Health experts are unanimous that obesity or being overweight are major factors in the onset of type 2 diabetes. So it’s no surprise that researchers here and abroad are working to develop weight-loss drugs that can help people shed pounds and lessen their susceptibility to diabetes.
Currently there’s only one weight-loss drug approved for sales in the United States and United Kingdom: Xenical (generic name orlistat) a prescription drug that has a lower-dose OTC version called Alli.
But more help may be on the way. Three weight-loss drugs are in the research pipeline now: Pfizer’s OAP-189, Vivus Inc.’s Qnexa, and an as yet unnamed experimental drug from Roche Holding AG. Their effectiveness will hinge on their ability to overcome problems previous weight-loss drugs posed, including nausea, psychiatric side effects, and heart damage.
The three drugs have formidable obstacles ahead of them, including the need for further testing and rigorous performance challenges from U.S. and European drug regulators. It will take at least three years and up to seven or more before any of them comes to market.
Here’s a brief look at each:
Developed by British researchers, OAP-189 works by mimicking oxyntomodulin, an intestinal hormone the body produces when it has had enough to eat.
One of the effects of gastric bypass surgery is an increase in levels of oxyntomodulin, which leads to substantial weight loss in most patients. (The surgery has been very successful among type 2s in reducing or eliminating symptoms associated with diabetes.)
Scientists working on the drug are hopeful that it will reproduce the beneficial effects of gastric bypass surgery without the need for an operation.
In their research on humans, obese volunteers each lost an average of 5 lbs. in four weeks after receiving three daily doses of oxyntomodulin.
Pharmaceutical manufacturer Pfizer bought rights to the drug and is currently testing it on humans. So far the worst side effect of the drug is nausea.
Optimistic estimates have OAP-189 ready to reach market in five years. If it passes government scrutiny, plans call for the drug to be sold initially on a prescription-only basis to patients with diabetes.
The good news is that Vivus Inc.’s Qnexa, under development by researchers at the University of Alabama at Birmingham, has helped some obese people shed weight and keep those pounds off for two years.
The bad news is that the FDA rejected Qnexa in 2010, concerned about higher heart rates in some users and potential birth defects. However, Vivus recently submitted a new application to the FDA, hoping for the agency’s approval if the drug carries a warning that pregnant women shouldn’t take it.
The drug combines phentermine, an appetite suppressant , and topiramate, an anti-seizure drug. In experiments conducted by scientists at the University of Alabama at Birmingham, Qnexa was given to a random sample of 449 obese men and women. (A control group of 227 obese patients was given a placebo.)
After two years, the group receiving the drug lost an average of 10 percent of their starting weight, compared to a 2 percent weight loss among control group members.
Blood sugar levels among Qnexa users was lower, and the percentage of the drug’s users who later developed diabetes was half of that for the control group-2 percent versus 4 percent.
Roche Holding’s Drug
The drug under development by Roche Holding activates brown fat, a “good” fat found in small amounts in adults. The fat helps the body keep warm, and when activated lowers blood sugar levels and the amount of fat in the liver.
Scientists previously thought brown fat could only be found in babies. But recent research shows that the fat is present in small amounts in adults. Because the fat helps the body burn calories, research has focused on ways to activate it.
Experiments on mice using a hormone called FGF21 triggered brown fat’s beneficial effects in mice. In one experiment, diabetic mice that received a single injection of a drug that made their bodies more receptive to FGF21 experienced lower blood sugar levels for 30 days, as well as a 10 percent weight loss.
Scientists working on the drug say it will take years before their weight-loss approach is ready to test on humans.