Background: R112 inhibits Syk kinase, a transducer of signaling through the Fcepsilon receptor of mast cells, blocking mast cell responses to allergic stimuli.
Objective: Examine the efficacy and safety of intranasal R112 in volunteers with symptomatic seasonal allergic rhinitis compared with a placebo in a park setting.
Methods: In this double-blind, placebo-controlled study of 319 volunteers with seasonal allergic rhinitis, 160 were randomized to intranasal R112 and 159 to a vehicle control during 2 days at 2 separate locations in spring 2004. Subjects were evaluated for symptoms of allergic rhinitis (i.e., sneezes, runny nose/sniffles, itchy nose, stuffy nose) on the basis of a possible maximum score of 32 for the Global Symptom Complex (GSC) scale. The primary outcome evaluated was the difference in the reduction in GSC (area under the curve over a period of 8 hours) from baseline between R112 and vehicle placebo.
Results: At baseline, the combined GSC was approximately 18/32 and equal between treatment groups. After 8 hours (dosing 3 mg/nostril every 4 hours x 2), R112 significantly reduced the GSC compared with placebo (7 vs 5.4 units, respectively; P = .0005). Each individual symptom combined to form the GSC was also significantly improved in the R112 group compared with control ( P < .05). As early as 45 minutes after dosing, R112 showed a significant improvement in symptoms over placebo, and the duration of action exceeded 4 hours. Adverse effects were indistinguishable between the groups and clinically insignificant.
Conclusion: Intranasal R112 was effective in this park study and is a promising new treatment for seasonal allergic rhinitis.