A Study to Assess the Efficacy and Safety of PG-011 Nasal Spray in Adults With Moderate to Severe Seasonal Allergic Rhinitis

The study is a multicenter, randomized, double-blind, placebo-controlled seamless and adaptive-designed phase IIb/III study encompassing a phase IIb and a phase III component. The phase IIb study, which is registered this time, is a dose-ranging component. The phase III study is a pivotal part of the overall research. The goal of this phase IIb study is to evaluate the efficacy, safety, and pharmacokinetics of PG-011 nasal spray across various dosages and administration frequencies for treating adults with moderate to severe seasonal allergic rhinitis (SAR). Investigators will compare PG-011 nasal spray to a placebo (a look-alike substance that contains no drug) to see which dosage and frequency works to treat moderate to severe seasonal allergic rhinitis.