Tandospirone citrate (SM-3997 citrate) is a potent and selective 5-HT1A receptor partial agonist (Ki : 27 nM)

5-HT1A:27 nM（ki）

Improvements in total abdominal scores were significantly larger with tandospirone than placebo at weeks 1, 2, and 4.?Significantly greater improvements in the tandospirone group were observed in upper abdominal pain (P=0.02) and discomfort (P=0.002) at week 4.?The proportion of responders was significantly greater in the active treatment arm at weeks 3 (P=0.017) and 4 (P=0.0016).?Significant improvements in STAI (P<0.0001) were reported in both arms, as well as in the majority of questions in the SF-8 (P=0.04).?No serious adverse events were reported, with similar rates in both study arms[1]

In this double-blind, placebo-controlled, multicenter study, FD patients were randomized to treatment with 10 mg t.i.d. tandospirone citrate or to placebo for 4 weeks. The primary end point was change in abdominal symptom scores. The difference in the proportion of responders (a total abdominal symptom score of 0 or 1) was also assessed. The quality-of-life questionnaire, the SF-8, and a psychological test questionnaire, the State-Trait Anxiety Inventory (STAI), were completed at baseline and at weekly intervals[1]