TOPLINE

Patients with birch pollen-induced allergic rhinoconjunctivitis who received a short preseasonal injection course of the investigational mannan-conjugated birch pollen allergoid EP-088_T502 had lower combined symptom and medication scores (CSMSs) during the peak birch pollen season than those given placebo. The treatment also increased birch allergen-specific immunoglobulin (Ig) G4 levels and was generally safe and well tolerated.

METHODOLOGY

• Researchers conducted a confirmatory phase 3 randomized trial at multiple sites in Germany (November 2024-June 2025) to assess the effectiveness and safety of a short preseasonal course of a mannan-conjugated birch pollen allergoid EP-088_T502 in patients with birch pollen-induced allergic rhinoconjunctivitis.
• A total of 278 patients (including 13 adolescents) received eight subcutaneous injections of either placebo (n = 92) or the allergoid (n = 186) across six visits ahead of the 2025 birch pollen season. The planned total active dose was 28,000 mannan therapeutic units over 105 days.
• The main efficacy endpoint was CSMS during the peak 2025 birch pollen season, with higher scores reflecting more severe symptoms and greater allergy medication use. Patients logged their symptoms and allergy medication use daily in a smartphone diary app.
• Other endpoints were health-related quality of life and serum levels of IgE, IgG, and IgG4 specific to the birch pollen allergen, Bet v 1, measured before and after treatment. Safety and tolerability were also assessed.

TAKEAWAY

• Among all randomly assigned patients who received at least one dose, treatment significantly reduced the mean daily additive CSMSs compared with placebo (mean absolute difference, -0.31; P = .0169). The effect was consistent among patients who followed the protocol and among those with no missing diary data during the peak pollen season.
• Among adults, health-related quality of life scores were 20% better with treatment than with placebo during peak season and 18% better before the season (P < .05 for both).
• Bet v 1-specific serum IgG4 levels rose sixfold in those receiving treatment (from 0.50 mg/L to 3.01 mg/L) and remained largely unchanged in those given placebo (P < .0001). The ratio of Bet v 1-specific IgE to IgG4 fell 73% from baseline with treatment, while Bet v 1-specific serum IgE level was about twofold higher in those receiving treatment than in those given placebo (P < .0001 for both).
• Injection site itching was the most commonly reported unsolicited treatment-emergent adverse event with active treatment. Systemic allergic reactions occurred in 5.9% of treated patients (11 of 186), including one treatment-related grade 3 reaction.

IN PRACTICE

"The findings were consistent in direction with those of previous EP-088_T502 studies," the authors wrote.

SOURCE

Ralph Mösges, with ClinCompetence Cologne GmbH, Cologne, Germany, was the corresponding author of the study, which was published online on October 4 in Clinical and Translational Allergy.

LIMITATIONS

The adolescent subgroup was small, limiting definitive conclusions to be drawn about the treatment outcomes in this population.

DISCLOSURES

The authors did not report specific funding for the trial. Inmunotek S.L. funded the article processing charges. Several authors were employees or shareholders of Inmunotek or reported receiving grants or personal fees from the company, and several reported having ties to a wide range of other companies.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.