RWJ-58643 is a β-trypsin and trypsin inhibitor used in studies to inhibit allergic inflammatory conditions. The compound was effective in reducing nasal allergy symptoms, eosinophil infiltration, and interleukin-5 (IL-5) levels at a lower dose (100 mg). However, at higher doses (300 mg and 600 mg), an increase in eosinophils and elevated IL-5 levels were observed, showing a clear dose-dependent response.