, a transgenic rice-based edible vaccine, and an immunoregulatory liposome encapsulating recombinant fusion protein.

Basophil sensitivity through CD63 or CD203c is a functional measure for specific immunotherapy

Background

Subcutaneous Immunotherapy (SCIT) modifies the allergic response and relieves allergic symptoms. SCIT is the only and a very effective treatment for insect venom allergy. We hypothesized that basophil sensitivity, measured through the basophil activation test, would decrease during SCIT up dosing. Expression of CD203c was compared to CD63 as marker for basophil activation, using a Bland Altman plot and ROC curves.

Methods

Patients (n = 18) starting subcutaneous SCIT for wasp allergy with an up dosing scheme of 7 to 11 weeks were enrolled. Heparinised blood samples were drawn at weeks 1-4, 7 and at the first maintenance visit. Basophils were stimulated at 7 log dilutions of V. vespula allergen for 15 min, and were stained with CD203c and CD63. Basophils were identified as CD203c⁺ leukocytes, and the proportion of CD63⁺ and CD203c⁺ cells were plotted against allergen concentration. A sigmoid curve was fitted to the points, and the allergen concentration at which half of the maximal activation was achieved, LC50, was calculated. In another series of experiments, LC50 calculated in whole blood (AP) was subtracted from LC50 calculated with basophils suspended in plasma from a nonatopic donor (HS) to determine the protective effect of soluble factors in blood of patients treated with SCIT.

Results

Heparin blood basophil activation was similar through CD63 and CD203c. Basophils were significantly more sensitized three weeks after initiation of SCIT compared to baseline (p < 0,01). The difference in LC50 increased by 1,04 LC50 units (p = 0,04) in patients that had just achieved maintenance dose compared with patients before initiating SCIT. When maintenance allergen concentrations had been reached, an increase in the protective plasma component was documented. Blood basophil concentration was marginally reduced by SCIT.

Conclusion

Basophil activation is a versatile and sensitive tool that measures changes in the humoral immune response to allergen during SCIT.

Elispot and Elisa Assessment of Interferon-Gamma after Sublingual Immunotherapy

Allergic rhinitis (AR) is characterized by a Th2 polarized immune response, and specific immunotherapy modifies this arrangement, restoring a physiologic Th1 profile. Sublingual immunotherapy (SLIT) is widely prescribed. The aim of the study is to evaluate two different methods for assessing IFN-γ, namely ELISPOT and ELISA, before and after a pre-seasonal SLIT course as marker for Th1 response. Thirty-eight AR patients with pollen allergy assumed pre-seasonal SLIT for 3 months. Patients' blood samples for assessing IFN-γ serum levels were collected before initiating SLIT (baseline – T0), after 3 months pre-seasonal SLIT course (T1), and three months after completion of SLIT (T2). IFN-γ-specific producing cells, after allergen stimulation, were assessed by cytokine ELISPOT at the same time points. IFN-γ-specific producing cells significantly increased after SLIT both at T1 and T2 (p=0.0002). On the contrary, ELISA assessment did not reveal an increase in IFN-γ serum levels at any time point. In conclusion, these results demonstrate that ELISA assessment of serum IFN-γ is not suitable for identifying an early response.

The CONSORT statement checklist in allergen-specific immunotherapy: a GA2LEN paper

The methodology of randomized clinical trials is essential for the critical assessment and registration of therapeutic interventions. The CONSORT (Consolidated Standards of Reporting Trials) statement was developed to alleviate the problems arising from the inadequate reporting of randomized controlled trials. The present article reflects on the items that we believe should be included in the CONSORT checklist in the context of conducting and reporting trials in allergen-specific immunotherapy. Only randomized, blinded (in particular blinding of patients, health care providers, and outcome assessors), placebo-controlled Phase III studies in this article. Our analysis focuses on the definition of patients' inclusion and exclusion criteria, allergen standardization, primary, secondary and exploratory outcomes, reporting of adverse events and analysis.

[Allergen-specific Immunotherapy for children and adolescents - a review on available products in Austria]

A pediatric consensus report on allergen-specific immunotherapy for children and adolescents is presented for Austria. Products on the market in Austria are presented and categorised according to studies performed on the target population of children and adolescents, their effectiveness and indication. In general, more clinical studies on children and adolescents are mandatory for most of the available allergen-specific immunotherapeutics. In addition, the use of allergen-specific immunotherapy in general should be promoted as the exclusive treatment with long-lasting effects in type I allergies in particular in children.

Efficacy of sublingual specific immunotherapy in intermittent and persistent allergic rhinitis in children: an observational case-control study on 171 patients. The EFESO-children multicenter trial

Sublingual-specific immunotherapy (SLIT) is considered as a valid treatment of respiratory allergies. However, there are few data on large sample size regarding its clinical role in 'real life' in term of reduction of symptoms, rescue medications and prevention of asthma in patients suffering from allergic rhinitis (AR) especially in children. We performed a multicenter, case-control study to evaluate the effect of SLIT in children (age 6-18 yr) with intermittent or persistent AR. 171 children (27% girls and 73% boys) with AR due to seasonal or perennial allergens were enrolled in a multicenter case-control study. Cases (n = 90) were defined as patients with intermittent (64%) or persistent (36%) AR who were treated for at least two consecutive years with specific SLIT with the related allergen extracts (SLITone ALK-Abellò). Controls (n = 81) were defined as sex-age- and type of allergen matched AR children who were never treated with specific immunotherapy and had no asthmatic symptoms at the beginning of observation period. Main outcomes of the study were the rhinoconjunctivitis symptom score (SS) (sneezing, rhinorrea, nasal itch, congestion, ocular itch and watery eyes) with a ranging scale from 0 (=no symptoms) to 3 (=severe symptoms) and the medication score (MS) evaluating symptomatic drug intake (antihystamine and inhaled corticosteroids). SS and MS were evaluated at the end of the observational period in relation with the period, considering the last 12 months, in which patients suffered the highest symptoms levels (i.e., peak of relevant pollen season (seasonal AR) or during the period of maximum allergen exposure in case of perennial AR). Secondary outcome of the study was the development of asthma symptoms during the observation period. SS (mean +/- SD) was 4.5 +/- 2.5 in cases and 9.0 +/- 3.0 in controls (-50%) (p = 0.0001). MS (mean +/- SD) was 2.5 +/- 1.9 and 3.6 +/- 2.1 in the case and control groups, respectively (-31%) (p = 0.0001). At the end of the observation period asthma symptoms were present in 14 subjects in the case group (15%) and in 20 children (24%) in the control group (p = 0.13). New skin sensitizations appeared in 6% of cases (n = 2) and in 36% (n = 12) of the controls (p = 0.001). The EFESO trial shows that a 2-yr once daily SLIT treatment in children with intermittent or persistent AR is associated with lower symptom and medication scores in comparison with subjects treated with symptomatic drugs only.

The efficacy of sublingual immunotherapy for house dust mites respiratory allergy: results of a GA2LEN meta-analysis

Recent meta-analyses documented the efficacy and safety of sublingual immunotherapy (SLIT) in patients with allergic rhinitis (AR) and asthma (AA). Although SLIT appeared globally effective, the sub-analyses for single allergens provided uncertain results. This study is aimed to investigate the efficacy of SLIT with house dust mite (HDM) extracts in AR and AA through an updated reassessment of randomized controlled trials. Electronic databases were searched up to March 31, 2008, for randomized DBPC trials, assessing the efficacy of SLIT in AR and AA due to HDM sensitization. Outcomes were symptom scores and rescue medications use. For AR, eight studies fulfilled the selection criteria. A significant reduction in symptoms of AR (SMD -0.95; CI 95%-1.77 to -0.14 P = 0.02) was found in 194 patients (adults and children) receiving SLIT compared to 188 receiving placebo. For AA, with nine studies, similar results were found for symptoms (SMD -0.95; CI 95%-1.74 to -0.15 P = 0.02) in 243 patients (adults and children) receiving SLIT compared to 209 receiving placebo. A reduction in rescue medication use was found for AR (SMD -1.88; CI 95%-3.65 to -0.12 P = 0.04) in 89 patients, and AA (SMD -1.48; CI 95%-2.70 to -0.26 P = 0.02) in 202 patients. A relevant inter-study heterogeneity was detected. Promising evidence of efficacy for SLIT, using mite extract in allergic patients suffering from AR and AA, are herein shown. These findings suggest that more data are needed, derived from large-population-based high quality studies, and corroborated by objective outcomes, mainly for AA.

Recommendations for appropriate sublingual immunotherapy clinical trials

Sublingual immunotherapy is gaining widespread attention as a viable alternative to subcutaneous immunotherapy for the treatment of allergic rhinoconjunctivitis. In addition, sublingual immunotherapy has been studied in other allergic disorders including asthma. However, a review of published studies indicates that there are deficiencies and considerable heterogeneity in both design and data interpretation of sublingual immunotherapy studies. These deficiencies have made it somewhat difficult to assess the appropriate place of sublingual immunotherapy in guidelines for the therapy of allergic diseases. Moreover, several unpublished oral and sublingual immunotherapy studies in the United States failed to meet primary endpoints. This article reviews data from sublingual immunotherapy trials and makes recommendations about appropriate designs of future sublingual immunotherapy studies. It is hoped that these recommendations will result in more adequately designed sublingual immunotherapy trials to facilitate the appropriate placement of this therapy to treat patients with allergic rhinoconjunctivitis and other allergic diseases.

An update on the safety of specific immunotherapy

PURPOSE OF REVIEW

As allergen sublingual immunotherapy becomes more widely used in Europe and draws the attention of physicians of the USA, it is important to compare and contrast the safety aspects of this therapy versus allergen subcutaneous immunotherapy.

RECENT FINDINGS

There are reports of severe systemic reactions associated with sublingual immunotherapy, but no fatalities. There are various studies of systemic reactions, including those that result in death, associated with subcutaneous immunotherapy over its nearly 100-year worldwide experience. Local reactions are common to both forms of the treatment.

SUMMARY

If both forms of therapy are equally effective, a cost (including safety aspects) -benefit analysis of sublingual immunotherapy versus subcutaneous immunotherapy is necessary to determine how best to incorporate both forms of specific immunotherapy into the management of allergic patients. Adherence to published guidelines will reduce the likelihood of adverse reactions.

[Allergic rhinitis and its impact on asthma (ARIA update 2008). The Austrian perspective]

In 1999, during the ARIA (Allergic Rhinitis and its Impact on Asthma) WHO workshop, an evidence-based document was produced using an extensive review of the literature available up to December of the same year. An update of the ARIA guidelines was soon needed and started in 2004. Thereafter, there was the need for an even more global document, which would highlight the interactions between the upper and the lower airways including diagnosis, epidemiology, common risk factors, management and prevention, and comprise the allergy perspective also for developing countries. This goal was achieved with the most recently published ARIA update 2008. The present article is the result of consecutive efforts of the authors of the ARIA update 2008 to accomplish the nationwide comprehensive distribution of information by publication in important national journals, like the WMW.

Sublingual immunotherapy for allergic respiratory diseases: an evaluation of meta-analyses

BACKGROUND

Five published meta-analyses (MAs) seem to prove the efficacy of sublingual immunotherapy in allergic asthma and rhinoconjunctivitis.

OBJECTIVE

We aimed to assess the consistency, magnitude, and robustness of the results of these MAs.

METHODS

The data reported in the MAs were checked with the data reported in the original studies. Funnel plots were performed to test for potential publication bias, and the trim-and-fill method was used to assess and correct the estimate of the effects if asymmetry was present.

RESULTS

The 5 MAs included 43 studies; 17 were used in more than one MA. There were discrepancies among the MAs in the data reported from the same original studies: the MAs reported different estimates for the same outcome or the same estimates for different outcomes in 16 of those 17 studies. The MAs evaluated 15 main outcomes, 10 of which showed benefits that reached statistical significance. Funnel plots showed asymmetry in 7 outcomes, and correction by using the trim-and-fill method led to a decrease in their effect estimates and even to a loss of statistical significance in 4 of the previously significant outcomes. There was inconsistency among the MAs in the benefits when considering age, disease, allergen, or symptoms and medication use.

CONCLUSION

Because of discrepancies, inconsistencies, and lack of robustness, the MAs on sublingual immunotherapy do not provide enough evidence to support its current routine management in patients with allergic asthma or rhinoconjunctivitis. Sensitivity to potential publication bias should be tested and reported in all MAs.

Administration regimens for sublingual immunotherapy to pollen allergens: what do we know?

The modalities of administration of sublingual immunotherapy (SLIT), including dosing, build-up phase, duration of the treatment, and frequency of the maintenance dose are largely variable. In the case of pollen (SLIT), the complexity increases, since preseasonal, coseasonal and pre-coseasonal regimens can be used. The administration regimens are of relevance from a practical point of view, but can also have economic implications. We review herein the available literature (randomized double blind controlled studies) on pollen SLIT, in order to derive experimentally-supported suggestions about the regimens of administration that should be preferred.

Sublingual immunotherapy in children: complete and updated review supporting evidence of effect

PURPOSE OF REVIEW

The interest in sublingual immunotherapy (SLIT) is still growing worldwide and especially for the pediatric age group, this modality is appealing. Lately, some negative systematic review articles have been published on SLIT in children. However, high quality articles published from 2007 onward had not been included.

RECENT FINDINGS

Explanations are sought for the negative outcomes in these reviews and shortcomings are discussed. New pediatric studies - not included in the previous reviews -designed taking into account the golden rules for SLIT (high daily dose, starting at least 4 months before pollen season) do show statistically significant improvement in symptom and medication scores for rhinitis and asthma in pollen allergy. New house dust mite studies still show inconsistent data.

SUMMARY

Evidence of effect is confirmed for SLIT in children with allergic rhinitis or asthma caused by pollen exposure. For house dust mite asthma, evidence is still nonconcordant. New techniques to improve SLIT efficacy are under investigation.

Evaluation of serum s-IgE/total IgE ratio in predicting clinical response to allergen-specific immunotherapy

BACKGROUND

To date, no predictive tests for the clinical response to allergen-specific immunotherapy (ASI) are available. Therefore an in vivo or in vitro test would be of great value.

OBJECTIVE

We sought to evaluate pretreatment parameters used in diagnosing allergic rhinitis and determining serum specific IgE (s-IgE) levels, serum total IgE (t-IgE) levels, and blood eosinophil counts and to identify whether can be used to predict clinical improvement in monosensitized patients with allergic rhinitis with or without asthma treated with immunotherapy.

METHODS

We analyzed 279 patients who had undergone 4 years of ASI administered either by means of the subcutaneous immunotherapy (76 patients) or sublingual immunotherapy (203 patients) routes. Serum t-IgE and s-IgE levels, blood eosinophil counts, and serum s-IgE/t-IgE ratios were calculated and tested for correlation with clinical response to ASI. Receiver operating characteristic curves were determined. Predicted probabilities and predictive areas under the curve were calculated.

RESULTS

The clinical response to ASI was effective in 145 (52.0%) of 279 total patients, 42 (55.2%) of 76 patients treated with subcutaneous immunotherapy, and 103 (50.7%) of 203 patients treated with sublingual immunotherapy. A significant correlation was found between the serum s-IgE/t-IgE ratio and the clinical response to ASI, with high ratios (>16.2) associated with an effective response. The sensitivity and specificity of the area under the curve of the ratio were higher than those of serum s-IgE and t-IgE alone.

CONCLUSION

The calculation of the serum s-IgE/t-IgE ratio for predicting the clinical response to ASI offers an advantage over measuring t-IgE and s-IgE levels in monosensitized patients for the following allergens: grass, Parietaria judaica, Olea europea, and house dust mite.

Agreement of efficacy assessments for five-grass pollen sublingual tablet immunotherapy

BACKGROUND

The optimal dose of five-grass pollen sublingual tablet immunotherapy (SLIT) was established recently by the primary criteria Rhinoconjunctivitis Total Symptom Score (RTSS) from the first treatment season. Secondary and exploratory criteria, such as RTSS at peak pollen season, exploratory combined symptom and rescue medication use score, quality of life and immunological markers are calculated and described in this analysis.

METHODS

Six hundred and twenty-eight patients with grass pollen rhinoconjunctivitis (> or =2 years duration) were randomized in a double-blind, placebo-controlled trial conducted in Europe. Patients received once-daily SLIT (Stallergenes, Antony, France) of 100IR, 300IR, 500IR or placebo, starting 4 months before grass pollen season and throughout the 2005 season. Patients were instructed to take rescue medication only if symptoms were severe and record symptom severity on using the RTSS.

RESULTS

Both 300IR and 500IR doses significantly reduced mean RTSS at pollen peak (P = 0.0005 and P = 0.0014, respectively) and the exploratory combined score (P = 0.0001 and P = 0.0026, respectively) compared with placebo. Compared with patients in the placebo group, those who were taking the 300IR and 500IR doses reported significantly improved quality of life using the mean Rhinoconjunctivitis Quality of Life Questionnaire scores during the peak of the pollen season (P < 0.0001) and at the end of the pollen season (P = 0.0031 and P < or = 0.0001, respectively). Specific immunoglobulin G4 increased significantly depending on the SLIT dose (P < 0.0001).

CONCLUSIONS

All secondary efficacy criteria, including efficacy at pollen peak, combined score, quality of life and immunological changes, indicate that 300IR tablets represent the optimal dose and suggest it is appropriate for use in clinical practice.

Treatment of grass pollen allergy: focus on a standardized grass allergen extract - Grazax®

Immunotherapy is the only treatment for allergy that has the potential to alter the natural course of the disease. Sublingual immunotherapy (SLIT) for grass pollen-induced rhino-conjunctivitis has been developed to make immunotherapy available to a broader group of allergic patients. In the largest clinical programme ever conducted with allergen-specific immunotherapy, over 1,700 adults and 260 children have been exposed to Grazax(®). Grazax is formulated as an oral lyophilisate (tablet) for sublingual administration, containing 75,000 SQ-T standardized allergen extract of grass pollen from Phleum pratense. Grazax is indicated for treatment of grass pollen-induced rhinitis and conjunctivitis in adult patients with clinically relevant symptoms and diagnosed with a positive skin prick test and/or specific IgE test to grass pollen. In phase I trials doses from 2,500 to 1,000,000 SQ-T were tested. All doses were well tolerated and 75,000 SQ-T, with approximately 15 mug major allergen protein, was chosen as the optimal dose. Three phase III trials are ongoing, one being a long-term trial. Results from GT-08 trial first and second treatment years showed a reduction of 30% and 36%, respectively, in daily rhino-conjunctivitis symptom scores and a reduction of 38% and 46% of daily rhino-conjunctivitis medication scores compared with placebo over the entire grass pollen season. Subjects treated with Grazax also had an increased number of well days and improved quality of life, and more subjects experienced excellent rhino-conjunctivitis control. The most common adverse events related to Grazax are local reactions, such as pruritus, edema mouth, ear pruritus, throat irritation, and sneezing. We conclude that Grazax is efficacious and safe for treatment of rhino-conjunctivitis due to grass pollen allergy.

Randomized double-blind placebo-controlled trial of sublingual immunotherapy in children with house dust mite allergy in primary care: study design and recruitment

BACKGROUND

For respiratory allergic disorders in children, sublingual immunotherapy has been developed as an alternative to subcutaneous immunotherapy. Sublingual immunotherapy is more convenient, has a good safety profile and might be an attractive option for use in primary care. A randomized double-blind placebo-controlled study was designed to establish the efficacy of sublingual immunotherapy with house dust mite allergen compared to placebo treatment in 6 to 18-year-old children with allergic rhinitis and a proven house dust mite allergy in primary care. Described here are the methodology, recruitment phases, and main characteristics of the recruited children.

METHODS

Recruitment took place in September to December of 2005 and 2006. General practitioners (in south-west Netherlands) selected children who had ever been diagnosed with allergic rhinitis. Children and parents could respond to a postal invitation. Children who responded positively were screened by telephone using a nasal symptom score. After this screening, an inclusion visit took place during which a blood sample was taken for the RAST test.

RESULTS

A total of 226 general practitioners invited almost 6000 children: of these, 51% was male and 40% <12 years of age. The target sample size was 256 children; 251 patients were finally included. The most frequent reasons given for not participating were: absence or mildness of symptoms, absence of house dust mite allergy, and being allergic to grass pollen or tree pollen only. Asthma symptoms were reported by 37% of the children. Of the enrolled children, 71% was sensitized to both house dust mite and grass pollen. Roughly similar proportions of children were diagnosed as being sensitized to one, two, three or four common inhalant allergens.

CONCLUSION

Our study was designed in accordance with recent recommendations for research on establishing the efficacy of sublingual immunotherapy; 98% of the target sample size was achieved. This study is expected to provide useful information on sublingual immunotherapy with house dust mite allergen in primary care. The results on efficacy and safety are expected to be available by 2010.

TRIAL REGISTRATION

the trial is registered as ISRCTN91141483 (Dutch Trial Register).

New visions in specific immunotherapy in children: an iPAC summary and future trends

Specific immunotherapy is indicated for confirmed immunoglobulin E-mediated airway diseases using standardized allergen products with documented clinical efficacy and safety. For decades the subcutaneous route of administration (SCIT) has been the gold standard. Recently, the sublingual immunotherapy (SLIT) has also been investigated in children. SCIT, especially with grass and birch pollens but also house dust mites, is an effective treatment in children with allergic rhinitis and asthma when a significant part of their symptoms are caused by these allergens. A long-term effect up to 12 yr after discontinuation of SCIT with timothy allergen has been shown. Efficacy and safety of SLIT in pollen allergic rhinoconjunctivitis have been demonstrated in adults. The evidence in children is a little less convincing, and more data is needed. The clinical relevance, long-term results and the size of the effect, as well as the dose, the treatment regimen and duration has not been sufficiently elaborated. It is demonstrated that SCIT has the potential for preventing the development of asthma in children with allergic rhinoconjunctivitis. Also one randomized study indicates a preventive effect of SLIT in children on the development of asthma. At present, there are no studies who clearly demonstrates either a long-term effect or a preventive effect on the development of asthma of SLIT in children. The areas with lack of evidence should be addressed in well performed prospective, randomized long-term studies both with SCIT and SLIT. This review was initiated by iPAC (international Pediatric Allergy and Asthma Consortium) and aims to review current knowledge related to specific immunotherapy in childhood, and to identify needs for future research in this field.