Efficacy and Safety of Bojungikgi-Tang for Persistent Allergic Rhinitis: A Randomized, Double-Blinded, Placebo-Controlled, Phase II Trial

Conventional treatments for allergic rhinitis (AR) exhibit insufficiency and long-term use-related side effects. Considering the reported anti-inflammatory and immunoregulatory effects of Bojungikgi-tang (BJIGT), we aimed to assess its efficacy on persistent AR (PAR). Patients with PAR were randomly assigned in a 1:1:1 ratio into high-dose BJIGT, standard-dose BJIGT, and placebo groups, followed by 1-week run-in and 4-week treatment periods. The primary outcome included the mean change in Total Nasal Symptom Score (TNSS), with secondary outcomes encompassing the Korean Allergic Rhinitis-Specific Quality of Life Questionnaire, biomarkers, overall assessment, TNSS by AR pattern identification, and the Sasang constitution. The mean TNSS change was more improved in the BJIGT group than in the placebo group; however, no statistically significant differences were observed. Additional interaction effect analysis revealed a statistically significant improvement in the high-dose BJIGT group compared with the placebo group from weeks 1-2 to weeks 3-4. Regarding secondary outcomes, the BJIGT group exhibited similar or improved results compared with the placebo group, showing no statistically significant differences. No serious adverse effects or clinically significant changes in safety assessments were observed. Given that this study validated clinical improvement and safety, it serves as potential groundwork for pertinent future studies.