Randomized controlled trial of a ragweed allergy immunotherapy tablet in North American and European adults

J Allergy Clin Immunol. 2013 May;131(5):1342-9.e6. doi: 10.1016/j.jaci.2013.03.019.


Background: In North America and Europe, millions of patients experience symptoms of allergic rhinitis with or without conjunctivitis (AR/C) on exposure to ragweed pollen. The disease burden can be significant, with most patients relying on symptomatic medications without disease-modifying potential. However, novel sublingual immunomodulatory treatment options may potentially play an important role if efficacy and side effect profiles allow the convenience of self-administration.

Objectives: This study evaluated an allergy immunotherapy tablet (AIT; SCH 39641/MK-3641) for treatment of ragweed-induced AR/C in the first large randomized, double-blind multinational trial of this therapeutic modality for ragweed allergy.

Methods: Adults (n = 784) with short ragweed-induced AR/C were randomly assigned to approximately 52 weeks of daily self-administered ragweed AIT of 1.5, 6, or 12 units of Ambrosia artemisiifolia major allergen 1 (Amb a 1-U) or placebo. Subjects could use as-needed allergy rescue medication. Symptoms and medications were recorded daily. The primary efficacy end point was total combined daily symptom/medication score (TCS) during peak ragweed season. Safety was monitored through adverse event diaries maintained through study duration.

Results: During peak ragweed season, ragweed AIT of 1.5, 6, and 12 Amb a 1-U reduced TCS by 9% (-0.76; P = .22), 19% (-1.58; P = .01), and 24% (-2.04; P = .002) compared with placebo. During the entire season, ragweed AIT of 1.5, 6, and 12 Amb a 1-U reduced TCS by 12% (-0.88; P = .09), 18% (-1.28; P = .01), and 27% (-1.92; P < .001) compared with placebo. Treatment was well tolerated; no systemic allergic reactions occurred.

Conclusions: In this trial, ragweed AIT of 12 Amb a 1-U was effective and tolerable with a safety profile that permitted daily self-administration of ragweed allergen immunotherapy.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Sublingual
  • Adult
  • Allergens / administration & dosage
  • Ambrosia / adverse effects
  • Ambrosia / immunology
  • Antigens, Plant / administration & dosage*
  • Antigens, Plant / adverse effects
  • Desensitization, Immunologic / adverse effects
  • Desensitization, Immunologic / methods*
  • Double-Blind Method
  • Female
  • Humans
  • Hypersensitivity, Immediate / immunology
  • Hypersensitivity, Immediate / therapy*
  • Male
  • Middle Aged
  • Plant Proteins / administration & dosage*
  • Plant Proteins / adverse effects
  • Pollen / adverse effects
  • Rhinitis, Allergic, Seasonal / immunology
  • Rhinitis, Allergic, Seasonal / therapy*
  • Self Administration
  • Tablets


  • Allergens
  • Amb a I protein, Ambrosia artemisiifolia
  • Antigens, Plant
  • Plant Proteins
  • Tablets

Supplementary concepts

  • Ragweed Sensitivity