Buspirone does little to improve gastroparesis symptoms

Treatment with the 5-HT₁ receptor agonist buspirone in patients with gastroparesis falls short of reducing symptoms including moderate-to-severe early satiety/postprandial fullness, according to a study.

The 4-week multicentre clinical trial included 96 patients (92 percent women, 50 percent delayed gastric emptying, 39 percent diabetic) with symptoms of gastroparesis and moderate-to-severe symptoms of fullness (Gastroparesis Cardinal Symptom Index [GCSI] early satiety/postprandial fullness subscore [ES/PPF]). They were randomly assigned to treatment with either buspirone (10 mg; n=47) or placebo (n=49). Treatment was administered orally three times per day.

The primary endpoint was a change in the ES/PPF at 4 weeks. The analysis was conducted per protocol intention-to-treat ANCOVA of between-group baseline vs 4-week differences (DoD) in ES/PPF adjusted for baseline ES/PPF.

Results showed no between-group difference in ES/PPF at 4 weeks. The corresponding mean change in ES/PPF was −1.16 with buspirone vs −1.03 with placebo (mean DoD, −0.11, 95 percent confidence interval [CI], −0.68–0.45; p=0.69).

However, buspirone appeared to perform better than placebo in the subgroup of patients with severe-to-very severe bloating at baseline as opposed to those with none to moderate bloating (ES/PPF DoD, −0.65 vs 1.58; p=0.003; p=0.07 with Bonferroni correction). For individual GCSI symptoms, only bloating improved with buspirone vs placebo.

The findings suggest that patients with more severe bloating may derive more benefit from buspirone.