The Role of Endoscopic Intra-Gastric Botulinum Toxin-A for Obesity Treatment

Microneedle-Mediated Treatment of Obesity

Obesity has become a major public health threat, as it can cause various complications such as diabetes, cardiovascular disease, sleep apnea, cancer, and osteoarthritis. The primary anti-obesity therapies include dietary control, physical exercise, surgical interventions, and drug therapy; however, these treatments often have poor therapeutic efficacy, significant side effects, and unavoidable weight rebound. As a revolutionized transdermal drug delivery system, microneedles (MNs) have been increasingly used to deliver anti-obesity therapeutics to subcutaneous adipose tissue or targeted absorption sites, significantly enhancing anti-obese effects. Nevertheless, there is still a lack of a review to comprehensively summarize the latest progress of MN-mediated treatment of obesity. This review provides an overview of the application of MN technology in obesity, focusing on the delivery of various therapeutics to promote the browning of white adipose tissue (WAT), suppress adipogenesis, and improve metabolic function. In addition, this review presents detailed examples of the integration of MN technology with iontophoresis (INT) or photothermal therapy (PTT) to promote drug penetration into deeper dermis and exert synergistic anti-obese effects. Furthermore, the challenges and prospects of MN technology used for obesity treatment are also discussed, which helps to guide the design and optimization of MNs. Overall, this review provides insight into the development and clinical translation of MN technology for the treatment of obesity.

Intragastric botulinum toxin injection for weight loss: current trends, shortcomings and future perspective

The administration of botulinum toxin A (BTA) into the gastric wall has emerged as a novel endoscopic bariatric procedure. Although over 20 years have elapsed since the initial human trial of intragastric BTA injection, considerable debate remains surrounding the safety, efficacy, and procedural instructions of this approach. The current literature exhibits discrepancies in the methodologies employed across studies, including differences in the dosage of BTA administered, injection site, number and depth of injections, post-procedural dietary modifications, and follow-up duration. This study reviewed the state-of-the-art use of BTA for weight loss and focused on the clinical evidence of the therapeutic applications of BTA for obesity. Studies with consistent outcome measures and methodologies are necessary to thoroughly assess the potential effects of BTA on weight management.

Layer-Specific BTX-A Delivery to the Gastric Muscularis Achieves Effective Weight Control and Metabolic Improvement

The rising incidence of health-endangering obesity constantly calls for more effective treatments. Gastric intramural injection of botulinum neurotoxin A (BTX-A) as a new modality carries great promise yet inconsistent therapeutic efficacy. A layer-specific delivery strategy enabled by dissolving microneedles is hence pioneered to investigate the working site of BTX-A and the resulting therapeutic effects. The drug-loaded tips of the layer-specific gastric paralysis microneedles (LGP-MN) rapidly release and achieve uniform distribution of BTX-A within the designated gastric wall layers. In an obesity rat model, the LGP-MNs not only prove safer than conventional injection, but also demonstrate consistently better therapeutic effects with muscular layer delivery, including 16.23% weight loss (3.06-fold enhancement from conventional injection), 55.20% slower gastric emptying rate, improved liver steatosis, lowered blood lipids, and healthier gut microbiota. Further hormonal study reveals that the elevated production of stomach-derived glucagon-like peptide-1 due to the muscularis-targeting LGP-MN treatment is an important contributor to its unique glucose tolerance-improving effect. This study provides clear indication of the gastric muscularis as the most favorable working site of BTX-A for weight loss and metabolic improvement purposes, and meanwhile suggests that the LGP-MNs could serve as a novel clinical approach to treat obesity and metabolic syndromes.

[Endoscopic intragastric injection of botulinum toxin in the treatment of patients with morbid obesity: opportunities and prospects]

The authors consider modern epidemiological and demographic data on morbid obesity. Literature review is devoted to non-surgical treatment of patients with morbid obesity. The authors analyze the results of experimental and clinical studies on endoscopic intragastric injection of botulinum toxin and bariatric efficacy of this approach. The indications for endoscopic intragastric injection of botulinum toxin and advantages of this technique are clearly formulated. The authors identified the most significant criteria for objective assessment of clinical effectiveness of endoscopic intragastral injection of botulinum toxin, as well as scientific and methodological principles necessary for this technique. Clinical efficacy of intragastric injection of botulinum toxin including overweight loss, anorexigenic and gastroparetic effects indicates inconsistent results and certain unresolved problems. Thus, large-scale multiple-center randomized controlled trials and multivariate analysis are required to determine the role of endoscopic intragastric injection of botulinum toxin in complex treatment of patients with morbid obesity.

Effect of Intragastric Botulinum Type A Injection Combined with a Low-Calorie High-Protein Diet in Adults with Overweight or Obesity

(1) Background/aims: Intragastric botulinum toxin A injection (IGBI) combined with diet control is a new and effective weight loss method for grade 2 obese patients. However, the application of IGIB on overweight or obese adults still needs further research to confirm its efficacy. (2) Methods: We retrospectively collected medical data from 1 July 2021 to 1 January 2022 from a total of 71 patients without diabetes who participated in the bariatric clinic with a body mass index (BMI) > 25 kg/m2. Forty-nine participants opted for intragastric botulinum injection (IGBI) using 300 units of botulinum injected into the antrum, body, and fundus, followed with a low-calorie high-protein diet course. Another 22 people participated only in the low-calorie high-protein diet course as a placebo group. This study analyzes the weight loss percentage of the two groups. Adverse events after IGBI are also reported in a safety assessment. (3) Results: In terms of the characteristics of the two groups, the mean BMI was 29.3 kg/m2 in the IGBI group and 28.0 kg/m in the placebo group (p = 0.63 without significant difference). Comparing the percent weight loss from baseline in the two groups after 12 weeks, the IGBI group lost 11.5% of their body weight and the placebo group lost 1.8%. In terms of group analysis, the percentages of participants with a weight reduction of at least 5% for the IGBI and placebo groups were 95% and 4%, respectively. For weight reduction of at least 10%, these values for the IGBI and placebo groups were 63% and 4%, respectively. In terms of adverse events after IGBI for 12 weeks, 12 participants (24.4%) had constipation, which was the main side effect. No serious adverse events were observed during the study period. (4) Conclusion: The combination of a low-calorie high-protein diet and IGBI is an effective and safe procedure in overweight or obese adults for weight reduction, but further larger studies are needed.

Comparison of safety and efficacy of intragastric botulinum toxin-A versus gastric balloon

BACKGROUND

A prospective case-matched study was conducted to compare the safety and efficacy of endoscopic intragastric botulinum toxin-A (EIBT) versus endoscopically planned gastric balloon (EPGB), as a treatment for obesity.

METHODS

A total of 176 patients (matched for age and sex) were equally divided to undergo EIBT (n = 88) or EPGB (n = 88). Patients who received EIBT were restricted to a body mass index (BMI) of 25 to 35 kg/m², whereas a BMI >25 kg/m² was allowed in the EPGB group. The main measured outcomes were weight loss, procedure duration, complications, early satiety, and quality of life (QoL).

RESULTS

The patients were followed up for a mean of 6 months. The mean weight loss was greater in the EPGB group than in the EIBT group (15.6 kg vs. 9.3 kg, P < 0.001). However, the percentage excess weight loss and the satiety score were greater in the EIBT group (59.1% vs. 42.2%, P < 0.001; and 3.5 vs. 2.3, P < 0.001) respectively. The procedure duration was shorter for EIBT patients (10 min vs. 15 min, P < 0.001). The postoperative complication rate recorded in the EPGB group was significantly higher (30% vs. 9%, P = 0.001). Adverse symptoms lasted longer in EPGB (5.2 days vs. 0.7 days, P < 0.001). Both groups enjoyed similar improvements in QoL.

CONCLUSION

EIBT is a safe and effective treatment for mild obesity. Although the weight loss was greater in the EPGB group, the percentage excess weight loss, procedure duration, postoperative complications, and symptom duration were significantly better in the EIBT group. QoL improvement was comparable between the two groups.

Is Intragastric Botulinum Toxin A Injection Effective in Obesity Treatment?

AIMS

The objective of this prospective study was to evaluate the efficacy of intragastric botulinum toxin A (BTX-A) injection for the treatment of obesity.

MATERIALS AND METHODS

The study was performed between January and August 2019. This is a prospective study. After 6-12 hours of fasting, the patients were submitted to upper GI endoscopy under sedation for the injection of BTX-A. A total of 250 U of BTA-X was diluted with 10 ml of 0.9% saline. Injections were administered into the gastric antrum, each containing 1 ml of prepared solution (25 U BX-A + 1 ml saline). Continuous data were compared using a two-sample t-test. Statistical significance was determined as P ≤ 0.05. All statistical analysis was performed using SPSS for Windows 22.1 software (SPSS, Chicago, IL, USA).

RESULTS

A total of 56 patients were studied. Mean weight before gastric Botox was 85.25 ± 14.02, and mean weight after gastric Botox was 76.98 ± 12.68. Mean weight loss was approximately 9 kg in studied patients. BMI decreased about 3 units. The mean time for maximum weight loss was 60.39 ± 37.43 days. A total of 49 patients (87.5%) had reported decrease in appetite and early satiety. About 53.6% of patients were satisfied. No complications resulting from the endoscopic procedure were observed in this series.

CONCLUSIONS

Intragastric BTX-A injection can be beneficial in weight loss. It is a minimally invasive, cost-effective procedure, without serious side effects.

Endoscopic bariatric therapies for treating obesity: a learning curve for gastroenterologists

Obesity represents a growing public health threat. Until recently, surgery was the primary means for treating pharmacotherapy resistant obese patients. However, therapeutic endoscopy has evolved as an effective and safe alternative strategy. Particularly, endoscopic bariatric therapy (EBT) can bridge the gap in patients who do not fit the BMI criteria for surgery and fail conservative or medical therapy. Today there are many tools within the realm of EBT available to endoscopists. While there are no formal guidelines for their use, training and use of these tools are limited by the type of institution, preferences of senior endoscopists, cost, and availability. We review different EBT tools available to trainees and gastroenterologist, and the learning curves associated with them.

EUS-Guided Intragastric Injection of Botulinum Toxin A in the Preoperative Treatment of Super-Obese Patients: a Randomized Clinical Trial

BACKGROUND

Obesity is a disease that is highly prevalent in Brazil, and the associated comorbidities represent a major global public health challenge. Botulinum toxin type A (BTX-A) is a potent neurotoxin and inhibitor of gastric smooth muscle activity. In theory, BTX-A administration should promote early satiety and weight loss because it delays gastric emptying by inhibiting acetylcholine-mediated peristalsis, which is primarily responsible for gastric motility. Because results in the literature are discrepant, the efficacy of intragastric injections of BTX-A as a primary treatment for obesity remains unknown. The objective of this prospective, double-blind, single-center randomized study was to evaluate the effects of endoscopic ultrasound-guided intragastric BTX-A injections, as a bridge to bariatric surgery, in super-obese patients.

METHODS

Thirty-two super-obese patients were randomized to one of two groups: BTX-A, in which 200 units of BTX-A were injected into the gastric antrum and body; and control, in which the same injections were performed with 0.9% saline. Weight, body mass index (BMI), and loss of excess weight were measured monthly over a 6-month period. Gastric emptying scintigraphy was performed before and after the procedure.

RESULTS

The patients in both groups showed significant weight loss over the course of the study (p < 0.001). There were no statistically significant differences between the groups regarding weight loss, excess weight, total loss of excess weight, total weight loss, or change in BMI.

CONCLUSIONS

Intragastric injection of BTX-A does not appear to be an effective method of achieving preoperative weight loss in super-obese patients.