Diabetes drug may help obese people eat less

Obese subjects ate nearly 1,000 fewer calories per day when they injected pramlintide, a drug approved for the treatment of insulin-dependent diabetes, before every meal, a new study shows.
The subjects were also less likely to binge eat and ate less when faced with "fast-food challenges" of deep-dish pizza, sugary sodas and ice cream.
Pramlintide is a synthetic version of the human hormone amylin, which is secreted by the pancreas along with insulin after meals. Amylin is referred to as a "satiety" hormone, meaning it signals a feeling of fullness to let the body know it is time to stop eating.
San Diego-based Amylin Pharmaceuticals makes pramlintide, which is sold under the trade name Symlin. In previous studies, the company demonstrated that people taking Symlin for 1 year lost 8 percent of their body weight. The current study was designed to evaluate how the drug contributes to weight loss.
Dr. Christian Weyer of Amylin and his colleagues randomly assigned 88 obese subjects self-injection with pramlintide or placebo before each meal for 6 weeks. During the course of the study, participants underwent three "fast-food challenges."
By the third day of the study, the subjects on pramlintide were consuming about 750 fewer calories a day than those on placebo and 990 calories a day less than before they began taking the drug. At day 43, those on pramlintide were eating about 500 fewer calories than those on placebo.
While the pramlintide-placebo calorie intake difference shrank as the patients on the drug lost weight, it remained "robust," the researchers note, which is "noteworthy" given that people typically start feeling hungrier after they lose a significant amount of weight.
The subjects on pramlintide also ate smaller portions and consumed less during the fast food challenges. The pramlintide group ate 385 fewer calories on the challenge at 44 days compared with the initial challenge on day 2, while the corresponding number for the placebo group was 109 fewer calories.
By day 44, the pramlintide group lost an average of 2 percent of their total body weight, compared with an average gain of 0.11 percent for those on placebo.
While peptide hormones like pramlintide have been shown to induce nausea, Weyer and his team point out, they used a low dose in the current study, and study participants taking the drug were not significantly more likely to feel nauseous than those on placebo.
Weyer told Reuters Health that his group is now evaluating a combination of pramlintide and leptin -- another satiety hormone -- or treating obesity. Studies in animals have found the combination produces a stronger effect than either hormone alone. The researcher said results of human studies of the hormone combination are expected this year.
SOURCE: American Journal of Physiology, Endocrinology and Metabolism, July 2007.