Effectiveness and safety of a glutaraldehyde-modified, L-tyrosine-adsorbed and monophosphoryl lipid A-Adjuvanted allergen immunotherapy in patients with allergic asthma sensitized to olive pollen: A retrospective, controlled real-world study

Background

Allergy to olive pollen is one of the primary causes of allergic asthma in Spain. Even though allergen immunotherapy (AIT) has shown clinical benefits in patients sensitized to different allergens, studies in asthmatic patients sensitized to olive pollen are insufficient.

Objective

To assess the effectiveness and safety of an ultra-short course of AIT with an L-tyrosine-adsorbed and monophosphoryl lipid A-adjuvanted olive pollen and olive/grass pollen extract (Pollinex Quattro®) in patients with allergic asthma in the real-world setting.

Methods

Retrospective, controlled study including patients with asthma, with and without allergic rhinitis, caused by sensitization to olive pollen from 11 centers in Spain. Patients received out-of-season (October–March) treatment with AIT in addition to their pharmacological treatment (active group) or pharmacological treatment (control group). Effectiveness variables, including unscheduled visits to the healthcare center, emergency room admissions, symptoms of asthma and rhinitis (following GEMA and ARIA classifications, respectively), and use of medication to treat asthma and rhinitis during the subsequent pollen season were compared between treatment groups.

Results

Of 131 study patients, 42 were treated with their usual asthma medication (control group) and 89 were treated with AIT (active group), either Pollinex Quattro® 100% olive pollen (n = 43, 48.3%) or 50% olive pollen/50% grass pollen (n = 46, 51.7%). Patients’ demographic and clinical characteristics were similar between groups. The mean (SD) number of unscheduled visits to a healthcare center and emergency room admissions due to allergy symptoms was 2.19 (1.40) and 0.43 (0.63) in the control group, and 1.09 (1.25) and 0.11 (0.51) in the active group (P = 0.001 and P = 0.006, respectively). Severity and control of asthma symptoms remained unchanged (P = 0.347 and P = 0.179, respectively), rhinitis type improved (P = 0.025), and severity remained unchanged in the active compared to the control group. The use of short-acting beta-agonists and inhaled corticosteroids to treat asthma symptoms decreased in the active vs. the control group (P = 0.001 and P = 0.031, respectively). Twelve (13.5%) and two (2.2%) patients in the active group experienced local adverse reactions (edema, swelling, erythema, hives, pruritus, and heat), and systemic adverse reactions (hypertensive crisis and low-grade fever) to AIT, respectively; none was serious.

Conclusion

AIT with Pollinex Quattro® specific for olive pollen and olive/grass pollens resulted in reduced visits to the healthcare center and emergency room and the use of asthma medication during the pollen season, indicating that this treatment was safe and effective in treating asthma in patients sensitized to these pollens.