Safety of immunotherapy with Alternaria alternata glutaraldehyde-polymerized allergen extract in adults and children.

Background: Allergies to fungi, such as Alternaria alternata, are significant contributors to respiratory conditions like asthma and rhinitis. Immunotherapy with native A. alternata extracts often results in high rates of adverse reactions. This study evaluates the safety of immunotherapy using glutaraldehyde-polymerized A. alternata extracts in both pediatric and adult populations.

Methods: This observational real-world study involved 738 patients (435 children and 303 adults) monosensitized to A. alternata or polysensitized together to other allergens. Patients received personalized immunotherapy containing polymerized A. alternata extract, either alone or in combination with other polymerized allergens. The concentration of each polymerized allergen in the therapeutic vaccine was 10,000 TU/mL. Side reactions were classified and recorded based on immediate and delayed onset, and their severity was graded according to the EAACI guidelines.

Results: All side reactions were expected and related to the intrinsic properties of allergens. The number of injections administered was 7392, with 4137 to children and 3255 to adults. Thirteen relevant local reactions (0.24% in children, 0.09% in adults) and seven systemic reactions (0.09% overall) were observed. Systemic reactions included mild to moderate symptoms, such as mild bronchospasm and rhinitis. Severe reactions were not reported.

Conclusion: Immunotherapy with glutaraldehyde-polymerized A. alternata, alone or in combination with other polymerized allergens, is safe and well-tolerated in both children and adults. The polymerized extracts allow for higher concentrations and faster administration schedules, providing an effective treatment option for patients with fungal allergies, including those polysensitized to multiple allergens.