Single-Pill Combinations: New Therapy for Type 2 Diabetes
LoBuono, Charlotte, Drug Topics
Patients with Type 2 diabetes now have therapeutic options that combine two medications in one pill. The Food & Drug Administration recently approved Metaglip (glipizide/metformin, Bristol-Myers Squibb) and Avandamet (rosiglitazone/metformin, GlaxoSmithKline).
As stated in Metaglip's package insert (PI), the drug is indicated as initial therapy, in addition to diet and exercise, to improve glycemic control in patients with Type 2 diabetes whose hyperglycemia cannot be satisfactorily controlled with diet and exercise alone. It is indicated as second-line therapy in patients with Type 2 diabetes whose hyperglycemia cannot be adequately controlled with diet, exercise, and initial treatment with a sulfonylurea or metformin.
In the case of Avandamet, it is indicated as an adjunct to diet and exercise to improve glycemic control in patients with Type 2 diabetes who are already receiving treatment with a combination of rosiglitazone and metformin or who have inadequate glycemic control on metformin alone.
Metaglip and Avandamet became available in pharmacies last month. Metaglip is available in several dosage strengths: 2.5 mg/250 mg, 2.5 mg/500 mg, and 5 mg/500 mg tablets. Avandamet comes in 1 mg/ 500 mg, 2 mg/500 mg, and 4 mg/ 500 mg tablets.
According to Barry Goldstein, M.D., PhD., director, division of endocrinology, diabetes, and metabolic diseases, Jefferson Medical College, Philadelphia, the contraindications for and adverse effects associated with Metaglip and Avandamet use are the same as those of the individual component drugs. Metaglip and Avandmet are contraindicated in patients with renal insufficiency, congestive heart failure requiring pharmacologic treatment, or acute or chronic metabolic acidosis. Both PIs have a boxed warning about the risk of lactic acidosis, due to metformin accumulation. Persons with hepatic insufficiency should avoid therapy with Metaglip or Avandamet. Adverse effects associated with Metaglip in clinical trials were diarrhea, nausea, and vomiting. Adverse effects associated with Avandamet were diarrhea and anemia.
The advantage of using combination therapy to treat Type 2 diabetes, said Goldstein, is that patients may reap additional clinical benefits from taking drugs with different, but complementary, mechanisms of action. Diabetes is so difficult to treat, said Anne Peters Harmel, M.D., professor of medicine, Keck School of Medicine, University of Southern California, Los Angeles, because patients take as many as nine different medications due to their increased risk for heart disease and stroke. …