An experimental Diabetes drug can control blood sugar without causing weight gain or swelling, according to a small mid-stage clinical trial presented on Friday.

The pill, called metaglidasen, is designed to regulate the genes needed to improve the body’s response to insulin without activating those responsible for weight gain and fluid retention, according to its developer Metabolex Inc.

Existing insulin sensitizers commonly used to treat Type 2 diabetes, including GlaxoSmithKline Plc’s Avandia and Takeda Pharmaceutical Co.‘s Actos, can cause weight gain and edema, which may lead to or worsen heart failure.

“Metaglidasen seems to work as well as these drugs without the safety issues,” said Metabolex chief executive Harold Van Wart.

The drug was tested in a phase II trial of 217 patients with type 2, also known as adult-onset, diabetes who were also getting insulin injections. They were given either 200 mg or 400 mg of metaglidasen or a placebo once a day for 12 weeks.

The trial, presented at a San Diego meeting of the American Diabetes Association, showed that both doses of the drug reduced a measure of glucose control called A1C by 1 percentage point, compared with 0.3 of a point for the placebo group.

Metaglidasen also lowered fasting blood glucose levels by statistically significant margins.

Edema, which occurs in about 15 percent of patients with type 2 diabetes who are on insulin, was seen in 11 percent of the lower-dose metaglidasen patients, 5.8 percent for the higher dose and 16.2 percent for the group on insulin only.

Patients on the drug gained 0.5 kilograms on average, compared with 0.8 kg for the insulin-only group.

There were no cases of heart failure, Van Wart said.

The company also said both doses of metaglidasen had no significant effect on liver and muscle enzymes, kidney function or blood cell formation.

More than 18 million Americans have diabetes, in which the body does not produce enough insulin or cells ignore the insulin, which the body needs to convert food into energy. The condition can lead to debilitating or fatal complications such as heart disease, blindness, kidney disease, and amputations.

Several other companies are working to develop next-generation diabetes drugs.

Results from studies of muraglitazar, which is being developed by Bristol-Myers and Merck & Co. Inc., as well as AstraZeneca Plc’s Galida are also slated for presentation in San Diego.

Both are designed to work like Actos and Avandia in controlling blood sugar - with similar side effects - while also lowering blood fats, offering the potential to reduce cardiovascular disease in people with type 2 diabetes.

The phase 2 study of metaglidasen showed unchanged lipid levels, except for the 400 mg dose which lowered triglyceride levels by 15 percent.

Metabolex is now testing a higher 600 mg dose of the drug in a second phase 2 trial and expects to launch a phase 3 study - the final level needed for regulatory review of a drug - in the second quarter of next year, Van Wart said.

Meanwhile, the Hayward, California-based company is looking to find a pharmaceutical partner to develop the drug, he said.