FDA Approves a New Treatment for Diabetes

The Food and Drug Administration has granted approval for Januvia, the first diabetes oral treatment approved in a new class of drugs known as DPP-4 inhibitors that enhance the body's own ability to lower elevated blood sugar.

Patients will use the drug, in addition to diet and exercise, to improve blood sugar levels to control type 2 diabetes. Januvia may be used alone or in combination with two other commonly prescribed oral diabetes medications, metformin or a PPAR agonist, when either of these drugs alone, along with diet and exercise, don't provide adequate blood sugar control.

Type 2 diabetes is the most common form of the disease, accounting for about 90 percent to 95 percent of all diagnosed cases of diabetes. Type 2 diabetes cases have surged in recent years, due in part to the dramatic rise in obesity. In type 2 diabetes, the body does not produce enough insulin or the cells ignore the insulin.

Insulin is necessary to take sugar, the basic fuel for cells, from the blood into the cells. Over time, high blood sugar levels can increase the risk for serious complications, including heart disease, blindness, nerve damage, and kidney damage. The drug prolongs the activity of proteins that increase the release of insulin after blood sugar rises, such as after a meal and does this by blocking an enzyme which breaks down these proteins, leading to better blood sugar control.

Januvia was examined in a total of 2,719 patients with type 2 diabetes, in studies lasting from 12 weeks to more than a year. These studies demonstrated improved blood sugar control when Januvia was used alone or in patients not satisfactorily managed with metformin or a PPAR agonist. .

As a DPP-4 inhibitor, Januvia can help increase a hormone called GLP-1. GLP-1 is produced in the gut after a meal and helps the body produce insulin, stops the liver from making too much glucose, helps with glucose moving from the blood into muscle and adipose tissue, and also signals a feeling of satiety or fullness.

Dr. Mario Ehlers, the chief medical officer at Seattle-based Pacific Biometrics notes that there is already a drug on the market that mimics the effects of GLP-1, namely Byetta, which was approved about a year ago and is co-marketed by Amylin and Lilly. Byetta, however, has to be injected twice a day, like insulin. Januvia has very similar effects as Byetta but is active as an oral tablet. Januvia appears to be less potent than Byetta but it has fewer side effects; in particular, it does not cause the nausea that is common with Byetta.

According to Ehlers, the most exciting thing about both Byetta and Januvia is that these drugs have been shown in animals to restore the function of beta-cells, which are the cells in the pancreas that produce insulin. Type 2 diabetes is thought to result from a combination of insulin resistance and failure of the beta cells to produce enough insulin to overcome resistance to the action of insulin. Indeed, progressive beta-cell failure is thought to be the main reason why type 2 diabetes progressively gets worse and patients typically have to add more oral drugs and eventually need to take insulin.

"It still has to be proven in humans, but potentially Byetta and Januvia, together with diet and exercise, may slow the progression of diabetes and might even halt or reverse the disease. This would have tremendous public health implications, and it could reduce the need for insulin shots in patients with late-stage type-2 diabetes," says Dr. Ehlers whose laboratories specializes in testing pharmaceuticals for metabolic diseases such as diabeties.

The most common side effects in clinical studies were upper respiratory tract infection, sore throat, and diarrhea.