Three years ago researchers at the Monell Chemical Senses Center in Philadelphia made a shocking discovery: our guts can taste sugar. Just like the tongue, the intestines and pancreas have sweetness receptors that can sense glucose and fructose.

With that knowledge, scientists at Elcelyx Therapeutics, a pharmaceutical company in San Diego, developed a drug that targets the taste receptors. The drug, now in phase II clinical trials, is a modified version of metformin, the most commonly prescribed drug for treating type 2 diabetes. Usually metformin dissolves in the stomach and travels through the blood to the liver, which then talks with the pancreas. NewMet, on the other hand, is designed to dissolve only when it reaches the pH found in the gut. On release, the drug fills up the sweet receptors there, which send signals to the pancreas to produce insulin, a hormone that regulates blood glucose levels. “We're modulating a natural signal,” says Alain Baron, president and CEO of Elcelyx.

Because of its direct route, NewMet is just as effective as metformin with half the typical dose, according to phase I results. The new pathway also reduces the amount of the drug that enters the bloodstream by 70 percent. That reduction is important because metformin can build up in the body with long-term use, and as a result, patients with kidney disease, up to 40 percent of people with type 2 diabetes, cannot take it. Their kidney is not able to filter the drug out of the blood, which can be deadly.

Baron thinks that other drugs could be modified to target the gut. A spin-off of Elcelyx is now working on a weight-loss drug, which would target the lower intestine and amplify the signals of fullness.