Comparative efficacy and potency of long-term therapy with glipizide or glyburide in patients with type 2 diabetes mellitus.

Abstract

BACKGROUND:

Long-term studies on the comparative efficacy and relative potency of glipizide and glyburide are sparse and controversial.

METHODS:

In a randomized prospective trial, we compared the effectiveness and relative potency of glipizide and glyburide over a 15-month period in 18 patients with type 2 diabetes mellitus (DM2) (9 on glyburide and 9 on glipizide) who were unresponsive to diet therapy. Glycemic control was assessed using 4 methods: 1) quarterly fasting plasma glucose (FPG), and 2-hour postprandial plasma glucose after a standard breakfast; 2) insulin and glucose response to Sustacal (test meal) challenge every 3 to 6 months; 3) quarterly hemoglobin A1c; and 4) intravenous glucose tolerance testing every 6 months to measure first and second phase insulin secretion. Patient characteristics were similar in each treatment group.

RESULTS:

Similar doses of glipizide (11 mg/day) or glyburide (10 mg/day) resulted in comparable reduction of FPG and hemoglobin A1c and increase in first phase insulin response to intravenous glucose tolerance testing. There was greater reduction in FPG and 2-hour postprandial plasma glucose with glipizide than with glyburide in 6 months. Contrary to the Physicians' Desk Reference, but consistent with another short-term study, our long-term study demonstrated that glipizide and glyburide are equipotent at similar doses in controlling hyperglycemia in DM2.

CONCLUSIONS:

Glipizide and glyburide are effective in controlling hyperglycemia with similar doses in DM2. Glipizide exhibits greater reduction in FPG and 2PPG at 6 months. Additional studies are needed to validate equipotency of these drugs.

• Authors: A E Kitabchi, E Kaminska, J N Fisher, A Sherman, K Pitts, A Bush, M Bryer-Ash
• Journal: The American journal of the medical sciences (Am J Med Sci) Vol. 319 Issue 3 Pg. 143-8 (Mar 2000) ISSN: 0002-9629 [Print] United States
• PMID: 10746824 (Publication Type: Clinical Trial, Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Blood Glucose
• Glycated Hemoglobin A
• Hypoglycemic Agents
• Insulin
• Glyburide
• Glipizide

Topics

• Adult
• Aged
• Blood Glucose (metabolism)
• Diabetes Mellitus, Type 2 (blood, drug therapy)
• Female
• Glipizide (therapeutic use)
• Glyburide (therapeutic use)
• Glycated Hemoglobin (metabolism)
• Humans
• Hypoglycemic Agents (therapeutic use)
• Insulin (blood)
• Male
• Middle Aged
• Postprandial Period
• Prospective Studies
• Therapeutic Equivalency
• Time Factors
• Treatment Outcome