Buspirone for Early Satiety and Symptoms of Gastroparesis

This is a multi-center, randomized, double-masked, placebo-controlled, parallel treatment groups phase 2 trial to determine the effect of buspirone, a 5-hydroxytryptamine (5-HT) 1a receptor agonist, on early satiety and postprandial fullness in participants with symptoms of gastroparesis and with at least moderately severe symptoms of early satiety and/or postprandial fullness. After enrollment, participants aged 18-75 years will be treated with buspirone (10 mg three times per day) or a matching placebo for 4 weeks, followed by a 2-week post-treatment washout period. The primary outcome for the study is 4-week change (week 4 minus baseline) in the 4-item postprandial fullness/early satiety subscore (higher scores indicate worse symptoms) from the Patient Assessment of Gastrointestinal Disorders Symptom Severity Index (PAGI-SYM) Gastroparesis Cardinal Symptom Index (GCSI). We hypothesize that buspirone treatment will improve symptoms of postprandial fullness/early satiety compared to treatment with placebo, as indicated by a lower (smaller, more negative) 4-week change in the postprandial fullness/early satiety subscore in the buspirone arm compared to the placebo arm; change for a participant will be calculated as subscore at 4-weeks minus subscore at baseline.