Pre-season birch allergy shots significantly reduce symptoms, study finds

Getting ahead of allergy season might be the key to surviving it. A phase 3 randomized trial found that patients with birch pollen allergies who received a short preseasonal course of the investigational allergoid EP-088_T502 — delivered via eight subcutaneous injections over six visits — experienced significantly fewer symptoms and needed less allergy medication during peak pollen season compared to those given a placebo.

The treatment also showed meaningful immune benefits, with protective IgG4 antibody levels rising sixfold in treated patients. Adults reported quality-of-life scores that were 20% better during peak season and 18% better before the season compared to placebo. The most common side effect was injection site itching, and systemic allergic reactions occurred in about 6% of treated patients.

By the Numbers:

• Mean absolute difference in combined symptom and medication scores: -0.31 (P = .0169)
• IgG4 levels rose sixfold (0.50 mg/L → 3.01 mg/L) in treated patients
• IgE-to-IgG4 ratio fell 73% from baseline with treatment
• Quality-of-life scores were 20% better during peak season vs. placebo

Why it matters: For the millions who suffer through birch pollen season each year, a short pre-season injection course could offer real relief — without the burden of year-round allergy shots.