A new slow-release hormone treatment is being touted as an alternative to gastric bypass surgery in obese patients suffering from type 2 diabetes. The novel therapy delivers three appetite-regulating hormones via a subcutaneous pump, resulting in weight loss and improved blood glucose levels.

Gastric bypass, or bariatric, surgery has long been one of the most effective ways to treat type 2 diabetes and morbid obesity. In some studies up to 90 percent of patients have reported entering diabetic remission following the procedure, but the operation is not without its risks, as with any major surgery.

Prior research investigating exactly how gastric bypass surgery results in obesity and diabetes improvements revealed an increase in levels of a trio of satiety hormones suspected as playing a major role in both blood glucose improvements and weight loss. Glucagon-like peptide 1 (GLP-1), oxyntomodulin (OXM), and peptide YY (PYY) are all secreted by the small intestine and colon in higher volumes following gastric bypass surgery. So, a new study set out to discover whether administering these hormones alone was enough to reduce body weight and improve glycemia.

The combination hormone treatment developed by the researchers has been dubbed GOP, and the new trial used a subcutaneous pump that can slowly infuse patients with the hormone mix consistently throughout the day. To better imitate the dietary fluctuations of a 24-hour cycle, the treatment was only infused for 12 hours every day.

Out of 26 obese, pre-diabetic subjects recruited for the study, 15 received the GOP hormone treatment for four weeks, while 11 received a placebo. At the end of the study period the researchers found the GOP group dropped an average of 4.4 kg (9.7 lb), while the placebo group only lost 2.2 kg (4.8 lb). Additional groups of patients were recruited to compare the effects of gastric bypass surgery and a very low-calorie diet to the GOP treatment.

Both of the alternatives unsurprisingly resulted in significantly greater weight loss after four weeks. The dieting cohort dropped, on average, 8.3 kg (18.3 lb), while the surgical group dropped 10.3 kg (22.7 kg). But, separate to the weight loss numbers, the GOP cohort displayed dramatic improvements to glucose levels, showing reductions to near-normal levels with a consistency not seen in the gastric bypass patients.

"Although the weight loss was smaller, using the GOP infusion would be preferable as it has fewer side effects than bariatric surgery," says lead author on the new study, Tricia Tan, from Imperial College London. "This result shows that it is possible to obtain some of the benefits of a gastric bypass operation without undergoing the surgery itself. If further trials are successful, in future we could potentially give this type of treatment to many more patients."

As Tan notes, more trials are certainly needed to verify these results in a larger cohort but the early data does excitingly suggest this treatment is a safe and mildly effective alternative to gastric bypass surgery, especially when considering the GOP mixtures superior effect on glucose tolerance compared to all alternatives.

"Although this is a small study our new combination hormone treatment is promising and has shown significant improvements in patients' health in only four weeks," says Tan. "Compared to other methods the treatment is non-invasive and reduced glucose levels to near-normal levels in our patients."

The new research was published in the journal Diabetes Care.