Efficacy and Long-Term Safety of Ragweed (Ambrosia Artemisiifolia) Sublingual Tablet in Adults With a History of Ragweed-Induced Rhinoconjunctivitis With or Without Asthma (Study P05233)(COMPLETED)

A Multicenter, Double-Blind, Randomized, Placebo-Controlled, Parallel-Group Study Evaluating the Efficacy and Long-Term Safety of Ragweed (Ambrosia Artemisiifolia) Sublingual Tablet (SCH 39641) in Adult Subjects With a History of Ragweed-Induced Rhinoconjunctivitis With or Without Asthma

This study will evaluate the efficacy and safety of ragweed sublingual tablet (SCH 39641/MK-3641) compared with placebo in participants with ragweed-induced rhinoconjunctivitis over a one-year period. It is expected that ragweed allergic participants on one of the active arms of the trial will have decreased allergic rhinoconjunctivitis symptoms and require less allergy rescue medications during ragweed pollen season.

Inclusion Criteria:

• Must have a clinical history of significant ragweed-induced allergic rhinoconjunctivitis of at least 2 years duration, with or without asthma and have received treatment during the previous RS.
• Must have a positive skin prick test response to Ambrosia artemisiifolia at Screening Visit.
• Must be positive for specific immunoglobulin E (IgE) against Ambrosia artemisiifolia at Screening Visit.
• Must have an forced expiratory volume in 1 second (FEV1) of at least 70% of predicted at Screening Visit.
• Safety laboratory tests and vital signs conducted at the Screening Visit must be within normal limits or clinically acceptable to the investigator/sponsor

Exclusion Criteria:

• Clinical history of symptomatic seasonal allergic rhinitis and/or asthma having received regular medication, due to another allergen during or potentially overlapping the RS.
• Clinical history of significant symptomatic perennial allergic rhinitis and/or asthma due to an allergen to which the participant is regularly exposed.
• Receipt of an immunosuppressive treatment within 3 months prior to the Screening Visit (except steroids for allergic and asthma symptoms).
• Clinical history of severe asthma.
• Asthma requiring medium or high dose inhaled corticosteroids.
• History of anaphylaxis with cardiorespiratory symptoms.
• History of chronic urticaria and angioedema.
• Clinical history of chronic sinusitis 2 years prior to the Screening Visit.
• Current severe atopic dermatitis.
• Breast-feeding, pregnant, or intending to become pregnant.
• Had previous treatment by immunotherapy with ragweed allergen or any other allergen 5 years prior to Screening Visit.
• History of allergy, hypersensitivity or intolerance to the ingredients of the investigational medicinal products (except for Ambrosia artemisiifolia), rescue medications, or self-injectable epinephrine.
• History of self-injectable epinephrine use.