Sub-lingual immunotherapy: world allergy organization position paper 2009

A brief history of allergen immunotherapy

Allergen immunotherapy has its roots in the immunologic treatment of contagious disease. The idea, beginning in the 18th century, that one could be protected against certain illnesses was successfully extended to the field of allergy in 1911. This review presents highlights of the advances by some of the individuals who have contributed to the science of allergen immunotherapy.

Sublingual immunotherapy for pediatric patients with mite allergies

Sublingual immunotherapy (SLIT) has been increasingly used instead of subcutaneous immunotherapy. SLIT was initially approved for use among adults; however, it has become more widely accepted for children. Few studies have evaluated the effectiveness of SLIT in the treatment of dust mite allergies among children, including adverse effects. This study aimed to investigate the effectiveness of SLIT in children with dust mite allergies, as well as its adverse effects, at a pediatric general outpatient clinic.I analyzed the data of 181 patients aged 4 to 12 years who tested positive for mite antigen-specific immunoglobulin E, exhibited nasal and/or eye symptoms, and received Miticure. Symptoms were evaluated using the Japanese rhino-conjunctivitis quality of life (QOL) questionnaire no. 1. Wilcoxon tests were used to compare the pretreatment and post-treatment symptom scores. Adverse events were tallied, and Kaplan-Meier curves and Wilcoxon tests were used to assess the proportion of dropouts.The mean QOL score at the baseline was 2.17 (standard deviation [SD] 1.45). After 1 week, the mean symptom QOL score was 1.63 (SD 1.32); the lowest mean score was found in week 41 (0.48, SD 0.63). A significant decline in the occurrence of all symptoms, including sneezing, nasal discharge, nasal congestion, itchy eyes, and teary eyes, was observed. Adverse effects were observed in 76 (42.0%) patients; the most common adverse effect was itchy mouth.SLIT improves symptoms with minimal adverse effects in pediatric patients.

Current possibilities and future perspectives for improving efficacy of allergen-specific sublingual immunotherapy

Allergen-specific sublingual immunotherapy (SLIT), a safe and efficient route for treating type I hypersensitivity disorders, requires high doses of allergens. SLIT is generally performed without adjuvants and delivery systems. Therefore, allergen formulation with appropriate presentation platforms results in improved allergen availability, targeting the immune cells, inducing regulatory immune responses, and enhancing immunotherapy's efficacy while decreasing the dose of the allergen. In this review, we discuss the adjuvants and delivery systems that have been applied as allergen-presentation platforms for SLIT. These adjuvants include TLRs ligands, 1α, 25-dihydroxy vitamin D3, galectin-9, probiotic and bacterial components that provoke allergen-specific helper type-1 T lymphocytes (TH1), and regulatory T cells (Tregs). Another approach is encapsulation or adsorption of the allergens into a particulate vector system to facilitate allergen capture by tolerogenic dendritic cells. Also, we proposed strategies to increasing the efficacy of SLIT via new immunopotentiators and carrier systems in the future.

Allergen immunotherapy: The growing role of observational and randomized trial "Real-World Evidence"

BACKGROUND

Although there is a considerable body of knowledge about allergen immunotherapy (AIT), there is a lack of data on the reliability of real-world evidence (RWE) in AIT, and consequently, a lack of information on how AIT effectively works in real life.

METHODS

To address the current unmet need for an appraisal of the quality of RWE in AIT, the European Academy of Allergy and Clinical Immunology Methodology Committee recently initiated a systematic review of observational studies of AIT, which will use the RELEVANT tool and the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE) to rate the quality of the evidence base as a whole. The next step will be to develop a broadly applicable, pragmatic "real-world" database using systematic data collection. Based on the current RWE base, and perspectives and recommendations of authorities and scientific societies, a hierarchy of RWE in AIT is proposed, which places pragmatic trials and registry data at the positions of highest level of evidence.

KEY RESULTS

There is a need to establish more AIT registries that collect data in a cohesive way, using standardized protocols.

CONCLUSIONS

This will provide an essential source of real-world data that can be easily shared, promoting evidence-based research and quality improvement in study design and clinical decision-making.

Efficacy and safety of intralymphatic immunotherapy in allergic rhinitis: A systematic review and meta-analysis

BACKGROUND

Intralymphatic immunotherapy (ILIT) is a potential treatment option for allergic rhinitis (AR). We aimed to determine the efficacy (primary outcomes) and safety (secondary outcomes) of ILIT in treating patients with AR.

METHODS

An electronic literature search was performed using MEDLINE and Cochrane Central Register of Controlled Trials CENTRAL (from their inception to December 2020). A random-effects model was used to estimate the pooled prevalence with 95% confidence intervals. This study is registered with PROSPERO (CRD42019126271).

RESULTS

We retrieved a total of 285 articles, of which 11 satisfied our inclusion criteria. There were 452 participants with age ranged from 15 to 58 years old. Intralymphatic immunotherapy was given in three doses with intervals of four weeks between doses in 10 trials. One trial gave three and six doses with an interval of two weeks. Both primary and secondary outcomes showed no difference between ILIT and placebo for all trials. There was no difference in the combined symptoms and medication score (SMD -0.51, 95% CI -1.31 to 0.28), symptoms score (SMD -0.27, 95% CI -0.91 to 0.38), medication score (SMD -6.56, 95% CI -21.48 to 8.37), rescue medication (RR 12.32, 95% CI 0.72-211.79) and the overall improvement score (MD -0.07, 95% CI -2.28 to 2.14) between ILIT and placebo. No major adverse events noted.

CONCLUSIONS

Intralymphatic immunotherapy possibly has a role in the treatment of AR patients. This review found it is safe but not effective, which could be contributed by the high variation amongst the trials. Future trials should involve larger numbers of participants and report standardized administration of ILIT and outcome measures.

Recent Advances in Allergen-Specific Immunotherapy as Treatment for Allergic Asthma: A Practical Overview

The Global Initiative for Asthma Report updated in 2019 stated that potential benefits of allergen immunotherapy (AIT), compared to pharmacological and avoidance options, must be weighed against the risk of adverse effects and the inconvenience and cost of the prolonged course of therapy in asthma. Thus, with the aim of clarifying some aspects with regard to the possible use of AIT in allergic asthma treatment armamentarium, a group of expert allergists from the Spanish Allergy and Clinical Immunology Scientific Society (SEAIC), particularly from the Immunotherapy and Asthma Interest Groups developed a frequently asked questions in clinical practice. This document updates relevant topics on the use of AIT in asthma and could facilitate physician clinical decisions and improve health outcomes for individual patients.

Artemisia Annua sublingual immunotherapy for seasonal allergic rhinitis: A multicenter, randomized trial

Background

Artemisia annua is the most common outdoor aeroallergen throughout Northern China; however, no multicenter study has investigated sublingual immunotherapy (SLIT) as a treatment option for Artemisia annua-induced allergic rhinitis (AR). The aim of this study was to evaluate the efficacy and safety of an innovative SLIT for Artemisia annua-related AR.

Methods

This was a randomized, double-blind, placebo-controlled, multicenter, phase 3 clinical trial conducted in China (NCT XXX). A total of 702 Artemisia annua-sensitized eligible patients were randomized in a ratio of 2:1 to receive Artemisia annua-SLIT or placebo. The treatment lasted 32 weeks; including 5-weeks up-dosing phase and 27-weeks maintenance phase. The primary endpoint was the daily combined score of medication and rhinoconjunctivitis symptom (CSMRS), and secondary endpoints were daily total nasal symptom score (dTNSS) and daily rescue medication score (dRMS) during peak pollen period. Safety of treatment was evaluated according to adverse events (AEs) experienced.

Results

Mean daily CSMRS was significantly improved during the peak pollen period in the SLIT group compared with the placebo group (1.46 ± 0.47 vs 1.88 ± 0.42, P < 0.0001 in full analysis set [FAS]; 1.49 ± 0.52 vs 1.95 ± 0.46, P < 0.0001 in per protocol set [PPS]); representing a 22.3% and 23.6% reduction, respectively, relative to placebo. In specifically Artemisia annua monosensitized patients, mean daily CSMRS reductions were demonstrated as 24.1% and 27.0% in the FAS and PPS populations, respectively, when comparing the active treatment to placebo treatment. Similarly, SLIT decreased dTNSS in peak pollen period by 19.0% in FAS and 22.3% in PPS, respectively, relative to placebo. In coincidence, dRMS in peak pollen period was reduced by 22.0% in FAS and 26.0% in PPS. 65.8% patients in SLIT group experienced treatment-related AEs, none of which was serious.

Conclusion

This study indicates that SLIT with Artemisia annua drops is an effective and safe treatment option in Chinese patients with Artemisia Annua-induced AR.

Artemisia annua-sublingual immunotherapy for seasonal allergic rhinitis: A randomized controlled trial

BACKGROUND

Artemisia annua is an important autumnal pollen allergen for seasonal allergic rhinitis (SAR) in northern China. To date, no study has investigated allergen immunotherapy with A annua. We aimed to investigate the efficacy and mechanisms underlying A annua-sublingual immunotherapy (SLIT).

METHODS

This was a randomized, double-blind, placebo-controlled phase III clinical trial involving 71 SAR patients, randomized to SLIT with A annua extract (n = 47) or placebo (n = 24) for 32 weeks. Total nasal symptom score (TNSS; primary clinical end point) was evaluated at baseline (peak pollen phase (PPP) in the previous year), initiation of A annua-SLIT, 1st PPP during SLIT, end of SLIT and 2nd PPP during follow-up. Blood samples and nasal secretions were collected at beginning and after SLIT for assessment of T cells and inflammatory mediators. Safety was assessed according to adverse events (AEs) reported.

RESULTS

Artemisia annua-SLIT significantly reduced TNSS to a greater level from baseline (from 9.45 ± 1.68 to 6.16 ± 2.27) than placebo (from 9.29 ± 2.09 to 9.05 ± 2.40) at the 1st PPP (P < .001) and sustained the improvement in symptoms throughout to the 2nd PPP. Preseasonal A annua-SLIT for 16 weeks significantly decreased Th2 cells, increased nTreg and Tr1 cells in blood; and increased cystatin 1 (CST1) in nasal secretion after 16 and 32 weeks compared with pretreatment. Overall, 17/47 patients experienced mild local AEs and 2 patients mild systemic AEs, after A annua-SLIT.

CONCLUSION

Artemisia annua-SLIT is an efficacious and safe treatment in patients with A annua SAR.

DC-targeted gold nanoparticles as an efficient and biocompatible carrier for modulating allergic responses in sublingual immunotherapy

BACKGROUND

Sublingual immunotherapy (SLIT) was introduced to deliver allergens in an effective and non-invasive route, which can be considered as an alternative for allergen-specific subcutaneous immunotherapy (SCIT). On the other hand, the use of gold nanoparticles (AuNPs) in allergen delivery has beneficial effects on sublingual immunotherapy. In addition, the molecular targeting agents like aptamers (Apt), have been widely applied for targeted drug delivery. Therefore, the current study aimed to evaluate the effects of dendritic cells (DCs)-specific Aptamer-modified AuNPs coated with ovalbumin (OVA) on the improvement of the SLIT outcome in the mouse model of allergy.

MATERIAL AND METHODS

AuNPs with approximately 15 nm diameter were prepared by citrate reduction of HAuCl4. Afterward, Apt-modified AuNP complex was prepared and OVA was then loaded onto this complex. Following sensitization of Balb/c mice to OVA, SLIT was performed with Apt-AuNPs containing 5 µg OVA twice a week for a 2-month period. Allergen-specific IgE in serum, as well as cytokines secretion of spleen cells, were analyzed using ELISA. Also, nasopharyngeal lavage Fluid (NALF) was collected for total and eosinophil counts. Moreover, the lungs were removed for histopathological examination.

RESULTS

SLIT with Apt-modified AuNPs complex containing 5 μg OVA, decreased the IgE levels compared to the other groups. Also, IL-4 production has significantly decreased in spleen cells, while TGF-β and IFN-γ have significantly increased. The assessment of NALF in the group treated by this complex showed a decrease in total cell as well as in eosinophil count. Also, the examination of lung tissues revealed that, in the group treated by this complex, inflammation and perivascular infiltration were lesser than the other groups, which were observed in only one vessel of tissue.

CONCLUSION

It was shown that, Sublingual immunotherapy with DC specific Apt-modified AuNPs containing 5 μg OVA can improve the Th1 and Treg immunomodulatory responses.

Impact on quality of life and safety of sublingual and subcutaneous immunotherapy in children with severe house dust mite and pollen-associated allergic rhinoconjunctivitis

Background

Pollen and house dust mite (HDM) subcutaneous immunotherapy (SLIT) and pollen subcutaneous immunotherapy (SCIT) are effective therapies for children with allergic rhinoconjunctivitis (AR). There are no previous direct comparative studies investigating quality of life (QoL) of all three immunotherapy regimes. The aim of this study was to compare QoL and safety in children receiving these immunotherapies for AR.

Methods

Demographic characteristics, Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) and Visual Analogue (VAS) scores were assessed in 249 children undergoing HDM and pollen immunotherapy at a UK specialist paediatric centre between 2007 and 2019.

Results

All three immunotherapy regimes led to a > 50% improvement in QoL and VAS after 3 years of therapy, with significant improvements by the end of the first year (p < 0.05) and further improvements between 1 and 3 years (p < 0.05). Age, gender, ethnicity and route of administration had no significant bearing on efficacy. Older, polysensitised children and those receiving HDM SLIT were all more likely to discontinue their treatment (all with p < 0.05). The only patient to suffer from anaphylaxis requiring intramuscular adrenaline, and 80% experiencing exacerbations of their asthma had received pollen SCIT.

Conclusions

Pollen SCIT and pollen and HDM SLIT all lead to significant improvements in QoL. The risk of anaphylaxis is low, but SCIT is associates with a 1 in 5 chance of asthma flares in the days after its administration. Discontinuation of therapy is more frequent in older, polysensitised children, and those undergoing HDM immunotherapy.

Efficacy and safety of SQ house dust mite sublingual immunotherapy-tablet in Japanese children

BACKGROUND

The SQ house dust mite (HDM) sublingual immunotherapy (SLIT)-tablet (TO-203, Torii, Japan/ALK, Denmark) treatment has been effective against respiratory allergic diseases in patients aged ≥12 years during European, Japanese, and North American trials. This trial was conducted to investigate the efficacy and safety of this treatment in Japanese children (5-17 years) with moderate-to-severe HDM allergic rhinitis (AR).

METHODS

In this randomized, double-blind, placebo-controlled trial, 458 Japanese children were randomly assigned to a daily SQ HDM SLIT-tablet [10 000 Japanese Allergy Unit (JAU), equivalent to 6 SQ-HDM in Europe and the US] or placebo (1:1) treatment for 1 year. Inclusion required an AR symptom score of ≥7 on at least 7 days during a 14-day run-in period while symptomatic treatment was withdrawn. The primary endpoint was the total combined rhinitis score (TCRS) comprising AR symptom and medication scores during the last 8 weeks of the treatment period.

RESULTS

The analysis of primary endpoint demonstrated statistically significant absolute reduction in TCRS of 1.22 with a relative difference of 23% (95% confidence interval, 14% to 31%) in the 10 000 JAU compared with placebo. Predefined stratified analyses revealed the same degree of efficacy of 1.11 (P = 0.002), 21% (8% to 32%) and 1.36 (P = 0.001), 26% (11% to 38%), respectively, in pediatric (5-11 years) and adolescent subjects (12-17 years). The treatment was well tolerated by both pediatric and adolescent subjects.

CONCLUSION

This trial, for the first time, demonstrated the efficacy and safety of the HDM SLIT-tablet in pediatric patients with moderate-to-severe HDM AR (JapicCTI-152953).

Development of the BELANA questionnaire for the analysis of economic burdens of food allergy and intolerance

INTRODUCTION

Patients affected by food allergies and intolerance need to apply dedicated avoidance strategies and also prevent the consequences of unbalanced diets. In most countries, the health economic costs for these patients are unknown.

METHODS

To measure temporal and financial burdens of the patients in multinational settings, the BELANA questionnaire (Burdens and Expenses of Living as an Adult with Nutrition based Allergy or Intolerance) has been developed. For the complementary measurement of Health Related Quality of Life (HR-QoL), a combined appliance of the disease-specific FAQLQ-AF (Food Allergy Quality of Life Questionnaire - Adult Form) and the generic SF-12v1 (Short Form-12 Health Survey) has been chosen.

RESULTS

BELANA collects six economic items while avoiding questions, which are already included in the HR-QoL questionnaires or could lead to denial tendencies. In a web-based pilot survey with 51 patients, the practicability of using BELANA together with the complementary quality of life instruments was investigated. The electronic data collection offers real time plausibility checks and limits the workload for completion and data evaluation.

DISCUSSION

The response rates at BELANA health-economic items (76 - 100%) and the high amount of completed questionnaires (50 of 51) confirm the patients acceptance of the chosen methodology. Within the web-based survey, the combination of BELANA, FAQLQ-AF and SF-12v1 was completed in an average of 22 minutes. An age-related selection bias was not been confirmed in this pilot application. The median age in the pilot trial was 37.9 years (minimum age to participate was 18 years, range from 19 to 72 years, Standard Deviation (SD) = 12.4 years). Most of the participants were female (44 of 50).

CONCLUSION

It is assumed that the BELANA questionnaire should be a useful tool for the evaluation of health-economic burden for patients with food allergy and intolerance.

SQ house dust mite sublingual immunotherapy tablet subgroup efficacy and local application site reaction duration

BACKGROUND

Allergic rhinitis with or without conjunctivitis (AR/C) is common, necessitating evaluation of SQ house dust mite (HDM) sublingual immunotherapy (SLIT)-tablet efficacy in various subgroups.

OBJECTIVE

To evaluate 12 SQ-HDM efficacy and safety across subgroups, and the onset, duration, and recurrence of local application site reactions.

METHODS

Subgroup (age, sex, race, asthma status, and allergen sensitization) efficacy was assessed using pooled data from 2 previously described trials of daily 12 SQ-HDM vs placebo for AR/C (n = 2,138). Efficacy was measured by average total combined rhinitis score (TCRS; rhinitis daily symptom plus medication score) during the last 8 weeks of treatment. Safety in subgroups and local application site reaction onset, duration, and recurrence were evaluated using pooled data from 5 previously described trials of SQ HDM SLIT-tablet (n = 2,923).

RESULTS

Significant (based on 95% confidence intervals [CIs]) reduction in TCRS was seen with 12 SQ-HDM relative to placebo across all subgroups, with TCRS improvements ranging from 15% to 25%. The AE profile was generally similar within subgroups. Approximately 95% of local application site reactions were mild to moderate in severity. Median duration on day 1 of treatment for the most common local application site reactions (throat irritation, oral pruritus, ear pruritus, and lip swelling) ranged from 30 to 60 minutes; median first day of onset ranged from days 1 to 4 of treatment; median days that reactions recurred ranged from 3 to 12 days.

CONCLUSION

Treatment with 12 SQ-HDM consistently improved symptoms and was well tolerated in relevant subgroups of subjects with HDM AR/C. Local application site reactions to 12 SQ-HDM were typically mild to moderate and transient.

Applicability of evidence from previous systematic reviews on immunotherapy in current practice of childhood asthma treatment: a GRADE (Grading of Recommendations Assessment, Development and Evaluation) systematic review

OBJECTIVE

Because most children with asthma now use inhaled corticosteroids (ICS), the added benefit of immunotherapy in asthmatic children needs to be examined. We re-assessed the effectiveness of subcutaneous (SCIT) and sublingual immunotherapy (SLIT) in childhood asthma treatment focusing on studies with patient-relevant outcome measures and children using ICS.

METHODS

We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to systematically search and appraise the evidence using predefined critical patient-relevant outcomes (asthma symptoms, asthma control and exacerbations). We searched to retrieve systematic reviews and randomised controlled trials on immunotherapy for asthma in children (1960-2017). We assessed the quality of the body of evidence with GRADE criteria.

RESULTS

The quality of the evidence for SCIT was very low due to a large risk of bias and indirectness (dated studies in children not using ICS). No effect of SCIT was found for asthma symptoms; no studies reported on asthma control. For asthma exacerbations, studies favoured SCIT. We have little confidence in this effect estimate, due to the very low quality of evidence. For SLIT, quality of the evidence was very low due to a large risk of bias, indirectness and imprecision. The outcome 'asthma symptoms' could not be calculated due to lack of standardisation and large clinical heterogeneity. Other predefined outcomes were not reported.

CONCLUSION

The beneficial effects of immunotherapy in childhood asthma found in earlier reviews are no longer considered applicable, because of indirectness (studies performed in children not being treated according to current asthma guidelines with ICS). There was absence of evidence to properly determine the effectiveness or lack thereof of immunotherapy in asthma treatment in children with ICS.

Biological mechanisms underlying the clinical effects of allergen-specific immunotherapy in asthmatic children

INTRODUCTION

Allergen-specific immunotherapy (AIT) is indicated for patients with allergic asthma and/or allergic rhinitis, and can be implemented by either subcutaneous injection (SCIT) or sublingual administration (SLIT). AIT reduces asthma symptoms, lowers the use of pharmacologic controller therapy, and decreases the need for rescue medications. SLIT appears to be safer than SCIT, but SCIT seems to be more efficacious and acts earlier in allergic asthmatic children.

AREAS COVERED

This review looks at the pathobiology of allergic asthma as well as the role of regulatory T and B cells in allergen tolerance. It also reviews the immunological mechanisms underlying the clinical effects induced by AIT in allergic asthmatic children.

EXPERT OPINION

AIT is very effective in allergic asthmatic children, who can significantly benefit from this particular type of immunotherapy in order to achieve a better control of their disease. AIT is also capable of modifying the natural history of allergic asthma. Furthermore, AIT can potentially represent a valuable therapeutic tool within the context of precision medicine, as recombinant allergen technology might allow the creation of targeted extracts able to be effective against specific proteins to which individual asthmatic children are allergic, thus helping to implement a personalized approach to treatment.

Chinese Guideline on allergen immunotherapy for allergic rhinitis

The present document is based on a consensus reached by a panel of experts from Chinese Society of Allergy (CSA) and Chinese Allergic Rhinitis Collaborative Research Group (C2AR2G). Allergen immunotherapy (AIT), has increasingly been used as a treatment for allergic rhinitis (AR) globally, as it has been shown to provide a long-term effect in improving nasal and ocular symptoms, reducing medication need, and improving quality of life. AIT is currently the only curative intervention that can potentially modify the immune system in individuals suffering from AR and prevent the development of new sensitization and the progression of disease from AR to asthma. Although the use of AIT is becoming more acceptable in China, to date no AR immunotherapy guideline from China is available for use by the international community. This document has thus been produced and covers the main aspects of AIT undertaken in China; including selection of patients for AIT, the allergen extracts available on the Chinese market, schedules and doses of allergen employed in different routes of AIT, assessment of effect and safety, patients' administration and follow-up, and management of adverse reactions. The Chinese guideline for AR immunotherapy will thus serve as a reference point by doctors, healthcare professionals and organizations involved in the AIT of AR in China. Moreover, this guideline will serve as a source of information for the international community on AIT treatment strategies employed in China.

Utility and Comparative Efficacy of Recombinant Allergens Versus Allergen Extract

Allergy immunotherapy (AIT) is the only disease-modifying therapy for the treatment of allergic diseases. Although its efficacy and utility are well-established, the potential for serious adverse events, cumbersome and lengthy treatment protocols, and variability of natural allergen preparations have limited its widespread application. Recent advances in recombinant technology have opened new avenues for the development of AIT vaccines. The purpose of this review is to highlight recent evidence on the use of novel recombinant vaccines and review the mechanisms, efficacy, safety, and limitations of AIT. Emerging evidence suggests that recombinant vaccines may provide a viable treatment alternative that improves on the limitations of natural extract therapy while maintaining efficacy.

[Adherence in specific immunotherapy]

Allergies are steadily gaining in importance in the Western world. For over one hundred years, immunology has been the only causal treatment. Specific immunotherapy (SIT) aims at the cure of allergy or at least freedom from allergy symptoms. In association with this, adherence poses a complex problem. Both treatment applications commonly used in Germany-sublingual and subcutaneous immunotherapy-show poor persistence on the part of the patients. In most cases, SIT is not carried out to the end of the recommended duration and instead is discontinued prematurely. Corresponding figures from 3‑year studies in the literature range from 41- 93% for uncompleted SLIT and from 40-77% for uncompleted SCIT. Patient adherence is subject to influencing factors of various dimensions that are interdependent in complex relationships. The physician-patient relationship is just as decisive a factor for treatment success as the patient's understanding of allergy, treatment, and the importance of adherence.

Effectiveness of Specific Sublingual Immunotherapy in Korean Patients with Atopic Dermatitis

Background

Sublingual immunotherapy (SLIT) with house dust mites (HDM) preparation has recently been proven to be beneficial for treating allergic rhinitis and asthma. However, there has been no report regarding the efficacy and safety of SLIT in Korean patients with atopic dermatitis (AD).

Objective

We intended to investigate the efficacy and safety of SLIT in Korean patients with AD.

Methods

A total of 34 patients with AD and immunoglobulin E (IgE)-proven HDM sensitization (Class ≥3) were recruited. Eczema area and severity index (EASI) score, total serum IgE level, specific IgE assays to Dermatophagoides pteronyssinus, D. farinae, and adverse effects were recorded during follow-up. "Responder" was defined as a patient with ≥30% improvement in EASI score after SLIT.

Results

Twenty-three patients continued SLIT for 12 months or more, whereas 3 patients (8.8%) dropped out because of exacerbation of dermatitis, and 8 patients (23.5%) were lost to follow-up. The average duration of SLIT treatment was 22.4 months (range, 12~32 months). EASI scores reduced significantly after 6 months of treatment (p<0.05) compared with those at baseline. A total of 18 patients were determined to be responders to SLIT after 6 months. Total and specific IgE serum levels did not significantly reduce after SLIT. No patients experienced serious adverse events, with the exception of two patients who developed transient lip and tongue swelling.

Conclusion

Our study demonstrated that SLIT with HDM extracts is effective and tolerable in Korean patients with AD. Further controlled long-term trials are required to reinforce the current results.

Subcutaneous and Sublingual Immunotherapy in Allergic Asthma in Children

This review presents up-to-date understanding of immunotherapy in the treatment of children with allergic asthma. The principal types of allergen immunotherapy (AIT) are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). Both of them are indicated for patients with allergic rhinitis and/or asthma, who have evidence of clinically relevant allergen-specific IgE, and significant symptoms despite reasonable avoidance measures and/or maximal medical therapy. Studies have shown a significant decrease in asthma symptom scores and in the use of rescue medication, and a preventive effect on asthma onset. Although the safety profile of SLIT appears to be better than SCIT, the results of some studies and meta-analyses suggest that the efficacy of SCIT is better and that SCIT has an earlier onset than SLIT in children with allergic asthma. Severe, not controlled asthma, and medical error were the most frequent causes of SCIT-induced adverse events.

Sublingual versus subcutaneous immunotherapy: patient adherence at a large German allergy center

BACKGROUND

Many placebo-controlled studies have demonstrated that allergen immunotherapy (AIT) is an effective therapy for treating allergies. Both commonly used routes, subcutaneous (SCIT) and sublingual immunotherapy (SLIT), require high patient adherence to be successful. In the literature, numbers describing adherence vary widely; this investigation compares these two routes of therapy directly.

METHODS

All data were retrieved from the patient data management system of a center for dermatology, specific allergology, and environmental medicine in Germany. All 330 patients (aged 13-89 years) included in this study had commenced AIT between 2003 and 2011, thus allowing a full 3-year AIT cycle to be considered for each investigated patient.

RESULTS

In this specific center, SCIT was prescribed to 62.7% and SLIT to 37.3% of all included patients. The total dropout rate of the whole patient cohort was 34.8%. Overall, SLIT patients showed a higher dropout rate (39.0%) than did SCIT patients (32.4%); however, the difference between these groups was not significant. Also, no significant difference between the overall dropout rates for men and for women was observed. A Kaplan-Meier curve of the patient collective showed a remarkably high dropout rate for the first year of therapy.

CONCLUSION

The analysis presented in this single-center study shows that most patients who discontinue AIT do so during the first year of therapy. Patients seem likely to finish the 3-year therapy cycle if they manage to adhere to treatment throughout the first year. Strategies for preventing nonadherence in AIT, therefore, need to be developed and standardized in future investigations.

Efficacy and safety of SQ house dust mite (HDM) SLIT-tablet treatment of HDM allergic asthma

INTRODUCTION

In the treatment of house dust mite (HDM) respiratory allergic disease, allergy immunotherapy constitutes an add-on treatment option targeting the underlying immunological mechanisms of allergic disease. However, for the treatment of HDM allergic asthma, the use of subcutaneous allergy immunotherapy (SCIT) has been limited by the risk of systemic adverse events. Thus, sublingually administered allergy immunotherapy (SLIT) has been investigated as a treatment option with an improved tolerability profile that allows for safer treatment of patients with HDM allergic asthma.

AREAS COVERED

In this Drug Profile, we provide a review of the clinical data behind the SQ HDM SLIT-tablet, which was recently approved for the treatment of HDM allergic asthma and allergic rhinitis by regulatory authorities in several European countries. Expert commentary: The SQ HDM SLIT-tablet is the first allergy immunotherapy to be tested prospectively in patients with asthma, and to favorably modify patient relevant end points such as requirement for inhaled corticosteroid (ICS) or the time to first asthma exacerbation upon ICS reduction, suggesting that SQ HDM SLIT-tablet treatment may contribute to improving overall asthma control.

The efficiency of peptide immunotherapy for respiratory allergy

Allergen immunotherapy (AIT) was introduced more than a century ago and is yet the only disease-modifying treatment for allergy. AIT is currently conducted with whole allergen extracts and several studies clearly support its efficacy in the treatment of respiratory allergies, however the need for a long treatment - that affects costs and patients compliance - and possible IgE-mediated adverse events are still unresolved issues. Peptide immunotherapy is based on the use of short synthetic peptides which represent major T-cell epitopes of the allergen with markedly reduced ability to cross-link IgE and activate mast cells and basophils. Data from clinical trials confirmed the efficacy and tolerability of peptide immunotherapy in patients with cat allergy, with a sustained clinical effect after a short course treatment. Peptide therapy is a promising safe and effective new specific treatment for allergy to be developed for the most important allergens causing rhinitis or asthma.

Orphan immunotherapies for allergic diseases

OBJECTIVE

As confirmed by systematic reviews and meta-analyses, allergen immunotherapy is clinically effective in the treatment of allergic diseases. In particular, subcutaneous immunotherapy is a pivotal treatment in patients with severe reactions to Hymenoptera venom, whereas subcutaneous immunotherapy and sublingual immunotherapy are indicated in the treatment of allergic rhinitis and asthma by inhalant allergens. Other allergies related to animal dander (other than cat, which is the most studied), such as dog, molds, occupational allergens, and insects, have also been recognized. For these allergens, immunotherapy is poorly studied and often unavailable. Thus, use of the term orphan immunotherapies is appropriate.

DATA SOURCES

We used MEDLINE to search the medical literature for English-language articles.

STUDY SELECTION

Randomized, controlled, masked studies for orphan immunotherapies were selected. In the remaining cases, the available reports were described.

RESULTS

The literature on food desensitization is abundant, but for other orphan allergens, such as mosquito, Argas reflexus, dog, or occupational allergens, there are only a few studies, and most are small studies or case reports.

CONCLUSION

Orphan immunotherapy is associated with insufficient evidence of efficacy from controlled trials, an erroneous belief of the limited importance of some allergen sources, and the unlikelihood for producers to have a profit in making commercially available extracts (with an expensive process for registration) to be used in few patients. It should be taken into consideration that adequate preparations should be available also for orphan allergens.

Clinical and immunological responses of dust mite sensitive, atopic dogs to treatment with sublingual immunotherapy (SLIT)

BACKGROUND

Sublingual immunotherapy (SLIT) has been reported to be beneficial in people with atopic dermatitis (AD) and dust mite sensitivity. Evaluation of this therapy has not been reported in spontaneous canine AD.

OBJECTIVES

The objective of this study was to preliminarily evaluate the effectiveness of an established SLIT protocol, as used in human patients, in dogs with AD.

ANIMALS

Ten dust mite sensitive dogs with spontaneous AD.

METHODS

Dogs underwent a 6 month open trial of SLIT concurrently with decreasing dose oral methylprednisolone. Clinical evaluations and quantitative serum anti-mite IgE and IgG levels were performed every 2 months.

RESULTS

Mean methylprednisolone use from the first 2 months of the study to the final 2 months declined from 10.2 to 4.3 mg/kg/2 months (P < 0.001, Student's paired t-test); at 6 months, four dogs required no oral corticosteroid administration. Over the course of the study, median Canine Atopic Dermatitis Extent and Severity Index (CADESI)-03 scores declined from 76.5 to 59; median pruritus scores declined from 65 to 37 (P < 0.02 and P < 0.01, respectively; Wilcoxon signed-rank test). Pre- and post-SLIT intradermal test scores for mite allergen were not significantly different over time. Median Dermatophagoides farinae (DF)-specific IgE levels declined significantly from 150.2 × 10(3) AU/mL to 3.6 × 10(3) AU/mL (P < 0.05). Concurrently, median DF-specific IgG levels increased from 18.5 × 10(6) AU/mL to 3923.4 × 10(6) AU/mL (P < 0.05; Wilcoxon signed-rank tests).

CONCLUSIONS AND CLINICAL IMPORTANCE

SLIT treatment produced clinical improvement in dogs with dust mite-associated AD and was associated with serological changes supporting this improvement. Further studies in larger numbers of dogs and those with polysensitization are warranted.

Critical appraisal of Timothy grass pollen extract GRAZAX in the management of allergic rhinitis

Allergic rhinitis is one of the most common diseases of adult and pediatric age, associated with grass pollen (GP) allergy in >50% cases, with a consistent impact on quality of life of affected patients. A grass allergen tablet, containing standardized extract derived from Timothy grass (Phleum pratense) pollen and ~15 μg major allergen P. pratense (rPhl p 5), may be the future of allergen-specific immunotherapy (IT) for GP allergy. The aim of this review was to critically evaluate the role of Timothy GP extract IT for the management of allergic rhinitis. For this purpose, we have tried to analyze potential mechanisms of action at the basis of Timothy GP extract, we have reviewed efficacy studies to establish potential benefits and clinical response, and we have also evaluated safety and tolerability profiles and patient focus perspective, such as quality of life, satisfaction and acceptability, and compliance to this IT.

The Future of Sublingual Immunotherapy in the United States

Sublingual immunotherapy (SLIT) is a safe and effective treatment for allergic rhinitis (AR) and allergic rhinoconjunctivitis (ARC). The Food and Drug Administration (FDA) in the USA has approved three SLIT tablets for the treatment of AR and ARC in relation to pollen. Specifically, Grastek® and Oralair® are two formulations approved to treat patients suffering with AR/ARC to grass pollen, and Ragwitek™ is a formulation approved to treat patients suffering with AR/ARC to ragweed pollen. Although these approvals provide support for physicians to prescribe SLIT, barriers to prescribing SLIT still remain such as FDA approval for additional formulations, a standard dose and dosing schedule, and cost/insurance coverage. In order to further support the use of SLIT, research is currently being conducted to expand the indication for SLIT to other common comorbidities to AR/ARC. For example, allergic asthma, food allergies, and atopic dermatitis are other diseases which are being explored. The future of SLIT in the USA is unknown; however, education will be necessary for both providers and patients.

Vaccination with different doses of Dermatophagoides farinae in a mouse model of allergic asthma

BACKGROUND

The efficacy of vaccination with different doses of a vaccine has not been clarified. The purpose of this study was to investigate the relationship between the doses of purified house dust mite allergen, and allergic airway inflammation and airway reactivity in a mouse model of allergic asthma.

METHODS

C57BL/6 mice were sensitized with Dermatophagoides farinae (Der f) and randomly treated with saline, 0.1, 1, or 2 mg Der f vaccine, respectively. The airway hyperresponsiveness, the numbers of total cells and eosinophils and the levels of interferon-γ and interleukin (IL)-4 in the bronchoalveolar lavage fluid (BALF) from individual mice were measured. The percentages of CD11c CD86 and CD11c MHC II+ dendritic cells were characterized, and the levels of IL-12 in the supernatants of cultured dendritic cells were measured.

RESULTS

The airway hyperresponsiveness, the numbers of total cells and eosinophils in the BALF and the percentages of CD11c CD86 and CD11c MHC II+ dendritic cells were associated with immunologic downregulation. The levels of IFN-γ in the BALF and the levels of IL-12 in the supernatants of cultured dendritic cells were associated with immunologic upregulation. It was found that vaccination with the medium dose of Der f showed a stronger inhibitory effect.

CONCLUSIONS

There seems to be a dose-dependent response between allergen and both airway inflammation and hyperreactivity in the mouse model of allergic asthma.

Immunoglobulin E and Allergy: Antibodies in Immune Inflammation and Treatment

The pathogenic role of immunoglobulin E (IgE) antibodies in triggering and maintaining allergic inflammation in response to allergens is due to the binding of multivalent allergens to allergen-specific IgEs on sensitized effector cells. These interactions trigger effector cell activation, resulting in release of potent inflammatory mediators, recruitment of inflammatory cells, antigen presentation, and production of allergen-specific antibody responses. Since its discovery in the 1960s, the central role of IgE in allergic disease has been intensively studied, placing IgE and its functions at the heart of therapeutic efforts for the treatment of allergies. Here, we provide an overview of the nature, roles, and significance of IgE antibodies in allergic diseases, infections, and inflammation and the utility of antibodies as therapies. We place special emphasis on allergen-IgE-Fcε receptor complexes in the context of allergic and inflammatory diseases and describe strategies, including monoclonal antibodies, aimed at interrupting these complexes. Of clinical significance, one antibody, omalizumab, is presently in clinical use and works by preventing formation of IgE-Fcε receptor interactions. Active immunotherapy approaches with allergens and allergen derivatives have also demonstrated clinical benefits for patients with allergic diseases. These treatments are strongly associated with serum increases of IgE-neutralizing antibodies and feature a notable redirection of humoral responses towards production of antibodies of the IgG4 subclass in patients receiving immunotherapies. Lastly, we provide a new perspective on the rise of recombinant antibodies of the IgE class recognizing tumor-associated antigens, and we discuss the potential utility of tumor antigen-specific IgE antibodies to direct potent IgE-driven immune responses against tumors.

Effective treatment of house dust mite-induced allergic rhinitis with 2 doses of the SQ HDM SLIT-tablet: Results from a randomized, double-blind, placebo-controlled phase III trial

BACKGROUND

The SQ HDM SLIT-tablet (ALK) has been developed for treatment of house dust mite (HDM)-induced respiratory allergic disease.

OBJECTIVE

This trial investigated the efficacy and safety of the SQ HDM SLIT-tablet in adults with moderate-to-severe HDM-induced allergic rhinitis (AR).

METHODS

The trial was a randomized, double-blind, placebo-controlled phase III trial conducted in 12 European countries including 992 adults with moderate-to-severe HDM-induced AR despite treatment with pharmacotherapy. Subjects were randomized 1:1:1 to 1 year of daily treatment with placebo, 6 SQ-HDM, or 12 SQ-HDM. The primary end point was the total combined rhinitis score (ie, the sum of rhinitis symptom and medication scores) during the efficacy assessment period (approximately the last 8 weeks of the treatment period). Key secondary end points were rhinitis symptoms, medication scores, quality of life, and the combined rhinoconjunctivitis score.

RESULTS

Analysis of the primary end point (observed data) demonstrated absolute reductions in total combined rhinitis score of 1.18 (P = .002) and 1.22 (P = .001) compared with placebo for 6 SQ-HDM and 12 SQ-HDM, respectively. The statistically significant treatment effect was evident from 14 weeks of treatment onward. For all key secondary end points, efficacy was confirmed for 12 SQ-HDM, with statistically significant reductions of rhinitis symptoms and medication scores, improved quality of life, and a reduced combined rhinoconjunctivitis score in the efficacy assessment period compared with placebo. The treatment was well tolerated.

CONCLUSION

The trial confirmed the efficacy and favorable safety profile of both 6 SQ-HDM and 12 SQ-HDM in adults with HDM-induced AR. The treatment effect was present from 14 weeks of treatment onward.

Facing Hymenoptera Venom Allergy: From Natural to Recombinant Allergens

Along with food and drug allergic reactions, a Hymenoptera insect Sting (Apoidea, Vespidae, Formicidae) is one of the most common causes of anaphylaxis worldwide. Diagnoses of Hymenoptera venom allergy (HVA) and specific immunotherapy (SIT) have been based on the use of crude venom extracts. However, the incidence of cross-reactivity and low levels of sensibility during diagnosis, as well as the occurrence of nonspecific sensitization and undesired side effects during SIT, encourage the search for novel allergenic materials. Recombinant allergens are an interesting approach to improve allergy diagnosis and SIT because they circumvent major problems associated with the use of crude venom. Production of recombinant allergens depends on the profound molecular characterization of the natural counterpart by combining some “omics” approaches with high-throughput screening techniques and the selection of an appropriate system for heterologous expression. To date, several clinically relevant allergens and novel venom toxins have been identified, cloned and characterized, enabling a better understanding of the whole allergenic and envenoming processes. Here, we review recent findings on identification, molecular characterization and recombinant expression of Hymenoptera venom allergens and on the evaluation of these heterologous proteins as valuable tools for tackling remaining pitfalls on HVA diagnosis and immunotherapy.

Negative clinical results from a randomised, double-blind, placebo-controlled trial evaluating the efficacy of two doses of immunologically enhanced, grass subcutaneous immunotherapy despite dose-dependent immunological response

OBJECTIVE

Specific immunotherapy is the only treatment for the underlying allergic disease in patients with respiratory allergies. The primary objective of this trial was to evaluate the efficacy and safety of two maintenance doses of immunologically enhanced, standardised quality (SQ+) grass subcutaneous immunotherapy (SCIT) [4,000 SQ+ and 15,000 SQ+; AVANZ(®) Phleum pratense (ALK)] compared with placebo.

METHODS

This was a randomised, double-blind, placebo-controlled, phase II/III trial. The primary evaluation was based on the combined rhinoconjunctivitis score during the entire grass pollen season. Adult subjects with grass pollen-induced allergic rhinoconjunctivitis interfering with usual activities or sleep despite symptomatic medication use, were enrolled.

RESULTS

Four hundred and fifty subjects were randomised to receive either 4,000 SQ+ (n = 150), 15,000 SQ+ (n = 152) or placebo (n = 148). The average grass pollen exposure was 27 grains/m(3)/day. No statistically significant differences between the active groups and the placebo group were found for clinical endpoints (p > 0.05). Highly statistically significant (p < 0.001) increases in IgG4 and IgE-blocking factor were found for both active groups versus placebo. The most frequently reported adverse events were mild-to-moderate local injection-site reactions; events were generally more frequent with 15,000 SQ+ than with 4,000 SQ+ and placebo. The most common adverse events leading to premature discontinuation from the trial were anaphylactic reactions (one subject from the placebo group and five subjects from the 15,000 SQ+ group).

CONCLUSIONS

The inconclusive results were most probably influenced by a very low grass pollen season. Other factors such as the extent of the pre-seasonal treatment could potentially have contributed. The tolerability profile was acceptable for further development.

Arguing the misconceptions in allergen-specific immunotherapy

Allergen immunotherapy (AIT) has a clear evidence of efficacy and safety, as shown by a number of meta-analyses. However, a number of issues limit the use of AIT, many of them being not actually supported by solid data from the literature. In particular, several contraindications to AIT deserve to be argued, being needed to accurately balance in single cases the benefits versus the disadvantages. This concerns comorbidities, such as autoimmune diseases and malignancies, concomitant drug treatments, particularly β-blockers and angiotensin-converting enzyme inhibitors, pregnancy, patient's age, the severity of asthma, allergen polysensitization and the period of starting the treatment. Another important aspect producing misconceptions on AIT is the quality of the allergen extracts, because currently a patient with respiratory allergy to a given source may be prescribed to treat his allergyby products with very different quality. Improving characterization and standardization of allergen extracts will pave the way to the general acknowledgment of AIT as an effective treatment.

Immunotherapy in all aspects

Allergen immunotherapy is a form of long-term treatment that decreases symptoms for many people with allergic rhinitis, allergic asthma, conjunctivitis (eye allergy) or stinging insect allergy. In this review, we presented the important topics in immunotherapy. The important aspects of immunotherapy are considered to be "Immunologıcal responses to immunotherapy"; "The principal types of immunotherapy"; "Effectiveness"; "Indications"; "Contraindications"; "Allergen immunotherapy in children"; "Safety"; and "Anaphylactic reactions after immunotherapy". The principal types of immunotherapy are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy. Both of them can be used in indicated cases. When using SCIT, physicians must be more careful because of reported rare fatal cases. The risks and benefits of continuing allergen immunotherapy in patients who have experienced severe systemic reactions should be carefully considered.

Role of immunotherapy in the treatment of allergic asthma

Allergen-specific immunotherapy (SIT) induces clinical and immunological tolerance as defined by persistence of clinical benefit and associated long-term immunological parameters after cessation of treatment. Although the efficacy of SIT has been shown in terms of reducing symptoms, medication consumption and ameliorating quality of life in both allergic rhinitis and asthma, there has long been some controversies about effectiveness of SIT in the treatment of allergic asthma. The type of allergen, the dose and protocol of immunotherapy, patient selection criteria, the severity and control of asthma, all are significant contributors to the power of efficacy in allergic asthma. The initiation of SIT in allergic asthma should be considered in case of coexisting of other allergic diseases such as allergic rhinitis, unacceptable adverse effects of medications, patient’s preference to avoid long-term pharmacotherapy. Steroid sparing effect of SIT in allergic asthma is also an important benefit particularly in patients who have to use these drugs in high doses for a long-time. Symptomatic asthma is a risk factor for systemic reactions and asthma should be controlled at the time of administration of SIT. Both subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) have been found to be effective in patients with allergic asthma. Although the safety profile of SLIT seems to be better than SCIT, the results of some studies and meta-analyses suggest that the efficacy of SCIT may appear better and earlier than SLIT in children with allergic asthma.

Current status and future perspectives of immunotherapy in Latin America and Cuba

Most Latin-American countries use subcutaneous immunotherapy (SCIT) extracts from the United States and Europe and sublingual immunotherapy (SLIT) from Europe, with the exception of Argentina, Brazil, Cuba and Mexico. The number of researches on immunotherapy (IT) in Latin America has increased extensively in the last years. Only few Latin American countries have their own guidelines on IT, and, in general, the economic resources for medical research on IT are still low in the area. A global approach for the future of IT in Latin America includes to improve standardization, quality control and the production of allergen products, to develop IT guidelines and clinical investigation by the highest number of countries, to improve the regulatory status for allergens products in the area, and to expand IT accessibility for low-income patients. In Cuba, the first registered allergen vaccines were developed and registered in 2006: a standardized (in biologic units) and freeze dried product for SCIT, with a sublingual version developed in 2009. As much as 23.000 IT treatments were applied in 2011, all provided to patients free of charge. In 2012, Cuban researchers developed an IT vaccine with adjuvant for subcutaneous route, which uses Neisseria meningitidis proteoliposome as an adjuvant, added to the purified Dermatophagoides siboney major allergens: Der s1 and Der s2. Since December 2012, this vaccine is in Phase I clinical trial, evaluating its safety, tolerability and immunogenicity in asthmatic patients sensitized to this allergen. Cuban perspectives on IT includes to work on new indications for IT, to investigate the preventive effect and cost-effectiveness for the current vaccines, to develop new products with mixed formulas of house dust mites for SLIT, to complete the phase I and II clinical study for dust mite plus adjuvant vaccine, to develop allergen vaccines for fungi allergy and to complete the Cuban guideline for allergen IT management.

Efficacy and safety of ragweed sublingual immunotherapy in Canadian patients with allergic rhinoconjunctivitis

Background

Currently accepted therapies for ragweed allergy in North America consist of pharmacotherapy and subcutaneous allergen immunotherapy injections to treat symptoms. Allergen immunotherapy not only reduces symptoms and the need for pharmacotherapy but has also been shown to have disease-modifying potential. Recently, ragweed immunotherapy administered via sublingual allergen tablet has been approved in North America for treatment of allergic rhinitis with and without conjunctivitis.

Methods

This was an analysis of pooled data for a prespecified subgroup of Canadian subjects from two multicentre, randomized, double-blind placebo-controlled trials of ragweed sublingual tablet (SLIT-T; 6 and 12 Amb a 1-U of Ambrosia artemisiifolia) in patients aged ≥18y, with ragweed-induced allergic rhinoconjunctivitis (AR/C) with or without asthma. Randomized subjects used once-daily ragweed SLIT-T or placebo for at least 12 weeks before the ragweed season and for up to 52 weeks post-randomization. The primary efficacy endpoint was the total combined score (TCS) based on the sum of AR/C daily symptom score (DSS) and daily medication score (DMS) averaged over the peak season. Treatment effects on TCS, DSS, and DMS in the entire season were also assessed. Adverse events (AEs) were monitored to assess safety.

Results

337 Canadian subjects were randomized in the two trials. During the peak season, ragweed SLIT-T 6 and 12 Amb a 1-U significantly reduced TCS by 26% (difference, -2.46 score point; p = .0009) and 40% (difference, -3.75 score point; p < .0001), respectively. In the overall population (N = 961), TCS reductions with 6 and 12 Amb a 1-U were 20% and 23%, respectively (both p < .001). Clinically meaningful reductions in entire-season TCS in Canadians were similar to those during peak ragweed season. Dose-dependent reduction of DSS and DMS was also observed for ragweed SLIT-T 6 and 12 Amb a 1-U during the peak season and the entire season. Ragweed SLIT-T was well tolerated in Canadian subjects and the overall population. Adverse events were generally mild to moderate and transient, occurring early in treatment; no systemic allergic reaction/anaphylaxis was noted.

Conclusion

Ragweed SLIT-T is an effective form of immunotherapy that provides symptomatic efficacy of AR/C with a favorable risk profile in Canadian and overall populations.

Trial registration

Clinicaltrials.gov identifiers NCT00783198 and NCT00770315.

The efficacy and safety of the Timothy grass allergy sublingual immunotherapy tablet in Canadian adults and children

BACKGROUND

The effect of sublingual Timothy grass immunotherapy tablet 2800 BAU (grass SLIT-T) has been evaluated in three North American trials in adults and children who have allergic rhinitis with or without conjunctivitis (AR/C). This paper examines the effects of grass SLIT-T in Canadians.

METHODS

Data for grass-allergic Canadians in three randomized, placebo-controlled, double-blind trials were analyzed post hoc: 1) adults ≥18 y, grass-pollen season [GPS] 2009; 2) children 5- <18 y, 2009; and 3) adults 18-65 y and children 5- <18 y, GPS 2012. Data from the GPS 2009 trials were pooled to provide a more precise estimate of treatment effects than the individual studies would provide. In every trial, participants received once-daily grass SLIT-T or placebo approximately 12 weeks before and continuing throughout the GPS. Participants used daily electronic diaries to record AR/C symptoms and medication use for treatment of symptoms. The therapeutic effect of grass SLIT-T was measured as a total combined score (TCS = daily symptom score + daily medication score) averaged over the entire GPS. Safety was assessed by monitoring adverse events (AEs).

RESULTS

In the three trials, 386 Canadian participants were randomized; the overall population had 2284 participants. Canadian participants treated with grass SLIT-T in the pooled adult-pediatric 2009 trials showed a 38% mean TCS reduction relative to placebo (-2.06 difference [95% CI: -3.72, -0.39]; 3.32 vs. 5.37). Participants treated with grass SLIT-T in the adult-pediatric 2012 trial showed a 37% median TCS reduction relative to placebo (-1.53 difference [95% CI: -2.1, -0.3]; 2.58 vs. 4.11). Similar efficacy findings were observed over the peak GPS. Approximately 90% of treatment-related AEs were mild or moderate in severity. Two Canadian participants had moderate systemic allergic reactions (skin, respiratory, abdominal symptoms) to grass SLIT-T; symptoms resolved within 1 hour without medical intervention or treatment. No serious or life-threatening treatment-related AEs occurred.

CONCLUSION

The 2800 BAU Timothy grass SLIT-T significantly improved AR/C induced by Timothy grass pollen in adults and children ≥5 y in Canadians, which was consistent with the robust efficacy observed in the overall trial population. The treatment was generally well tolerated.

TRIAL REGISTRATION

Clinicaltrials.gov identifiers NCT00562159, NCT00550550, NCT01385371.

Patient initiation and persistence with allergen immunotherapy

BACKGROUND

Allergen immunotherapy (AIT) is advised for patients with allergic rhinitis who remain symptomatic despite the use of pharmacotherapy and allergen avoidance. Several factors influence the decision to initiate and complete the AIT regimen.

OBJECTIVE

To evaluate patient initiation and persistence with subcutaneous and sublingual immunotherapies (SCIT and SLIT) according to physician recommendation.

METHODS

A retrospective review of electronic health records of patients with allergic rhinitis for whom AIT was recommended was conducted in a large private allergy practice in Pennsylvania.

RESULTS

Of 8,790 patients advised to consider AIT, 36.2% initiated AIT (57% adults, 43% children); 78% chose SCIT and 22% chose SLIT drops. Election of AIT was significantly associated with select comorbidities, specifically chronic sinusitis (8.1% for AIT vs 10% for no AIT), allergic conjunctivitis (12.5% for AIT vs 18.5% for no AIT), and asthma (33.8% for AIT vs 37.4% for no AIT; P < .05). Choice of SCIT vs SLIT drops was significantly associated with older age, female sex, select comorbidities, and more allergy medications at initiation (P < .05). Of adults, 30.2% completed at least 3 years of recommended treatment. Median time on treatment was longer for adults on SCIT vs SLIT drops (3 vs 1.6 years). Similarly, 35.4% of children completed treatment, with a longer median time on treatment for SCIT (4.7 years) vs SLIT drops (3.5 years).

CONCLUSION

A minority of patients initiated AIT according to allergist recommendation and a subset of these patients completed therapy. AIT might be an underused option that could benefit patients unable to manage allergic rhinitis symptoms by other means.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01549340.

Magnitude of efficacy measurements in grass allergy immunotherapy trials is highly dependent on pollen exposure

Background

The objective was to evaluate the association between grass pollen exposure, allergy symptoms and impact on measured treatment effect after grass sublingual immunotherapy (SLIT)-tablet treatment.

Methods

The association between grass pollen counts and total combined rhinoconjunctivitis symptom and medication score (TCS) was based on a post hoc analysis of data collected over six trials and seven grass pollen seasons across North America and Europe, including 2363 subjects treated with grass SLIT-tablet or placebo. Daily pollen counts were obtained from centralized pollen databases. The effect of treatment on the relationship between the TCS and pollen counts was investigated, and the relative difference between grass SLIT-tablet and placebo as a function of average grass pollen counts was modelled by linear regression.

Results

The magnitude of treatment effect based on TCS was greater with higher pollen exposure (P < 0.001). The relative treatment effect in terms of TCS for each trial was correlated with the average grass pollen exposure during the first period of the season, with predicted reduction in TCS = 12% + 0.35% × pollen count (slope significantly different from 0, P = 0.003; R² = 0.66). Corresponding correlations to the entire grass pollen season and to the peak season were equally good, whereas there was a poor correlation between difference in measured efficacy and pollen exposure during the last part of the season.

Conclusions

In seasonal allergy trials with grass SLIT-tablet, the observed treatment effect is highly dependent on pollen exposure with the magnitude being greater with higher pollen exposure. This is an important relationship to consider when interpreting individual clinical trial results.

Sublingual immunotherapy: World Allergy Organization position paper 2013 update

We have prepared this document, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2013 Update", according to the evidence-based criteria, revising and updating chapters of the originally published paper, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2009", available at http://www.waojournal.org. Namely, these comprise: "Mechanisms of sublingual immunotherapy;" "Clinical efficacy of sublingual immunotherapy" - reporting all the data of all controlled trials published after 2009; "Safety of sublingual immunotherapy" - with the recently published Grading System for adverse reactions; "Impact of sublingual immunotherapy on the natural history of respiratory allergy" - with the relevant evidences published since 2009; "Efficacy of SLIT in children" - with detailed analysis of all the studies; "Definition of SLIT patient selection" - reporting the criteria for eligibility to sublingual immunotherapy; "The future of immunotherapy in the community care setting"; "Methodology of clinical trials according to the current scientific and regulatory standards"; and "Guideline development: from evidence-based medicine to patients' views" - including the evolution of the methods to make clinical recommendations.Additionally, we have added new chapters to cover a few emerging crucial topics: "Practical aspects of schedules and dosages and counseling for adherence" - which is crucial in clinical practice for all treatments; "Perspectives and new approaches" - including recombinant allergens, adjuvants, modified allergens, and the concept of validity of the single products. Furthermore, "Raising public awareness about sublingual immunotherapy", as a need for our patients, and strategies to increase awareness of allergen immunotherapy (AIT) among patients, the medical community, all healthcare stakeholders, and public opinion, are also reported in detail.

Allergen immunotherapy for house dust mite: clinical efficacy and immunological mechanisms in allergic rhinitis and asthma

INTRODUCTION

There is an increasing prevalence of atopic diseases such as allergic rhinitis and asthma with house dust mite (HDM) being the common allergen that is highly associated with allergic rhinitis and asthma. Allergen avoidance and pharmacotherapy are part of treatment but it has proved difficult to change the course of HDM-related allergic diseases. Allergen immunotherapy (AIT) has been in use for the past century and has been shown to be effective in the treatment of allergic respiratory disease.

AREAS COVERED

This review exclusively focuses on HDM-AIT and discusses the differences in clinical efficacy and safety, long-term effect after discontinuation and immunological changes observed in both HDM-subcutaneous immunotherapy (SCIT) and HDM-sublingual immunotherapy (SLIT) in the treatment of allergic rhinitis and asthma in both pediatric and adult populations.

EXPERT OPINION

The majority of studies involved small numbers of patients, variable doses of major allergens and are of variable quality. There is good evidence for HDM-SCIT efficacy and its long-term effect in adults and children, whereas at the present time, evidence for HDM-SLIT is unconvincing, particularly in children. In carefully selected patients, HDM-SCIT is effective and safe. More definitive trials are needed before HDM-SLIT can be recommended in routine practice for rhinitis and/or asthma.

Allergen immunotherapy: routes, safety, efficacy, and mode of action

Allergic rhinitis, allergic conjunctivitis, and allergic asthma have been steadily increasing in prevalence in recent years. These allergic diseases have a major impact on quality of life and are a major economic burden in the US. Although allergen avoidance and pharmacotherapy are currently the mainstays of therapy, they are not always successful in treating patients' symptoms effectively. If a patient fails allergen avoidance and medical therapy, immunotherapy may be indicated. Furthermore, immunotherapy is the only therapy that may change the course of the disease and induce long-term remission. Though subcutaneous administration has been the standard route for immunotherapy for many decades, there are several other routes of administration that have been and are currently being studied. The goal of utilizing alternative routes of immunotherapy is to improve safety without decreasing the efficacy of treatment. This paper will review the novel routes of immunotherapy, including sublingual, oral, local nasal, epicutaneous, and intralymphatic.