Treatment of obesity by endoscopic gastric intramural injection of botulinum toxin A: a randomized clinical trial.

Background/aims: Botulinum toxin A (BTX-A) is an inhibitor of muscular contractions in both striated and smooth muscle. The purpose of this study was to observe the safety and efficacy of endoscopic injections of BTX-A into the gastric wall in obese patients.

Methodology: Twenty obese patients (BMI >28 kg/m2) were randomized into two groups: Group 1 (200 U BTX-A) and Group 2 (300 U BTX-A). For each patient, 20 puncture sites were selected into the gastric wall. Body weights and BMIs were recorded and gastric emptying times were determined before treatment and 1, 4 and 12 weeks after treatment. Blood samples for cholesterol, triglycerides, insulin, leptin, motilin, peptide tyrosine (PYY) and ghrelin levels were obtained before treatment and 1, 4 and 12 weeks after treatment.

Results: Nineteen patients completed the follow-up. Both groups showed significant body weight and BMI decrease (p<0.05) with decreased TG levels. The gastric emptying times were longer than those before treatment in both groups, especially at the 1-week point (p<0.05). A significant decrease in fasting ghrelin levels in all 19 obese patients was found after BTX-A administration 4 weeks later, and PYY levels in all 19 patients decreased, especially at the 12-week point. No severe complications were observed.

Conclusions: Endoscopic multi-punctures of BTX-A including fundic injections may decrease body weight and BMI by delaying the gastric emptying time. The effect of BTX-A on ghrelin levels may also be involved in the reduction of appetite.