Side-effects of allergen-specific immunotherapy: a prospective multi-centre study.

Area of Science:

• Allergy and Immunology
• Clinical Research
• Pharmacovigilance

Background:

• Allergen-specific immunotherapy (SIT) is a key treatment for allergic diseases.
• Assessing the safety of SIT is crucial for patient management and treatment evaluation.
• A clinical database was established to monitor side effects and identify risk factors.

Purpose of the Study:

• To evaluate the safety profile of allergen-specific immunotherapy (SIT).
• To identify potential risk factors associated with systemic side effects (SSEs) during SIT.
• To establish an early warning system for changes in the frequency and severity of SIT side effects.

Main Methods:

• A multi-center study involving four allergy centers in Copenhagen, Denmark over three years.
• Data collection on patient demographics, allergens used, treatment regimens, and systemic side effects (SSEs) during the build-up phase.
• Inclusion of 1,038 patients and 1,709 allergens, with a total of 23,047 injections recorded.

Main Results:

• Most patients tolerated SIT well, but significant differences in completion rates without side effects were observed between allergens (e.g., wasp 89%, birch 82%, grass 70%).
• A total of 582 SSEs were reported in 341 patients, with the majority being mild (grade 2, 78%).
• Allergen type was a significant predictor of side effects, with grass pollen causing more issues, while patient or center factors were not predictive.

Conclusions:

• Different allergen extracts possess distinct tendencies to cause side effects during SIT.
• Multi-center studies enhance patient evaluation and improve the efficiency of side effect surveillance.
• Implementing an online, national database for real-time registration of SIT injections could further optimize risk factor evaluation and safety monitoring.