Predominant Sensitizations to Single Bee Venom Allergens as a Risk Factor for Therapy Failure

Study Overview
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Brief Summary
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Venom immunotherapy (VIT) is an established treatment for Hymenoptera venom allergy and provides long-term protection from further generalized reactions in almost all patients. However, it is still unclear why bee VIT is less effective than vespid VIT. The preliminary data show that not only predominant Api m 10 sensitization but also other predominant sensitizations may be relevant as risk factors for treatment failure. Interestingly, all patients with a predominant Api m 10 sensitization who received bee VIT with a venom preparation with a supposed lack of Api m 10 tolerated sting challenges. Therefore, a multicenter study with a sufficient number of patients with treatment failure is urgently required, to clarify if predominant sensitization to a bee venom allergen is a risk factor for treatment failure. If predominant sensitization is a risk factor and caused by underrepresented components in bee venom preparations used for VIT, bee venom preparations may be optimized in the future and patients would benefit from a more effective VIT.

Official Title
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Predominant Sensitizations to Single Bee Venom Allergens as a Risk Factor for Therapy Failure

Conditions
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Bee Venom Allergy

Intervention / Treatment
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* Drug: Insect Venom


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Legally competent male and female subjects aged from 18 to 70 years with a history of a systemic anaphylactic sting reaction (≥ grade I according to the classification of Ring and Messmer) after bee stings, who will receive bee venom immunotherapy Exclusion Criteria: Contraindications to VIT

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| patients who will be treated with bee venom immunotherapy<br> | Drug: Insect Venom<br>* Patients will be treated with bee venom immunotherapy (protocol can be selected by patient). Blood samples are taken before starting VIT to determine specific immunoglobulin E (sIgE) Levels for bee venom components. Patients are sting challenged and the outcome will be recorded.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The primary objective of the study is to evaluate whether predominant sensitization to Api m 10 is a risk factor for treatment failure. | A sensitization is considered predominant if the proportion of specific IgE to a single venom allergen is at least 65% of the specific IgE to the venom preparations. | depends on the protocol used for VIT and the date of the sting challenge, a maximum of about 6 months if sting challenge is performed right after reaching the maintenance dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To evaluate if predominant sensitization to either Api m 1, Api m 2, Api m 3 or Api m 5 is a risk factor for treatment failure. |  | depends on the protocol used for VIT and the date of the sting challenge, a maximum of about 6 months if sting challenge is performed right after reaching the maintenance dose | 
| To evaluate if low immunoglobulin G4 (IgG4) levels to bee venom or to Api m 1, Api m 2, Api m 3, Api m 5, or Api m 10 after VIT is a risk factor for treatment failure. |  | depends on the protocol used for VIT and the date of the sting challenge, a maximum of about 6 months if sting challenge is performed right after reaching the maintenance dose | 
| To evaluate if systemic side effects are a risk factor for treatment failure. |  | depends on the protocol used for VIT and the date of the sting challenge, a maximum of about 6 months if sting challenge is performed right after reaching the maintenance dose | 
| To evaluate if antihypertensive medication is a risk factor for treatment failure. |  | depends on the protocol used for VIT and the date of the sting challenge, a maximum of about 6 months if sting challenge is performed right after reaching the maintenance dose |