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

One sublingual tablet containing 12 units of Amb a 1-U, once daily (QD) for up to 35 weeks.

One placebo sublingual tablet, QD for up to 35 weeks.

Intramuscular (IM) injection with suggested doses of 0.15 mg for participants weighing 15-30 kg (33-66 pounds) or 0.3 mg for participants weighing ≥30 kg (≥66 pounds), as needed for severe allergic reactions. Epinephrine was only provided in countries/study sites where it was a regulatory requirement.

Inhalation of albuterol 90 mcg/puff or salbutamol 100 mcg/puff metered dose inhaler (MDI), as needed as asthma rescue medication for those participants with asthma

5 mg (1 mg/mL syrup or 5 mg tablet) for participants 5 years old or 10 mg (1 mg/mL syrup or 10 mg tablet) for participants 6 to 17 years old, as needed for rhinoconjunctivitis symptoms

Opthalmic solution, 1 drop (0.1%) per affected eye twice daily (BID), as needed for rhinoconjunctivitis symptoms

Intranasal spray, at doses of 1 spray (50 mcg/ spray) per nostril for participants 5 to 11 years old or 2 sprays (50 mcg/spray) per nostril for participants 12 to 17 years old, as needed for rhinoconjunctivitis symptoms