Safety and Efficacy of Two Doses of Tandospirone Citrate for Generalized Anxiety Disorder: A Multicenter Randomized Controlled Trial

Abstract Background This study aimed to determine the safety and efficacy of different doses of tandospirone to treat generalized anxiety disorder (GAD). Methods This parallel randomized controlled trial involved patients with GAD from eight centers in China between 01/2012 and 09/2018. Patients were randomly assigned to 60 mg/day and 30 mg/day groups. The primary endpoint was the overall response rate at the end of week 6. The secondary endpoints included significant response rate, change in Hamilton Anxiety Scale (HAMA) total score, HAMA subscale score, Hamilton Depression Scale-17 (HAMD-17), and adverse drug reactions. Results No significant difference was found in the overall response rate (65.7% vs 58.4%, P > 0.05) between 60 mg/day and 30 mg/day groups. The significant response rate (34.3% vs 22.6%, P = 0.032) was better in the 60 mg/day group. The reduction in HAMA total score, somatic anxiety factor, cardiovascular symptom factor, gastrointestinal symptom factor, and HAMD-17 score were better in the 60 mg/day group (all P < 0.05). The incidence of dizziness and gastrointestinal reactions of the 60 mg/day group was higher than that of the 30 mg/day group. However, there was no significant difference in the proportion of withdrawal due to adverse events. Conclusions For GAD treatment, the overall response rate of high-dose tandospirone was similar to that of low-dose tandospirone. The safety in the two groups was tolerable. Patients with good compliance might benefit from a high-dose regimen. Trial registration: The trial registration no. was NCT01614041(07/06/2012).