Efficacy and safety of specific immunotherapy with a modified mite extract

Ultrarush schedule of subcutaneous immunotherapy with modified allergen extracts is safe in paediatric age

Background

Traditional subcutaneous immunotherapy up dosing with allergenic extracts has been shown to be associated with frequent adverse reactions. In recent studies it has been demonstrated that using modified extracts, namely allergoids, it is a safe and effective procedure particularly on accelerated schedules. However data assessing its safety in paediatric age is scarce.

Objective

To evaluate the safety profile in paediatric population of using modified allergen extracts, in an ultrarush schedule, to reach the maintenance dose in the first day.

Methods

We included children undergoing treatment with subcutaneous immunotherapy during a five-year period, using modified aeroallergen extracts, depigmented, polymerized with glutaraldehyde and adsorbed on aluminium hydroxide using an ultrarush induction phase. The type of adverse reactions during the ultrarush protocol was recorded.

Results

We studied 100 paediatric patients (57 males) with a mean age of 11.6 years (5 to 18 years; standard deviation, 3.3), all with moderate to severe persistent rhinitis, with or without allergic conjunctivitis, asthma and atopic eczema, sensitized to mites and/or pollens. All reached the maintenance dose of 0.5 mL in the first day, except 1 child. During the ultrarush protocol the total number of injections was 199. There were 21 local adverse reactions in 11 patients, 11 immediate and 10 delayed; from those, had clinical relevance 1 immediate and 4 delayed. Systemic reactions were recorded in 2 cases, both immediate and mild.

Conclusion

The ultrarush protocol, without premedication, was a safe alternative to be used in paediatric age during the induction phase of subcutaneous immunotherapy using allergoid depigmented extracts.

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.

Safety of specific immunotherapy using a depigmented and polymerised extract of Dermatophagoides pteronyssinus in children under five years of age

BACKGROUND

Different opinion documents point to a patient age of under five years as a relative contraindication to specific immunotherapy, arguing that this age group has a greater risk of developing anaphylaxis, and that specially trained personnel are needed to deal with the problem if it occurs. However, insufficient evidence exists to support such an affirmation.

PATIENTS AND METHODS

A retrospective follow-up observational study was made of patients aged 60 months or younger who had been subjected to specific immunotherapy. We included 77 children with a diagnosis of extrinsic bronchial asthma (n=68), extrinsic spasmodic cough (n=5) and allergic rhinitis (n=4) confirmed by clinical criteria and prick-test, with specific IgE positivity to Dermatophagoides pteronyssinus. All patients received specific immunotherapy with an extract of depigmented D. pteronyssinus polymerised with glutaraldehyde, involving an initial cluster protocol of two weeks and monthly maintenance doses. All observed adverse reactions were recorded, and classified according to European Academy of Allergy and Clinical Immunology (EAACI) criteria.

RESULTS

A total of 1837 doses were administered to the 77 patients, with four adverse reactions being observed in three patients. Three reactions (0.16% of the administered doses) were local and immediate, while one was systemic and of grade 2 (0.05% of the administered doses) - consisting of an episode of nocturnal wheezing.

CONCLUSIONS

Specific immunotherapy in children under five years of age with the extract used is safe. We consider that further studies are needed, involving other types of extracts, to allow reconsideration of the relative contraindication of patient age for the administration of immunotherapy.

Efficacy, safety, and immunological effects of a 2-year immunotherapy with Depigoid birch pollen extract: a randomized, double-blind, placebo-controlled study

BACKGROUND

Rhinoconjunctivitis due to birch pollen sensitization is common in Northern Europe. A depigmented polymerized birch pollen extract - Depigoid has been developed for immunotherapy.

OBJECTIVE

To evaluate its clinical efficacy, safety, and effects on immunological parameters.

METHODS

Sixty-one patients aged 7-69 years were included in a randomized, double-blind, placebo-controlled trial of subcutaneous immunotherapy (SCIT) using depigmented polymerized birch pollen extract. SCIT consisted of four increasing doses at 7-day intervals, followed by maintenance injections of 500 DPP (corresponding to 30 microg Bet v1 before depigmentation) at 6-week intervals for 18 months. The primary outcome was the combined symptom and medication score during the 2006 birch pollen season. The frequency of peripheral blood mononuclear cells (PBMC)producing IL-4, IL-10, IL-12, and IL-13 was assessed in a subgroup of patients by ELISPOT assay.

RESULTS

After 18 months of treatment, the median combined symptom and medication score (upper/lower quartile) of treated patients was significantly lower than those on placebo: 8.0 (5.8-10.3) and 12.6 (8.6-16.2), respectively (P=0.004). Systemic reactions occurred in 29 patients (12 active, 17 placebo), were grades 1 or 2, and none required specific treatment. After 18 months of treatment, mean serum concentrations of specific IgE increased significantly in both groups (P<0.0001) whereas serum concentrations of both specific IgG1 and IgG4 only increased significantly in the SCIT group (P=0.002) and not in the placebo group. The seasonal increase in numbers of IL-4- and IL-13-producing PBMC was blunted by immunotherapy.

CONCLUSIONS

SCIT with depigmented polymerized birch pollen extract significantly reduced symptom and medication scores when compared with the placebo, was well tolerated, and resulted in immunological changes comparable with those of native pollen extracts.

Safety of a depigmented, polymerized vaccine for the treatment of allergic rhinoconjunctivitis and allergic asthma

BACKGROUND

Clinical efficacy of specific immunotherapy (SIT) with depigmented, polymerized allergen extracts is well documented in placebo-controlled trials, and safety data are encouraging although further data are required.

METHODS

We enrolled 768 patients (51% men; mean age, 31 years) in this prospective multicenter study on safety and clinical effects of Depigoid (Laboratorios LETI, S.L., Madrid, Spain). Immunotherapy consisted of four injections of increasing doses of Depigoid at weekly intervals followed by monthly maintenance injections. All adverse events were documented. Moreover, nose, eye, and lung symptoms were assessed at baseline after 3 and 6 months. Results were compared with the scores of the preceding season.

RESULTS

Rates for local and systemic reactions that might possibly be related to the study medication were 2.36 and 4.56/1000 injections, respectively. With 5923 injections given, 14 local reactions were reported (5 patients), and 27 systemic reactions were reported, including 20 of grade 1 (6 patients) and 7 of grade 2 (4 patients). The best safety profile was seen for patients vaccinated against house-dust mites. Reductions in nose, eye, and lung symptoms as well as in concomitant medication compared with either the preceding season (pollen-sensitized patients) or the baseline (house-dust mite-sensitized patients) were observed at the end of study.

CONCLUSION

In this large multicenter study on 768 patients with allergic rhinoconjunctivitis and allergic asthma under daily practice conditions SIT with Depigoid was well tolerated with low rates of local and systemic reactions. Furthermore, SIT resulted in considerable reductions in symptoms and concomitant medication.

Safety of anti-IgE treatment with omalizumab in children with seasonal allergic rhinitis undergoing specific immunotherapy simultaneously

INTRODUCTION

Seasonal allergic rhinitis (SAR) affects at least 10-25% of the Caucasian race and about 40% of patients are children. Standard treatment of SAR is specific immunotherapy (SIT), but anti-allergic drugs can significantly enhance efficacy of SIT. One candidate is the humanized monoclonal anti-IgE antibody omalizumab.

MATERIAL AND METHODS

Randomized, double-blind, placebo-controlled, multi-centre trial in Germany. A total of 221 children were randomly assigned to four different groups and treated with SIT (either grass or birch pollen), starting at least 14 wk before the local birch pollen season. After the 12-wk SIT titration phase, either anti-IgE (omalizumab) or placebo (NaCl 0.9%) therapy was added. This combination therapy with SIT and anti-IgE or placebo lasted 24 wk. To record local reactions and adverse events (AE), the injection site was examined by a clinician 20 min after application of study medication. Further, patients stated any AE and the use of rescue medication by means of a diary 3 days after every injection. Finally, any AE or serious adverse event (SAE) reported by the patients was specified on a standard form by clinicians. Overall tolerance was judged by the doctors according to the patient's diaries. To test differences between the groups, we used either the two-sided Wilcoxon rank-sum test or the two-sided chi-square test.

RESULTS

Tolerability of SIT and omalizumab treatment was good (82% of patients). Only some AE with possible causal relationship to treatment occurred slightly more often in the verum groups, i.e. local reactions (16.8 vs. 12.3%) and gastrointestinal (2.7 vs. 0.9%) and ear symptoms (1.8 vs. 0%). Most AE (93.4% in omalizumab and 87.2% in placebo group) were judged by the patients as mild to moderate. SAE were restricted to four patients with asthma in the placebo group, two subjects with headache in the verum group and three patients with infections (two in verum and one in placebo group). Only the cases of asthma were judged to be possibly related to study medication. Further, redness and swelling at the SIT injection site appeared significantly more often in the placebo group which suggests a positive effect of omalizumab on local reaction induced by SIT.

CONCLUSION

Omalizumab represents an important clinical advance in the management of allergic diseases and can be considered to be safe in children.

Comparison of the long-term efficacy of subcutaneous and sublingual immunotherapies in perennial rhinitis

BACKGROUND

Both sublingual and subcutaneous immunotherapies have a documented clinical efficacy, but only a few comparative studies have been performed.

OBJECTIVES

To evaluate and compare the long-term efficacies of subcutaneous and sublingual immunotherapy.

METHODS

One hundred and ninety-three patients with house dust mite allergies, out of an original total of 230, were treated with subcutaneous and sublingual house dust mite-specific immunotherapies for 3 years and also observed for 3 years after discontinuation of the treatment. The patients were randomized into 2 groups: the sublingual group (97 patients) and the subcutaneous group (96 patients). The therapy's success was evaluated using the symptom score, skin prick test results, and the nasal allergen challenge score. The patients were evaluated at the beginning of the study, at the end of years 1, 2, and 3, and also at the end of the 1st and 3rd years after discontinuation of the specific immunotherapy treatment.

RESULTS

Immunotherapy induced a significant improvement during the treatment and the follow-up period. We found a greater improvement in the subcutaneous group compared to the sublingual group when we looked at the comparative results of the total 6 years.

CONCLUSION

We suggest subcutaneous immunotherapy for patients with perennial allergic rhinitis due to the better results that were obtained during our study period. Nevertheless, sublingual immunotherapy is now accepted by WHO as a valid alternative to the subcutaneous route and should be used in all patients who require immunotherapy and do not accept the subcutaneous route of allergen administration.

Local and systemic reactions occurring during immunotherapy: an epidemiological evaluation and a prospective safety-monitoring study

The efficacy of specific immunotherapy in allergic patients with IgE-mediated rhino-conjunctivitis, asthma and allergic reaction for stinging insects suggests the opportunity of improving technical procedures to minimize risk and optimise the safety of immunotherapy. This study investigated both local and systemic reactions, occurring in a population of 218 patients undergoing immunotherapy, in an attempt to correlate them with some parameters as well as age, sex and allergenic extracts. The epidemiological evaluation was based on the administration of a questionnaire to 218 patients in order to assess possible reactions to immunotherapy. The following data were evaluated: personal data, diagnosis, specific allergens, adverse reactions undergone during treatment, number of reactions and symptoms. The patients were followed-up by the medical staff of the Section of Allergological and Immunological Disease (SAID), University of Bari (Bari-Italy) for compilation of questionnaires. We found a correlation between female sex and adverse reactions. Among 107 patients referring reactions to the immunotherapy, 71 patients (66.3%) presented only local reactions; 11 patients (10.3%) systemic reactions and 25 patients (23.4%) systemic reactions associated with local reactions. Parietaria was mostly involved in patients with local reactions, instead, in patients with systemic reactions the prevalent allergens seem to be Dermatophagoides and grass-pollen. Rhinitis was the most frequent diagnosis for patients who have presented both local and systemic reactions. In our study, we had frequently mild systemic reactions and some cases of respiratory difficulties, while it is evident that in our group of patients no cases of anaphylaxis occurred. In addition, we considered some events before the administration of immunotherapy, such as assumption of drugs, meals, exposure to sun, stress or physical activity and the percentage of adverse reactions. On the light of a small number of fatality, immunotherapy represents a safer therapy for allergic diseases; nevertheless, our data suggest that safety is strictly correlated with prescriptions by specialists, administration by trained physicians and accurate follow-up of patients. In particular it is recommended to avoid some events before the administration of immunotherapy, above all the assumption of drugs and physical exercise.

Mite immunotherapy

Dermatophagoides pteronyssinus and D. farinae are the most common house dust mites and are among the most common sources of indoor allergens worldwide. These species are very common in humid regions, where most allergic individuals are sensitized to house dust mites. Specific immunotherapy with mite extracts has demonstrated clinical benefits in several double-blind, placebo-controlled trials that are included in recent reviews of subcutaneous immunotherapy, including pediatric and adult patients with rhinoconjunctivitis and or asthma. Most successful studies of mite immunotherapy have used native allergen extracts adsorbed onto aluminum hydroxide, or chemically modified mite-allergen extracts. Several studies have also shown efficacy using sublingual immunotherapy in pediatric and adult patients with asthma and/or rhinitis. Additionally, the efficacy of subcutaneous immunotherapy has been demonstrated in patients with atopic dermatitis, although more double-blind, placebo-controlled studies are needed. Based on several studies, it cannot be concluded that mite immunotherapy is more dangerous or safer than immunotherapy with grasses, epithelia, or animal epithelia. Because the delivery of high doses of allergen carries with it the risk for immunoglobulin E (IgE)-mediated events, several methods have been developed to reduce specific IgE binding to mite-allergen extracts. An important challenge for future mite immunotherapy modalities is the delivery of relatively high doses without a significant risk for severe reactions.