The objectives of this study are: to confirm the superiority of TAU-284 over placebo after two weeks of administration to pediatric patients with perennial allergic rhinitis and to investigate safety of TAU-284.

This is a randomized, double-blind, placebo-controlled, 2-arm parallel-group comparative study to confirm the superiority of TAU-284 over placebo after two weeks of administration of TAU-284 (20 mg/day) or placebo to pediatric patients with perennial allergic rhinitis, with "the change from baseline in total nasal symptom score (total score for the three major nasal symptoms [sneezing, rhinorrhea, and nasal congestion])" as the primary endpoint; and to investigate safety of TAU-284.

Inclusion Criteria:

• Patients aged between 7 and 15 years
• Patients who have received a diagnosis of perennial allergic rhinitis according to the diagnostic criteria
• Patients with a mean rhinorrhea score and a mean sneezing score of at least 2 on the basis of symptoms recorded in the nasal allergy diary during the observation period etc.

Exclusion Criteria:

• Patients with vasomotor rhinitis or eosinophilic rhinitis
• Patients who have concurrent nasal disease that may affect the efficacy of TAU-284
• Patients with a history of any of the nasal surgical procedures
• Patients who have a positive result for pollen antigens which are dispersed during the study period
• Patients who have a positive result for dog dander or cat dander antigen and have a chance to touch dogs or cats.
• Patients with current or previous history of drug allergy
• Patients who concurrently have renal function abnormalities that may cause safety problems etc.