TUESDAY, Oct. 17, 2006 (HealthDay News) -- People suffering from type 2 diabetes now have a new weapon in their arsenal.
The U.S. Food and Drug Administration Tuesday announced the approval of Januvia (sitagliptin phosphate) oral tablets, the first in a new class of drugs known as DPP-4 inhibitors.
"These DPP-4 inhibitors act to enhance the body's own ability to release insulin and thereby decrease elevations in blood sugar," said Dr. Robert Meyer, director of the Office of Drug Evaluation II in the Office of New Drugs at the FDA Center for Drug Evaluation and Research. "Type 2 diabetes is very, very common and, despite the numerous therapies already available, many people do not adequately control their blood sugar. A new option in type 2 diabetes, particularly one in a new class, is always a useful addition to therapies for diabetes."
Meyer spoke at a teleconference Tuesday to announce the approval.
Januvia is approved for use by people with type 2 diabetes that can't be controlled adequately with diet and exercise. It can be used either by itself or in combination with two other commonly prescribed oral medications for type 2 diabetes, metformin (Glucophage and other brand names) or a peroxisome proliferator-activated receptor gamma agonist (PPAR) such as Actos or Avandia.
More than 20 million people in the United States have type 2 diabetes, the most common form of the disease. People with this condition either don't produce enough insulin, or cells in the body don't utilize the hormone efficiently. Insulin is essential for transporting sugar from the blood to cells for energy. If sugar isn't cleared from the bloodstream, it can eventually lead to potentially fatal complications such as heart disease, nerve damage, kidney damage, blindness and amputations. The number of Americans with type 2 diabetes is expected to continue to climb due to the obesity epidemic.
Januvia, made by Merck & Co., blocks the activity of an enzyme (dipeptidyl peptidase IV, or DPP-4, that breaks down the proteins that increase the release of insulin. This gives the proteins more time to work, thereby enhancing blood-sugar control.
While Januvia is the first in this new class of drugs, other medicines are in the pipeline, including one from Novartis AG that may win approval later this year. Merck is also seeking approval for another pill, MK-0431, that would combine Januvia and metformin.
Merck is expected to charge $4.86 for the pills, which are taken once-a-day. Older diabetes drugs can cost as little as 50 cents a day, according to published reports.
Januvia was studied in 2,719 patients with type 2 diabetes, with follow-ups of 12 weeks to more than a year. It lowered blood sugar levels by 0.67 percent for participants in a yearlong trial, or just as much as another, older drug, glipizide. Novartis' pill, Galvus (vildagliptin), reduced blood sugar levels by 1.9 percent when used with another older drug, pioglitazone, which reduces insulin resistance.
People on Januvia also lost weight and experienced fewer episodes of extremely low blood sugar than those on glipizide, the Associated Press reported.
The most common side effects of Januvia were upper respiratory tract infection, sore throat, and diarrhea. And the drug did not cause weight gain, a problem for many diabetics. "It was neutral in terms of weight," said Dr. Mary Parks, director of the FDA's Division of Metabolism and Endocrine Products.
FDA officials said they were satisfied with the drug's safety profile.
"We have probably as much information on this drug as we would have on any other anti-diabetic drug and perhaps more," Meyer said. "We felt that the data were sufficiently reassuring that we didn't think there was any special program needed to look at post-approval safety."
But the FDA has asked Merck to conduct two studies as part of a "phase 4 commitment," looking at Januvia in combination with insulin and in combination with sulfonylurea, Parks said.
"One of the safety considerations in combining this drug with those two is just to make sure that this drug doesn't potentiate low blood sugar in an unexpected manner," Meyer said.
More information
For more about type 2 diabetes, visit the National Diabetes Information Clearinghouse.
