Accelerated immunotherapy schedules: review of efficacy and safety

Oral immunotherapy with enteric-coated capsules for allergic rhinitis caused by house dust mites

Background

Oral immunotherapy (OIT) is a promising allergen-specific approach in the management of food allergy; however, studies on OIT for allergic rhinitis (AR) have rarely been reported. The purpose of this study is to evaluate the efficacy and safety of OIT using enteric-coated capsules for AR induced by house dust mites.

Methods

A total of 49 patients with AR were enrolled, including 25 who received subcutaneous immunotherapy (SCIT) and 24 who received OIT. The clinical efficacy and safety in both groups were evaluated.

Results

After 1 year of treatment, both SCIT and OIT demonstrated significant therapeutic effects. OIT was found to be more effective than SCIT in reducing the total AR symptom score and improving the results of nasal provocation tests. Local and systemic adverse reactions were observed in the SCIT group, while none were reported in the OIT group.

Conclusion

OIT is an effective and safe treatment for mite-induced AR.

Clinical and experimental treatment of allergic asthma with an emphasis on allergen immunotherapy and its mechanisms

Allergen immunotherapy (AIT) is currently the only form of treatment that modifies allergic asthma. Pharmacotherapy alone seeks to control the symptoms of allergic asthma, allergic rhinitis, and other atopic conditions. In contrast, AIT can induce long-term physiological modifications through the immune system. AIT enables individuals to live improved lives many years after treatment ends, where they are desensitized to the allergen(s) used or no longer have significant allergic reactions upon allergen provocation. The leading forms of treatment with AIT involve injections of allergen extracts with increasing doses via the subcutaneous route or drops/tablets via the sublingual route for several years. Since the initial attempts at this treatment as early as 1911 by Leonard Noon, the mechanisms by which AIT operates remain unclear. This literature-based review provides the primary care practitioner with a current understanding of the mechanisms of AIT, including its treatment safety, protocols, and long-term efficacy. The primary mechanisms underlying AIT include changes in immunoglobulin classes (IgA, IgE, and IgG), immunosuppressive regulatory T-cell induction, helper T cell type 2 to helper T cell type 1 cell/cytokine profile shifts, decreased early-phase reaction activity and mediators, and increased production of IL-10, IL-35, TGF-β, and IFN-γ. Using the databases PubMed and Embase, a selective literature search was conducted searching for English, full-text, reviews published between 2015 and 2022 using the keywords (with wildcards) "allerg*," "immunotherap*," "mechanis*," and "asthma." Among the cited references, additional references were identified using a manual search.

Nondaily dosing schedule of allergen-specific sublingual immunotherapy: efficacy and safety

Purpose

Sublingual immunotherapy is currently promoted by various companies, with administration schedules variable in the different products even though almost all are standardized immunologically. So, this study was planned to examine the efficacy of simple nondaily dosing of sublingual immunotherapy instead of the widely used daily schedule.

Materials and Methods

Fifty-two patients with allergic rhinitis and bronchial asthma were enrolled. Sublingual immunotherapy (manufactured at the allergen immunotherapy preparation unit at Mansoura University) was given in suitable bottles with a dropper mechanism that permits comfortable dosing under the tongue. The physician recommended that the patient put the drops under his/her tongue and leave the drops beneath the tongue for 2 minutes before swallowing. This was repeated every 3 days, with the drop number and concentration gradually rising.

Results

After 2 months of follow-up, 65.8% responded partially to the symptom score and 26.3% responded completely to the medication score. There was a significant decline in the symptom and medication scores from the baseline scores (p<0.0001). After 4 months of follow-up, 95.8% responded partially to symptom scores and no one has not responded; 54.2% responded completely to medication scores; and 81% of studied patients had no side effects. However, the most frequent side effect was a sore throat.

Conclusion

Our nondaily schedule of sublingual immunotherapy is tolerable, safe, and effective in patients with allergic rhinitis and bronchial asthma.

Chinese Guideline on Allergen Immunotherapy for Allergic Rhinitis: The 2022 Update

In the last few decades, there has been a progressive increase in the prevalence of allergic rhinitis (AR) in China, where it now affects approximately 250 million people. AR prevention and treatment include allergen avoidance, pharmacotherapy, allergen immunotherapy (AIT), and patient education, among which AIT is the only curative intervention. AIT targets the disease etiology and may potentially modify the immune system as well as induce allergen-specific immune tolerance in patients with AR. In 2017, a team of experts from the Chinese Society of Allergy (CSA) and the Chinese Allergic Rhinitis Collaborative Research Group (C2AR2G) produced the first English version of Chinese AIT guidelines for AR. Since then, there has been considerable progress in basic research of and clinical practice for AIT, especially regarding the role of follicular regulatory T (TFR) cells in the pathogenesis of AR and the use of allergen-specific immunoglobulin E (sIgE) in nasal secretions for the diagnosis of AR. Additionally, potential biomarkers, including TFR cells, sIgG4, and sIgE, have been used to monitor the incidence and progression of AR. Moreover, there has been a novel understanding of AIT during the coronavirus disease 2019 pandemic. Hence, there was an urgent need to update the AIT guideline for AR by a team of experts from CSA and C2AR2G. This document aims to serve as professional reference material on AIT for AR treatment in China, thus improving the development of AIT across the world.

A real-world retrospective study of safety, efficacy, compliance and cost of combination treatment with rush immunotherapy plus one dose of pretreatment anti-IgE in Chinese children with respiratory allergies

Background

The efficacy of allergen immunotherapy (AIT) in treating pediatric allergy has been clearly demonstrated, however, many patients hesitate to initiate AIT due to weekly hospital visits during the 3-4 months up-dosing phase. Meanwhile, rush immunotherapy (RIT) shortens the duration of the up-dosing phase to 7 days. However, considering that patients receiving RIT are exposed to the allergens during a much shorter period of time and thus may be at a greater risk of systemic reactions, RIT is currently underused, especially in children. This study investigated the utility of combination treatment with RIT plus 1 dose of pretreatment anti-IgE in children with respiratory allergies.

Methods

In this retrospective study, we reviewed records of children with allergic rhinitis (AR) and/or allergic asthma (AA) sensitized to dust mite allergens receiving RIT+1 dose of pretreatment anti-IgE (the RIT group) or conventional immunotherapy (the CIT group) at our hospital from January 2020 to March 2021. Data such as visual analogue scale (VAS) scores, comprehensive symptom and medication score (CSMS), allergy blood test results, adverse reactions, compliance and cost were collected and analyzed.

Results

40 patients in the RIT group and 81 patients in the CIT group were included in this study. Both treatments were well tolerated and patients in the 2 treatment groups had comparable local and systemic reactions. Compared to CIT, RIT + anti-IgE combination led to significantly faster symptomatic improvement as demonstrated by significantly decreased VAS and CSMS starting as early as 1 month after AIT initiation (P&lt;0.05). Nobody dropped out in the RIT group during the 1 year follow-up, while 11 out of 81 patients in the CIT group dropped out (loss rate 13.5%). Thus, the RIT group had a significantly higher compliance rate than the CIT group (P&lt;0.05). Finally, the 2 treatment regimens had comparable cost per patient per injection (P&gt; 0.05).

Conclusions

RIT + 1 dose of pretreatment anti-IgE combination has practical advantages over CIT, including comparable safety, better compliance, and probably a faster onset of clinical efficacy at no additional cost, so it can be an useful regimen for the treatment of Chinese children with respiratory allergies.

Accelerated/rush allergen immunotherapy

Accelerated allergy shot schedules for inhalant and venom allergens provide individuals with allergy symptom relief but in a shorter time frame than conventional therapy. Accelerated immunotherapy (IT) protocols allow patients to reach therapeutic doses in a shorter time frame while improving adherence and reducing direct costs (e.g., fewer office visits and medications) and indirect costs (e.g., less travel time, missed work or school). Rush IT and cluster IT are believed to work through mechanisms similar to conventional subcutaneous IT (SCIT). The risk for severe systemic reactions during accelerated IT is low when appropriately administered; however, life-threatening and fatal reactions do occur. To reduce the incidence of systemic allergic reactions during cluster and rush IT protocols, premedication is recommended. It is important to exclude individuals at high risk such as those with poorly controlled asthma or those who are on β-blockers to mitigate the risk for developing systemic allergic reactions. However, accelerated SCIT regimens offer increased convenience, faster improvement in allergy symptoms, and the potential to reduce health-care costs while providing equivalent safety outcomes compared with conventional IT protocols.

Allergen Immunotherapy in Asthma

Allergen immunotherapy (AIT) is a specific treatment involving the administration of relevant allergens to allergic patients, with subtypes including subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT). In asthma, AIT using the house dust mite (HDM) alleviates clinical symptoms and decreases airway hyper responsiveness and medication dose. In addition, AIT can improve the natural course of asthma. For example, the effects of AIT can be preserved for at least a few years, even after ending treatment. AIT may increase the remission rate of asthma in children and suppress sensitization to new allergens. If AIT is introduced in pollinosis, AIT may prevent the development of asthma. Moreover, AIT can control other allergic diseases complicated by asthma, such as allergic rhinitis, which also improves the control of asthma. The indication of HDM-SCIT for asthma is mild-to-moderate HDM-sensitized allergic asthma in a patient with normal respiratory function. To date, HDM-SLIT is applicable in Japan for allergic rhinitis, not for asthma. However, the effect of SLIT on asthma has been confirmed internationally, and SLIT is available for asthma in Japan if allergic rhinitis is present as a complication.

Clinical evaluation of rush immunotherapy using house dust mite allergen in Japanese asthmatics

Background

Allergen immunotherapy (AIT) is a specific treatment of administering clinically important allergens to patients who have allergic diseases. In Japan, the standardized house dust mite (HDM) allergen for subcutaneous immunotherapy (SCIT) was approved in 2015, and we then introduced rush-immunotherapy (rush-IT) using the standardized HDM allergen for HDM-sensitive asthmatics. However, little data are available on the safety and effectiveness of rush-HDM-IT, especially for Japanese asthmatics.

Objective

The objective of this study was to examine the safety and clinical effectiveness of rush-IT using the standardized HDM for HDM-sensitive Japanese asthmatics.

Methods

Thirteen HDM-sensitive asthmatics who received rush-HDM-IT and 12 HDM-sensitive asthmatic controls were enrolled. To evaluate the safety, the number of systemic reaction (SR) events, including anaphylaxis, was assessed. To evaluate the effectiveness, changes in the treatment step, dose of inhaled corticosteroid, and asthma control after rush-HDM-IT and the subsequent maintenance SCIT were assessed. Changes in the HDM-induced production of type 2 cytokines from peripheral blood mononuclear cells were also evaluated.

Results

Among the 12 patients who received rush-IT, 4 (30.7%) experienced a SR and 3 (23.1%) experienced anaphylaxis. However, the anaphylaxis was not severe (grade 3) in all cases, and they recovered in a short time. The treatment step of asthma was better and the dose of inhaled corticosteroid was lower in the rush-HDM-IT group than in the control group. The HDM-induced production of both interleukin (IL)-5 and IL-13 from peripheral blood mononuclear cells was significantly lower in the rush-HDM-IT group than in the control group.

Conclusion

Rush-HDM-IT can be performed relatively safely in Japanese asthmatics. Furthermore, rush-HDM-IT and the subsequent maintenance SCIT provided clinical improvement in asthma patients, and was accompanied by the suppression of HDM-specific Th2-mediated systemic immune responses.

Early Efficacy Analysis of Cluster and Conventional Immunotherapy in Patients With Allergic Rhinitis

BACKGROUND

Specific immunotherapy is an important immune-modifying treatment for patients with allergic rhinitis (AR). We compared the early efficacy and safety of cluster and conventional immunotherapies for patients with AR.

METHODS

One hundred forty-nine patients with persistent AR were enrolled in a randomized and open-label trial and were divided into the following 4 groups: 60 children treated conventionally, 33 children treated using the cluster schedule, 23 adults treated conventionally, and 33 adults treated using the cluster schedule. Patients in the cluster groups reached the maintenance dose within 6 weeks, while those receiving conventional therapy reached the maintenance dose within 14 weeks. Symptom scores and skin prick test scores (SPTs) were used to evaluate clinical efficacy and adverse reactions.

RESULTS

After buildup phase of treatment, symptom scores, and SPTs were significantly lower than those prior to treatment in each group (P < .05). No significant differences were found in the efficacy of nasal symptoms scores among four groups (P > .05).However, the efficacy of SPTs using conventional schedule was higher than cluster schedule in children groups (group A and B, 57.7 vs 30.2%, P = .001). Besides, the efficacy of SPTs in adults was higher than children when using the cluster treatment (group D and B, 53.0 vs 30.2%, P = .008). No severe adverse reaction occurred.

CONCLUSIONS

Conventional and cluster immunotherapy schedules have similar efficacies, which do not vary with age; both schedules are safe and reliable. Also, SPT facilitate evaluation of clinical efficacy.

Tolerability and surrogate efficacy parameters of a polymerized depot mixture pollen extracts without dilutional effect

Aim: To evaluate tolerability of subcutaneous immunotherapy, in a polymerized mixture (Olea europaea/Phleum pratense) depot presentation. Patients & methods: A total of 47 poly-allergic patients received: an abbreviated schedule with three injections at weekly intervals or a cluster schedule with two administrations in 1 day. Both treatments continued with 3 monthly maintenance administrations. Results: Two systemic reactions, (4.3%). One grade 0 and one grade I. No local reactions. Immunoglobulin levels, increased significantly at final visit versus baseline in sIgG and sIgG4; in both schedules and allergens, no significant changes in specific immunoglobulin E levels were detected. Cutaneous reactivity at final visit decreased significantly. Conclusion: Both administration schedules with polymerized mixture of O. europaea/P. pratense, presented an excellent tolerability profile and induced preliminary efficacy changes.

Shortened up-dosing with sublingual immunotherapy drops containing tree allergens is well tolerated and elicits dose-dependent clinical effects during the first pollen season

Background

This study compared a rapid home-based up-dosing schedule for sublingual immunotherapy (SLIT) drops containing tree pollen allergens with two previously established schedules. Furthermore, the clinical effect of the SLIT was investigated with respect to patients’ first pollen season under treatment.

Methods

In this open-label, prospective, patient-preference, non-interventional study, local and systemic reactions were compared between three up-dosing groups using a SLIT formulation containing birch, alder, and hazel pollen extracts (ORALVAC^® Compact Bäume). Clinical improvement after patients’ first season under treatment was analysed using symptom scores, ARIA classification, symptom control, and the use of symptomatic medication and was compared with data from the previous, pre-treatment pollen season. As the real-life study design allowed no placebo group, the late-treated patients (co-seasonal) served as a control, and crowd-sourced symptom data from persons with hay fever were used from a free web-based online diary.

Results

In 33 study centres in Germany and Austria, 164 patients were included. The treatment was well tolerated, without difference between the groups during the up-dosing phase. At the end of the assessment, 96.1% rated the tolerability of the treatment as good or very good. Local reactions were mostly mild in severity and no serious adverse events occurred. Symptom scores decreased from the 2016 pollen season to the 2017 pollen season. As for the ARIA classification, 79.0% of patients had persistent, moderate-to-severe rhinitis before treatment, but only 18.6% had the same classification after treatment. In all, 62.4% of patients achieved symptom control, and 34.3% of patients required no symptomatic medication after treatment. The rhinoconjunctivitis score was 34.4% lower for pre-seasonal treatment initiation than for the control group. Crowd-sourced symptom load indices showed that the 2016 season caused slightly more symptoms; however, it is assumed that this difference of 0.3–0.5 (score range 0–10) was of less clinical relevance.

Conclusion

The treatment administered using the rapid home-based up-dosing schedule was safe and well tolerated. Symptom relief and reduction in medication use were observed during the first pollen season with SLIT.

Trial registration number

NCT03097432 (clinicaltrials.gov).

Persistent regulatory T-cell response 2 years after 3 years of grass tablet SLIT: Links to reduced eosinophil counts, sIgE levels, and clinical benefit

Background

In the first 2 years of grass tablet sublingual immunotherapy treatment, we have previously demonstrated a progressive development of a regulatory T‐cell response, which was preceded by an early decrease in the frequency of both IL‐4+ cells and sIgE levels. A progressive increase in sIgG₄ levels and FAB blockage were also found.

Methods

By monitoring immunological kinetics during 3 years of active treatment + 2 years of follow‐up, we aimed to identify key immunological parameters that could explain sustained clinical benefit of grass tablet sublingual immunotherapy.

Results

Thirty patients completed the 5‐year clinical trial protocol. Although individual responses were heterogeneous, reduction in both sIgE and circulating IL‐4+ cells compared to the initial 1‐ to 4‐month peak was maintained throughout the 3‐year treatment period and for 2 years after discontinuation. Meanwhile, after a 2‐year increase in sIgG4, the levels were stabilized during the third year and decreased post‐therapy. FAB inhibition remained significantly inhibited throughout the study compared to preimmunotherapy in 83% of patients. A sustained regulatory T‐cell response, after IT cessation, occurs in two‐thirds of the patients. There was a statistical association between this regulatory response, the maintenance of lower eosinophil counts during grass pollen seasons, and sIgE titers lower than before immunotherapy treatment, and the latter were significantly associated with clinical response.

Conclusion

Our results suggest that the immunological mechanisms underlying the sustained response after 2 years of cessation of immunotherapy (3‐year treatment period) are linked to the acquisition and maintenance of a regulatory T‐cell response.

Safety of Ultra-rush Schedule of Subcutaneous Allergen Immunotherapy With House Dust Mite Extract Conducted in an Outpatient Clinic in Patients With Atopic Dermatitis and Allergic Rhinitis

Purpose

Ultra-rush schedule of subcutaneous allergen immunotherapy (UR-SCIT) administering maximum maintenance dose of allergen extract within one day can save time and effort for allergen immunotherapy in patients with allergic disease. However, UR-SCIT is associated with an increased risk of systemic reaction (SR) and typically has been conducted in a hospital admission setting. To overcome disadvantages of UR-SCIT, we evaluated the safety of UR-SCIT conducted in an outpatient clinic in patients with atopic dermatitis (AD) and allergic rhinitis (AR).

Methods

UR-SCIT was performed in 538 patients with AD and/or AR sensitized to house dust mite (HDM). A maximum maintenance dose of tyrosine-adsorbed HDM extract (1 mL of maintenance concentration) was divided into 4 increasing doses (0.1, 0.2, 0.3, and 0.4 mL) and administered to the patients by subcutaneous injection at 2-hour intervals for 8 hours in an outpatient clinic. SRs associated with UR-SCIT were classified according to the World Allergy Organization grading system.

Results

SR was observed in 12 of 538 patients (2.2%) with AD and/or AR during UR-SCIT. The severity grades of the observed SRs were mild-to-moderate (grade 1 in 7 patients, grade 2 in 4 patients, and grade 3 in 1 patient). The scheduled 4 increasing doses of HDM extract could be administered in 535 of 538 patients (99.4%) except 3 patients who experienced SR before administration of the last scheduled dose. SR was observed within 2 hours in 11 patients after administration of the scheduled doses of HDM extract except one patient who experienced a grade 2 SR at 5.5 hours after administration of the last scheduled dose.

Conclusions

UR-SCIT with tyrosine-adsorbed HDM extract conducted in an outpatient clinic was tolerable in patients with AD and AR. UR-SCIT can be a useful method to start a SCIT in patients with AD and AR.

New approaches to allergen immunotherapy

OBJECTIVE

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

DATA SOURCES

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

STUDY SELECTIONS

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

RESULTS

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

CONCLUSION

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

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.

Managing anaphylaxis in the office setting

BACKGROUND

Although the definition of anaphylaxis for clinical use may vary by professional health care organizations and individuals, the definition consistently includes the concepts of a serious, generalized or systemic, allergic or hypersensitivity reaction that can be life-threatening or even fatal.

METHODS

In this review, we presented the important topics in the treatment of anaphylaxis in the office setting. This review will discuss triggers and risk factors, clinical diagnosis, and management of anaphylaxis in the office setting.

RESULTS

Anaphylaxis in the office setting is a medical emergency. It, therefore, is important to prepare for it, to have a posted, written anaphylaxis emergency protocol, and to rehearse the plan regularly. In this review, we presented the important steps in managing anaphylaxis in the office. Treatment of anaphylaxis should start with epinephrine administered intramuscularly at the first sign of anaphylaxis. Oxygen and intravenous fluids may be needed for moderate-to-severe anaphylaxis or anaphylaxis that is quickly developing or if the patient is unresponsive to the first injection of epinephrine. Antihistamine therapy is considered adjunctive to epinephrine, which mainly relieves itching and urticaria. Corticosteroids, with an onset of action of 4-6 hours, have no immediate effect on anaphylaxis.

CONCLUSION

To prevent near-fatal and fatal reactions from anaphylaxis, the patient, the family, and the physician must remember to follow the necessary steps when treating anaphylaxis. In anaphylaxis, there is no absolute contraindication for epinephrine.

European Survey on Adverse Systemic Reactions in Allergen Immunotherapy (EASSI): a real-life clinical assessment

BACKGROUND

Outside clinical trials, data on systemic reactions (SRs) due to allergen immunotherapy (AIT) are scarce.

METHODS

A prospective, longitudinal, web-based survey of 'real-life' respiratory allergen immunotherapy (AIT) clinical practice was conducted in France, Germany and Spain. SRs were recorded and coded according to the Medical Dictionary for Regulatory Activities (MedDRA) and risk factors associated with SRs were identified.

RESULTS

A total of 4316 patients (corresponding to 4363 ongoing courses of AIT) were included. A total of 109 SRs were recorded, and 90 patients (2.1%) presented at least one SR. Most of the SRs occurred in subcutaneous allergen immunotherapy (SCIT) (89%, n = 97). The most frequently reported symptoms were urticaria, rhinitis, dyspnoea and cough. Respiratory symptoms appeared before skin symptoms. Most SRs occurred during the up-dosing phase (75.8%) and were mild in severity (71.6%). Intramuscular adrenaline was administered in 17 SRs, but only 65% of these were subsequently classified as anaphylaxis. Independent risk factors for SRs during SCIT were as follows: the use of natural extracts (odds ratio, OR) [95% confidence interval (CI)] = 2.74 [1.61-4.87], P = 0.001), the absence of symptomatic allergy medications (1.707 [1.008-2.892], P = 0.047), asthma diagnosis (1.74 [1.05-2.88], P = 0.03), sensitization to animal dander (1.93 [1.21-3.09], P = 0.006) or pollen (1.16 [1.03-1.30], P = 0.012) and cluster regimens (vs rush) (4.18 [1.21-14.37], P = 0.023). A previous episode of anaphylaxis increased the risk for anaphylaxis in SCIT (OR [95% CI] = 17.35 [1.91-157.28], P = 0.01).

CONCLUSION

AIT for respiratory allergy is safe, with a low number of SRs observed in real-life clinical practice. A personalized analysis of risk factors could be used to minimize SRs.

Safety and efficacy of rush allergen-specific immunotherapy in Chinese allergic rhinitis patients

The purpose of this prospective, open-IV clinical trial was to assess the safety and efficacy differences between Rush immunotherapy (RIT) and conventional immunotherapy in Chinese allergic rhinitis (AR) patients. The trial involved 174 patients with AR. They were divided into two groups according to their preference of therapy: RIT or conventional immunotherapy. A total of 162 patients completed a 1-year treatment course. For safety and effectiveness evaluation, the local and systemic adverse reactions were recorded throughout the initial phase of both groups. Weeks 0, 2, 5, and 17 were set as observation time points for immunoglobulin G (IgG) and IgG4. Besides that, another observation time point (Week 11) was added in for a visual analog scale (VAS) and a weekly drug dosage scale. In the RIT group, systemic adverse events of AR were similar to those of the conventional therapy group. LTB4 was descended. The VAS of the RIT group did not show a downward trend clearly, instead Week 5 was higher compared with Week 0. The weekly drug dosage scale did not indicate a significant decline, but there was a clear rise in IgG4 in the RIT group. The safety and efficacy of RIT for AR is positive, but further study is needed for improvement.

Exploratory study of tolerability and immunological effect of a short up-dosing immunotherapy phase with a standardised allergen extract derived from pollen of Olea europaea

BACKGROUND

A new subcutaneous specific immunotherapy (SCIT) product adsorbed on aluminium hydroxide has been developed with a short and simplified up-dosing phase, containing a biologically standardized allergen pollen extract from Olea europaea.

OBJECTIVE

To assess the tolerability profile of the updosing phase and its immunological effect, in terms of specific IgG4 and IgE levels and immediate skin reactivity.

MATERIAL AND METHODS

The study was an exploratory, multi-centre, open-label, single-arm, phase II/III clinical trial. Adults with a clinical history of allergic rhinoconjunctivitis with/without asthma due to sensitization to olive pollen were selected. Five up-dosing doses (300, 600, 3000, 6000 and 15000SQ+) were administered at weekly intervals, followed by a maintenance dose (15000SQ+) after 2 weeks. Adverse events were collected during the 30 min observation period after injections, after a telephone contact 2 days after each visit, and after reviewing the subjects' diary. IgG4 and IgE levels and immediate skin reactivity were evaluated at the beginning and at the end of the trial.

RESULTS

Ninety-three subjects were included in the trial (mean age, 35.7 ± 10.3 years; women, 66.7 %). A total of 95 adverse drug reactions, all mild in intensity and non-serious, were reported during the trial: 85 local in 34.4 % subjects, 9 systemic in 4.3 % subjects and one non-specific (grade 0). Within 6 weeks, significant changes in IgG4 and IgE levels and in immediate skin reactivity to Olea europaea were accomplished.

CONCLUSION

This new SCIT derived from pollen of Olea europaea presented a good tolerability profile and induced significant immunological responses already after a 6 week treatment. However, the non-controlled design may limit the interpretation of these results.

TRIAL REGISTRATION

EudraCT no: 2011-004852-20; ClinicalTrials.gov Identifier: NCT01674595.

Incidence and risk factors for subcutaneous immunotherapy anaphylaxis: the optimization of safety

Fatal reactions related to subcutaneous allergen immunotherapy are rare: one event in 2.5 million injections has been reported in the USA and none in Europe. The prevalence of very severe systemic reactions (systemic adverse events [SAEs]) is one in 1 million injections. Though the serious events rate is decreasing and the majority of SAEs (∼0.2% per injection) are moderate and reversible, they still represent a major concern. Uncontrolled asthma, long-term therapy with β-blockers and high degree of allergen sensitivity are generally considered risk factors. The relevance of other conditions, like previous local reactions, the use of extracts conjugated with adjuvants and accelerated build-up schedules is controversial, as well as the role of preventative strategies. A careful risk assessment of patients and optimal administration procedures may significantly decrease the risk of SAEs. However, more uniform safety data are required and an accurate safety profile should be provided for every allergen product.

A high polymerized grass pollen extract is efficacious and safe in a randomized double-blind, placebo-controlled study using a novel up-dosing cluster-protocol

BACKGROUND

Cluster immunotherapy represents an interesting alternative to conventional up-dosing schedules because it allows achieving the maintenance dose within a shorter time interval. In this study, the efficacy and safety of cluster immunotherapy with a high polymerized allergen extract of a grass/rye pollen mixture have been evaluated in a randomized, double-blind, placebo-controlled, multicenter study.

METHODS

In total, 121 patients with allergic rhinoconjunctivitis due to grass pollen were randomized 1 : 1 to verum or placebo group. A short cluster up-dosing schedule of only 1 week was applied to achieve the maintenance dose which was administered monthly during the study period of 1 year. Total combined symptom and medication score (TCS) was defined as primary outcome parameter. Secondary outcome parameters were individual symptom and medication scores, 'well days,' global improvement as well as immunological effects and nasal allergen challenge. The safety profile was evaluated based on the European academy of allergy and clinical immunology grading system.

RESULTS

Significant reduction in the verum compared to the placebo group (intention-to-treat, population, verum: n = 55; placebo: n = 47) was found regarding TCS (P = 0.005), rhinoconjunctivitis total symptom score (RTSS, P = 0.006), and total rescue medication score (TRMS, P = 0.002). Additionally, secondary outcomes such as 'well days,' nasal challenge results, and increase of specific IgG4 were in favor of the active treatment. All systemic adverse reactions (0.8% of all injections in the verum group) were of mild intensity. No severe reactions related to the study medication were observed.

CONCLUSION

Cluster immunotherapy with high polymerized grass pollen extracts resulted in significant clinical efficacy and has been shown to be a safe treatment for grass pollen-allergic patients.

Is faster safer? Cluster versus short conventional subcutaneous allergen immunotherapy

AIM

Few studies have compared cluster immunotherapy and conventional administration regimens. The aim of this study was to establish the safety profile of these different regimens in patients with allergic respiratory diseases who received index-of-reactivity (IR)-standardized allergen extracts by the subcutaneous route.

MATERIALS & METHODS

The safety of subcutaneous immunotherapy (SCIT), administered by means of a 4-week cluster titration schedule (cluster-SCIT) or by an 8-week short conventional titration schedule (SC-SCIT), both with a target dose of 8 IR, was assessed in a retrospective, observational, multicenter study.

RESULTS

A total of 658 patients (339 cluster-SCIT and 319 SC-SCIT) were recruited from 92 sites in Spain. Injection site reactions occurred in 25.1 and 27.3% of patients treated with cluster-SCIT and SC-SCIT, respectively. Systemic reactions (European Academy of Allergy and Clinical Immunology criteria) were reported for 0.2% of doses and 1.5% of patients with cluster-SCIT, and 0.7% of doses and 4.4% of patients with SC-SCIT. Most reactions were mild and there were no grade 3 or 4 systemic reactions. No life-threatening systemic reactions, anaphylactic shock, or adverse events leading to therapy discontinuation were reported.

CONCLUSION

The safety profile of the cluster regimen supports the use of accelerated SCIT schedules with IR-standardized allergen extracts compared with short conventional schedules, particularly if similar extracts and application methods are used.

Safety of immunotherapy in patients with rhinitis, asthma or atopic dermatitis using an ultra-rush buildup. A retrospective study

BACKGROUND

Allergen-specific immunotherapy is a proven, highly effective treatment for IgE-mediated diseases. However, ultra-rush immunotherapy is prescribed infrequently because of the perception that accelerated immunotherapy buildup leads to a higher rate of systemic reactions.

OBJECTIVE

To evaluate the frequency of adverse reactions in patients with IgE-mediated diseases receiving house dust mite (HDM) ultra-rush immunotherapy.

METHODS

A retrospective, observational study was conducted for patients with IgE-mediated diseases receiving allergen-specific immunotherapy. Subcutaneous immunotherapy with depigmented polymerized mites extract was administered in two refracted doses of 0.2 and 0.3 ml at first injection, and in single 0.5 ml doses in subsequent monthly injections. A 30 min observation time was required after each injection. Systemic reactions were graded using the World Allergy Organisation grading system.

RESULTS

575 patients were included. The age range was 1-83 years. Most patients had respiratory diseases (544) and 101 patients had atopic dermatitis. A total of 27 patients (4.6%) experienced 139 reactions (reactions/injections: 1.9%); 22 patients (3.8%) experienced 134 local reactions (local reactions/injections: 1.8%). Eight patients (1.3%) experienced eight systemic reactions (systemic reactions/injections: 0.1%). Five systemic reactions were grade 2 and three grade 1. Two systemic reactions were reported during buildup. There were no fatalities.

CONCLUSION

Taking into account the possible bias for the retrospective design of this study we observed that immunotherapy for patients with IgE-mediated diseases using a depigmented polymerized mites extract, with an ultra-rush buildup, has similar frequency of systemic reactions than that seen in slower buildup immunotherapy in other studies. Accelerated buildup could improve patients' adherence and reduce dropout rates.

Trends in Specific Immunotherapy for Allergic Rhinitis: A Survey of Chinese ENT Specialists

Purpose

Specific immunotherapy (SIT) is a suitable but uncommon treatment option for allergic rhinitis (AR) in China. The current understanding and attitude of Chinese ENT (ear, nose, and throat) specialists in regards to SIT is unclear. This study investigates current trends in the awareness and application status of SIT among Chinese ENT specialists.

Methods

We performed a nationwide, cross-sectional survey with a specially designed questionnaire given to 800 ENT specialists in China. A member of the trained research group conducted face-to-face interviews with each respondent.

Results

Most of the respondents considered AR (96.0%) and allergic asthma (96.0%) the most suitable indications for SIT. Of all respondents, 77.0% recommended the application of SIT as early as possible; in addition, SIT was considered 'relatively controllable and safe' by most respondents (80.6%). The highest allergen-positive rate in AR was associated with house dust mite (47.7%) and obvious differences existed among geographical regions. Conventional subcutaneous immunotherapy was the most highly recommended treatment option (96.2%). 'The high cost of SIT' (86.6%) and 'lack of patient knowledge of SIT' (85.2%) were probably the main reasons for the lower clinical use of SIT in China.

Conclusions

Most cases showed that the opinions of Chinese ENT specialists appeared to be in agreement with recent SIT progress and international guidelines; however, many areas still need to enhance the standardization and use of SIT in China. Clinical guidelines for SIT require improvement; in addition, Chinese ENT specialists need continuing medical education on SIT.

Cluster subcutaneous allergen specific immunotherapy for the treatment of allergic rhinitis: a systematic review and meta-analysis

Background

Although allergen specific immunotherapy (SIT) represents the only immune- modifying and curative option available for patients with allergic rhinitis (AR), the optimal schedule for specific subcutaneous immunotherapy (SCIT) is still unknown. The objective of this study is to systematically assess the efficacy and safety of cluster SCIT for patients with AR.

Methods

By searching PubMed, EMBASE and the Cochrane clinical trials database from 1980 through May 10th, 2013, we collected and analyzed the randomized controlled trials (RCTs) of cluster SCIT to assess its efficacy and safety.

Results

Eight trials involving 567 participants were included in this systematic review. Our meta-analysis showed that cluster SCIT have similar effect in reduction of both rhinitis symptoms and the requirement for anti-allergic medication compared with conventional SCIT, but when comparing cluster SCIT with placebo, no statistic significance were found in reduction of symptom scores or medication scores. Some caution is required in this interpretation as there was significant heterogeneity between studies. Data relating to Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) in 3 included studies were analyzed, which consistently point to the efficacy of cluster SCIT in improving quality of life compared to placebo. To assess the safety of cluster SCIT, meta-analysis showed that no differences existed in the incidence of either local adverse reaction or systemic adverse reaction between the cluster group and control group.

Conclusion

Based on the current limited evidence, we still could not conclude affirmatively that cluster SCIT was a safe and efficacious option for the treatment of AR patients. Further large-scale, well-designed RCTs on this topic are still needed.

Accelerated immunotherapy schedules

Rush and cluster immunotherapy schedules are accelerated immunotherapy build-up schedules. A cluster immunotherapy schedule involves the patient receiving several allergen injections (generally 2-4) sequentially in a single day of treatment on nonconsecutive days. The maintenance dose is generally reached in 4-8 weeks. In rush immunotherapy protocols, higher doses are administered at 15- to 60-min intervals over a 1- to 3-day period until the maintenance dose is achieved. This review will serve as an update for accelerated immunotherapy schedules. The review will include recent investigations demonstrating the safety of cluster schedules in atopic dermatitis, pediatric patients, and inhalant allergen mixtures and an accelerated protocol utilizing an infusion pump for allergen delivery. There has also been further elucidation on the immunological changes which occur during accelerated immunotherapy. Finally, new studies analyzing systemic reaction risk factors are discussed.

Chapter 17: Immunomodulation of allergic sinonasal disease

IgE hypersensitivity is important to the pathogenesis of allergic diseases and the development and persistence of airway inflammation. Allergic immunomodulation encompasses various therapies that attempt to suppress or modify the immune mechanisms responsible for IgE-mediated disease. These include allergy immunotherapy (AIT) in the forms of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT), as well as the emergence of biological agents, such as anti-IgE, for allergic respiratory disease. Clinical evidence strongly supports the efficacy and safety of AIT for the treatment of allergic rhinitis, allergic conjunctivitis, and allergic asthma, but for chronic rhinosinusitis evidence is lacking. In allergic rhinitis, the decision to initiate AIT depends on the degree to which symptoms can be reduced by avoidance and medication, the amount and type of medication required to control symptoms, the adverse effects of medication, the severity and duration of symptoms, and their effect on quality of life. AIT has the potential to produce sustained long-lasting immune modulation and possibly avoid or reduce lifelong requirements for medical therapy. Although SLIT is currently being evaluated, SCIT remains the preferred form of AIT in the United States because of robust efficacy data, availability of allergen extracts, and current Food and Drug Administration approval. However, SLIT holds the potential for greater patient safety and convenience. Other immunomodulators such as anti-IgE also hold promise, but require further investigation.

Immunologic effect and tolerability of intra-seasonal subcutaneous immunotherapy with an 8-day up-dosing schedule to 10,000 standardized quality-units: a double-blind, randomized, placebo-controlled trial

BACKGROUND

International guidelines recommend that allergen-specific immunotherapy for pollen-induced rhinoconjunctivitis is initiated preseasonally. However, because subjects often present to physicians with allergy symptoms during the pollen season, "within-season" initiation of specific immunotherapy is of special interest.

OBJECTIVE

We evaluated the immunomodulatory effects and tolerability of subcutaneous immunotherapy (SCIT) with Standardized Quality (SQ) 6-grass mix and rye allergen extract, using an 8-day intra-seasonal up-dosing schedule to 10,000 SQ-units (SQ-U).

METHODS

In a 9-week, multicenter, randomized, double-blind, placebo-controlled trial, adults (mean age, 34.6 years; 99.3% whites) with grass pollen-induced rhinoconjunctivitis (mean disease duration, 15.1 years) were randomized 3:1 to receive SCIT or placebo. Treatment was initiated during the 2008 pollen season, with an 8-day up-dosing from 100 to 10,000 SQ-U (6 daily injections) followed by 2 maintenance injections of 10,000 SQ-U at intervals of 2 and 4 weeks, respectively. The primary end point examined immunologic effects, assessing the difference in IgE-blocking factor (serum components competing with IgE for allergen binding) between SCIT and placebo at week 9. Secondary/explorative end points included the difference in IgE-blocking factor, specific IgG(4), and specific IgE at various times. Tolerability (adverse events, local and systemic allergic reactions) of the up-dosing schedule was also evaluated.

RESULTS

Of the 148 treated subjects 144 (SCIT n = 109; placebo n = 35) were analyzed for the primary parameter. Immunologic response (significantly higher increase in IgE-blocking factor and IgG(4) levels) occurred with SCIT versus placebo at week 9 (IgE-blocking factor, P = 0.0017; IgG(4,)P = 0.0215). Significant differences were observed as early as week 3. AEs were reported in 60.7% of SCIT- and 30.6% of placebo-treated subjects, with no treatment-related serious AEs. Local allergic reactions occurred in 46.4% of SCIT and 8.3% of placebo subjects (χ(2) test, P < 0.0001). No significant difference was observed between groups in the incidence of systemic reactions (7.1% SCIT vs 5.6% placebo; χ(2) test, P = 0.7413).

CONCLUSIONS

This trial provides the first description of short (8-day) intra-seasonal up-dosing with SCIT, which induced immunologic effects after only 3 weeks, and was generally well tolerated, although it induced a marked increase in the rate of local reactions compared with placebo. ClinicalTrials.gov identifier NCT00807547; ALK trial ID SHX0562.

Factors affecting time required to reach maintenance dose during subcutaneous immunotherapy

BACKGROUND

Subcutaneous immunotherapy (SCIT) demands a significant time commitment on the part of the patient, especially during the escalation period when weekly visits are required. Many patients refuse or discontinue treatment in spite of the demonstrated clinical efficacy of SCIT. Understanding the factors that affect the length of the escalation phase would allow for counseling of patients, which may improve patient compliance. The aims of this study were to determine the mean time required to reach maintenance dose during conventional protocol SCIT and to identify factors that significantly affect the time required to reach maintenance dose.

METHODS

We conducted a retrospective chart review of 55 patients (total of 79 treatment vials) who began SCIT between January 2007 and December 2010 and reached maintenance dose. The effect of demographic data, medical and social history, and SCIT allergen data on the time required to reach maintenance dose were examined using bivariate and multivariate analyses.

RESULTS

The mean time to maintenance dose for the 79 treatment vials was 240.2 days (range, 76-720 days). Males (mean 294.7 days) took significantly longer than females (mean 205.1 days) to reach maintenance dose (p = 0.007). Asthmatics (mean 285.5 days) took significantly longer than nonasthmatics (mean 218.0 days) to reach maintenance dose (p = 0.008). Age also significantly affected the length of the escalation phase; each additional year of age was associated with an increase in 3.9 days needed to reach maintenance dose (p = 0.002).

CONCLUSION

Gender, asthma, and age significantly impact the time required to reach maintenance dose during SCIT.

Early gene expression changes with rush immunotherapy

BACKGROUND

To examine whether whole genome expression profiling could reveal changes in mRNA expression of peripheral blood mononuclear cells (PBMC) from allergic patients undergoing rush immunotherapy (RIT) that might be manifest within the first few months of treatment.

METHODS

For this study, PBMC from three allergic patients undergoing RIT were assessed at four timepoints: prior to RIT, at 1 week and 7 week post-RIT, during build-up and at 4 months, after establishment of a maintenance dose. PBMC mRNA gene expression changes over time were determined by oligonucleotide microarrays using the Illumina Human-6 BeadChip Platform, which simultaneously interrogates expression profiles of > 47,000 transcripts. Differentially expressed genes were identified using well-established statistical analysis for microarrays. In addition, we analyzed peripheral blood basophil high-affinity IgE receptor (Fc epsilon RI) expression and T-regulatory cell frequency as detected by expression of CD3+CD4+CD25bright cells at each timepoint using flow cytometry.

RESULTS

In comparing the initial 2 timepoints with the final 2 timepoints and analyzing for genes with ≥1.5-fold expression change (p less than or equal to 0.05, BH-FDR), we identified 507 transcripts. At a 2-fold change (p less than or equal to 0.05, BH-FDR), we found 44 transcripts. Of these, 28 were up-regulated and 16 were down-regulated genes. From these datasets, we have identified changes in immunologically relevant genes from both the innate and adaptive response with upregulation of expressed genes for molecules including IL-1β, IL-8, CD40L, BTK and BCL6. At the 4 month timepoint, we noted a downward trend in Fc epsilon RI expression in each of the three patients and increased allergen-specific IgG4 levels. No change was seen in the frequency of peripheral T-regulatory cells expressed over the four timepoints.

CONCLUSIONS

We observed significant changes in gene expression early in peripheral blood samples from allergic patients undergoing RIT. Moreover, serum levels for allergen specific IgG4 also increased over the course of treatment. These studies suggest that RIT induces rapid and dynamic alterations in both innate and adaptive immunity which can be observed in the periphery of allergic patients. These alterations could be directly related to the therapeutic shift in the allergen-specific class of immunoglobulin.

Rapid desensitization with autologous sweat in cholinergic urticaria

BACKGROUND

The majority of patients with cholinergic urticaria presents with strong hypersensitivity to autologous sweat. Patients with severe cholinergic urticaria are frequently resistant to H(1) antagonists which are used in conventional therapies for various types of urticaria. It has been reported that desensitization using partially purified sweat antigen was effective in a patient with cholinergic urticaria.

METHODS

The aim of this study is to determine the usefulness of rapid desensitization with autologous sweat in severe cholinergic urticaria, because rapid desensitization has proven to be a quick and effective immunotherapy for allergies to various allergens. Six patients with severe cholinergic urticaria who are resistant to H(1) antagonists and have sweat hypersensitivity were enrolled in a rapid desensitization protocol.

RESULTS

In all six patients, the responses for skin tests with autologous sweat were attenuated after rapid desensitization with autologous sweat. Two of the three cholinergic urticaria patients showed reduced histamine release with autologous sweat after the rapid desensitization with autologous sweat. Further, the rapid desensitization and subsequent maintenance treatment reduced the symptoms in five of the six patients.

CONCLUSIONS

This study provides evidence that rapid desensitization with autologous sweat is beneficial for treating cholinergic urticaria patients resistant to conventional therapy who have sweat hypersensitivity.

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

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

New approaches to managing asthma: a US perspective

Despite remarkable advances in diagnosis and long-term management, asthma remains a serious public health concern. Newly updated expert guidelines emphasize the intra- and inter-individual variability of asthma and highlight the importance of periodic assessment of asthma control. These guidelines update recommendations for step-wise asthma treatment, address the burgeoning field of asthma diagnostics, and stress the importance of a patient and health care professional partnership, including written action plans and self monitoring. The field of asthma therapeutics is expanding rapidly, with promising new treatment options available or in development that may address some of the existing barriers to successful asthma management. These approaches simplify treatment, use combinations of agents in one delivery device that have complementary actions, or target specific pathways involved in asthma patho-physiology. Considerable activity is taking place in asthma pharmacogenetics. This review provides an overview of these new approaches to managing asthma, including their present status and future potential.

[Cluster immunotherapy of persistent allergic rhinoconjunctivitis. Safety aspects of induction therapy with mite depot allergen preparations]

BACKGROUND

Apart from allergen avoidance and pharmacotreatment, specific immunotherapy (SIT) is the most important therapeutic option offered to allergic patients. Clinical efficacy of SIT depends on the specific allergen extract used, the quality and total cumulative amount of allergen applied and the treatment schedule of the therapy. In cluster SIT, 2-3 injections per treatment day are applied resulting in an accelerated achievement of the maintenance dose.

PATIENTS AND METHODS

In this study 79 mite-sensitized adult allergic patients aged 18 to 59 years (mean 27.4+/-7.2 years) were investigated in terms of side-effects of cluster SIT during induction treatment.

RESULTS

A total of 129 local hypersensitivity reactions (>grade 1) occurred or 10.2% of all injections (69% grade 1, 20% grade 2, 11% grade 3 and no grade 4 reactions). The total number of systemic reactions was 40 or 3.2% of all injections with 92% grade 1 and 8% grade 2 reactions. Grade 3 or 4 reactions did not occur.

CONCLUSION

Cluster SIT with depot allergens represents an interesting alternative option to conventional dosage schedules of SIT.

Type 2 immune-inducing helminth vaccination maintains protective efficacy in the setting of repeated parasite exposures

Animal studies have demonstrated that helminth vaccines which induce type 2 immune responses can be protective. To date, however, such vaccines have not been tested against repeated parasite challenges. Since repeated antigenic challenge of patients with allergic disease results in immunologic tolerance, we hypothesized that a helminth vaccine which induces type 2 immune responses may lose its protective efficacy in the setting of repeated parasite exposures (RPEs). To test this hypothesis, we examined whether RPEs induce immunological tolerance and reduce the effectiveness of a type 2 immune-inducing vaccine. BALB/c mice vaccinated against Litomosoides sigmodontis, a filarial nematode of rodents, were repeatedly exposed to irradiated larvae for 2 or 8 weeks or to non-irradiated infectious larvae for three months. Vaccination-induced parasite-specific IgE levels, parasite antigen-driven basophil interleukin 4 (IL-4) release, and Th2 skewing of the cellular immune response remained stable in the face of RPEs. Furthermore, RPEs in vaccinated mice did not augment immunoregulatory responses, as parasite antigen-driven cellular proliferation, production of IL-10, and frequencies of CD4(+)CD25(+)FoxP3(+) regulatory T-cells were not altered by RPEs. Challenge infections with infectious L3-stage larvae resulted in lower worm burdens in vaccinated mice given RPEs than in vaccinated controls. These results demonstrate that vaccines which induce type 2 immune responses can maintain their efficacy in the setting of repeated parasite exposures.

A review of allergen-specific immunotherapy in human and veterinary medicine

This article reviews allergen-specific immunotherapy in human and veterinary medicine. Current hypotheses of possible mechanisms of actions are outlined. Indications, success rates, adverse effects and factors influencing outcome of therapy are discussed in humans, dogs, cats and horses.