Amgen Therapy Slims Monkeys as Study Seeks Obesity Drug

An antibody discovered by Amgen Inc. (AMGN) researchers reduces weight and increases glucose tolerance in monkeys, according to a study, potentially opening up a new approach for treating obesity and diabetes in humans.

The obese monkeys lost about 10 percent of their body weight during the 11-week trial, according to the study, which was paid for by Amgen and published today by the journal Science Translational Medicine. The drug also lowered insulin, glucose and triglyceride levels.

“This type of antibody has not been described before,” Yang Li, an author of the study and scientific director at Thousand Oaks, California-based Amgen, said in an interview. “The significance of the antibody, even just finding it, expands our view of what antibodies could potentially do.”

The antibody mimics a metabolic hormone naturally produced in humans called Fibroblast growth factor 21. FGF21, which regulates glucose and lipid metabolism, has also been called the “starvation hormone” because it’s secreted by the liver during fasting.

A separate study by researchers at the University of Texas Southwestern Medical Center in Dallas found that mice bred to overproduce FGF21 received the benefits of dieting without having to diet. They also lived 30 percent to 40 percent longer than their peers who weren’t genetically modified. A side effect was a loss in bone density.

Making a drug from FGF21 itself has proven challenging, because its effect lasts only an hour or so when injected, Li said. The new antibody, dubbed mimAb1, was given in two injections over the course of the trial and its effects lasted for weeks, Li said.

Obesity Data

More than 78 million U.S. adults are obese, according to the Centers for Disease Control and Prevention. The condition raises the risks of diabetes, heart attacks and stroke, and costs the U.S. economy an estimated $147 billion a year in medical expenses and lost productivity, the Atlanta-based agency says on its website.

The Food and Drug Administration this year approved its first new obesity drugs, Vivus Inc.’s (VVUS) Qsymia and Arena Pharmaceuticals Inc.’s (ARNA) Belviq, since Roche Holding AG’s Xenical in 1999.

Diabetes, caused by the body’s inability to sufficiently produce the insulin needed to convert blood sugar into energy, affects almost 26 million Americans, or 8 percent of the U.S. population, according to the CDC

Li said it’s too early to say whether Amgen will pursue testing the antibody in humans.

“These profound effects are quite encouraging, and we are currently still evaluating these results,” Li said.

To contact the reporter on this story: Ryan Flinn in San Francisco at rflinn@bloomberg.net

To contact the editor responsible for this story: Reg Gale at rgale5@bloomberg.net