Efficacy and Safety Study of RAGWITEK™ (MK-3641) in Children With Ragweed-Induced Rhinoconjunctivitis With or Without Asthma (MK-3641-008)

Inclusion Criteria: * Is between the ages of 4 and 17 years (inclusive) at enrollment in this study and is at least 5 years old at randomization * Has a clinical history of significant ragweed pollen-induced allergic rhinitis/rhinoconjunctivitis of ≥1 year (at least 1 season for ages 4 to 6 years) or ≥2 years (at least 2 seasons for ages 7 to 17 years) duration diagnosed by a physician (with or without asthma) and have received treatment for the condition during the previous ragweed season * If female, agrees to remain abstinent or use (or have their partner use) an acceptable method of birth control within the projected duration of the study. Exclusion Criteria: * Has a clinical history of symptomatic seasonal allergic rhinitis (and/or asthma) due to another allergen, which has required regular medication during, or potentially overlapping, the ragweed season * Has a clinical history of significant symptomatic perennial allergic rhinitis and/or asthma due to an allergen to which the subject is regularly exposed during the ragweed season which would interfere with assessment of the treatment effect * Has any nasal condition that could confound the efficacy or safety assessments (e.g., nasal polyposis). * Has asthma requiring high daily doses of inhaled corticosteroids within the 6 months prior to the Screening visit * Is either \>7 years old and cannot perform reproducible FEV1 maneuvers despite coaching; OR is ≤7 years old and cannot perform reproducible FEV1 maneuvers de…