glipizide and metformin hcl (glipizide 2.5 mg metformin hydrochloride 250 mg) Dailymed

Absorption and Bioavailability Glipizide and Metformin HCl Tablets In a single-dose study in healthy subjects, the glipizide and metformin components of Glipizide and Metformin HCl Tablets 5 mg/500 mg were bioequivalent to coadministered GLUCOTROL ® and GLUCOPHAGE ® . Following administration of a single Glipizide and Metformin HCl Tablets 5 mg/500 mg tablet in healthy subjects with either a 20% glucose solution or a 20% glucose solution with food, there was a small effect of food on peak plasma concentration (C max ) and no effect of food on area under the curve (AUC) of the glipizide component. Time to peak plasma concentration (T max ) for the glipizide component was delayed 1 hour with food relative to the same tablet strength administered fasting with a 20% glucose solution. C max for the metformin component was reduced approximately 14% by food whereas AUC was not affected. T max for the metformin component was delayed 1 hour after food. Glipizide Gastrointestinal absorption of glipizide is uniform, rapid, and essentially complete. Peak plasma concentrations occur 1 to 3 hours after a single oral dose. Glipizide does not accumulate in plasma on repeated oral administration. Total absorption and disposition of an oral dose was unaffected by food in normal volunteers, but absorption was delayed by about 40 minutes. Metformin Hydrochloride The absolute bioavailability of a 500 mg metformin hydrochloride tablet given under fasting conditions is approximately 50% to 60%. Studies using single oral doses of metformin tablets of 500 mg and 1500 mg, and 850 mg to 2550 mg, indicate that there is a lack of dose proportionality with increasing doses, which is due to decreased absorption rather than an alteration in elimination. Food decreases the extent of and slightly delays the absorption of metformin, as shown by approximately a 40% lower peak concentration and a 25% lower AUC in plasma and a 35-minute prolongation of time to peak plasma concentration following administration of a single 850 mg tablet of metformin with food, compared to the same tablet strength administered fasting. The clinical relevance of these decreases is unknown. Distribution Glipizide Protein binding was studied in serum from volunteers who received either oral or intravenous glipizide and found to be 98% to 99% 1 hour after either route of administration. The apparent volume of distribution of glipizide after intravenous administration was 11 liters, indicative of localization within the extracellular fluid compartment. In mice, no glipizide or metabolites were detectable autoradiographically in the brain or spinal cord of males or females, nor in the fetuses of pregnant females. In another study, however, very small amounts of radioactivity were detected in the fetuses of rats given labeled drug. Metformin Hydrochloride The apparent volume of distribution (V/F) of metformin following single oral doses of 850 mg averaged 654±358 L. Metformin is negligibly bound to plasma proteins. Metformin partitions into erythrocytes, most likely as a function of time. At usual clinical doses and dosing schedules of metformin, steady state plasma concentrations of metformin are reached within 24 to 48 hours and are generally <1 μg/mL. During controlled clinical trials, maximum metformin plasma levels did not exceed 5 μg/mL, even at maximum doses. Metabolism and Elimination Glipizide The metabolism of glipizide is extensive and occurs mainly in the liver. The primary metabolites are inactive hydroxylation products and polar conjugates and are excreted mainly in the urine. Less than 10% unchanged glipizide is found in the urine. The half-life of elimination ranges from 2 to 4 hours in normal subjects, whether given intravenously or orally. The metabolic and excretory patterns are similar with the 2 routes of administration, indicating that first-pass metabolism is not significant. Metformin Hydrochloride Intravenous single-dose studies in normal subjects demonstrate that metformin is excreted unchanged in the urine and does not undergo hepatic metabolism (no metabolites have been identified in humans) nor biliary excretion. Renal clearance (see Table 1) is approximately 3.5 times greater than creatinine clearance, which indicates that tubular secretion is the major route of metformin elimination. Following oral administration, approximately 90% of the absorbed drug is eliminated via the renal route within the first 24 hours, with a plasma elimination half-life of approximately 6.2 hours. In blood, the elimination half-life is approximately 17.6 hours, suggesting that the erythrocyte mass may be a compartment of distribution. Specific Populations Patients With Type 2 Diabetes In the presence of normal renal function, there are no differences between single- or multiple-dose pharmacokinetics of metformin between patients with type 2 diabetes and normal subjects (see Table 1), nor is there any accumulation of metformin in either group at usual clinical doses. Renal Impairment The metabolism and excretion of glipizide may be slowed in patients with impaired renal function (see CONTRAINDICATIONS, WARNINGS, PRECAUTIONS , and DOSAGE AND ADMINISTRATION). In patients with decreased renal function, the plasma and blood half-life of metformin is prolonged and the renal clearance is decreased (see; also, see   WARNINGS ). Hepatic Impairment The metabolism and excretion of glipizide may be slowed in patients with impaired hepatic function (see PRECAUTIONS ). No pharmacokinetic studies have been conducted in patients with hepatic insufficiency for metformin. Geriatrics There is no information on the pharmacokinetics of glipizide in elderly patients. Limited data from controlled pharmacokinetic studies of metformin in healthy elderly subjects suggest that total plasma clearance is decreased, the half-life is prolonged, and C max is increased, when compared to healthy young subjects. From these data, it appears that the change in metformin pharmacokinetics with aging is primarily accounted for by a change in renal function (see Table 1). Table 1: Select Mean (±SD) Metformin Pharmacokinetic Parameters Following Single or Multiple Oral Doses of Metformin Pediatrics No data from pharmacokinetic studies in pediatric subjects are available for glipizide. After administration of a single oral GLUCOPHAGE 500 mg tablet with food, geometric mean metformin C max and AUC differed <5% between pediatric type 2 diabetic patients (12 - 16 years of age) and gender- and weight-matched healthy adults (20 - 45 years of age), all with normal renal function. Gender There is no information on the effect of gender on the pharmacokinetics of glipizide. Metformin pharmacokinetic parameters did not differ significantly in subjects with or without type 2 diabetes when analyzed according to gender (males=19, females=16). Similarly, in controlled clinical studies in patients with type 2 diabetes, the antihyperglycemic effect of metformin was comparable in males and females. Race No information is available on race differences in the pharmacokinetics of glipizide. No studies of metformin pharmacokinetic parameters according to race have been performed. In controlled clinical studies of metformin in patients with type 2 diabetes, the antihyperglycemic effect was comparable in whites (n=249), blacks (n=51), and Hispanics (n=24). Clinical Studies Patients with Inadequate Glycemic Control on Diet and Exercise Alone In a 24-week, double-blind, active-controlled, multicenter international clinical trial, patients with type 2 diabetes, whose hyperglycemia was not adequately controlled with diet and exercise alone (hemoglobin A 1c [HbA 1c ] >7.5% and ≤12%, and fasting plasma glucose [FPG] <300 mg/dL) were randomized to receive initial therapy with glipizide 5 mg, metformin 500 mg, Glipizide and Metformin HCl Tablets 2.5 mg/250 mg, or Glipizide and Metformin HCl Tablets 2.5 mg/500 mg. After 2 weeks, the dose was progressively increased (up to the 12-week visit) to a maximum of 4 tablets daily in divided doses as needed to reach a target mean daily glucose (MDG) of ≤130 mg/dL. Trial data at 24 weeks are summarized in Table 2. Table 2: Active-Controlled Trial of Glipizide and Metformin HCl Tablets in Patients with Inadequate Glycemic Control on Diet and Exercise Alone: Summary of Trial Data at 24 Weeks After 24 weeks, treatment with Glipizide and Metformin HCl Tablets 2.5 mg/250 mg and 2.5 mg/500 mg resulted in significantly greater reduction in HbA 1c compared to glipizide and metformin therapy. Also, Glipizide and Metformin HCl Tablets 2.5 mg/250 mg therapy resulted in significant reductions in FPG versus metformin therapy. Increases above fasting glucose and insulin levels were determined at baseline and final study visits by measurement of plasma glucose and insulin for 3 hours following a standard mixed liquid meal. Treatment with Glipizide and Metformin HCl Tablets lowered the 3-hour postprandial glucose AUC, compared to baseline, to a significantly greater extent than did the glipizide and the metformin therapies. Compared to baseline, Glipizide and Metformin HCl Tablets enhanced the postprandial insulin response, but did not significantly affect fasting insulin levels. There were no clinically meaningful differences in changes from baseline for all lipid parameters between Glipizide and Metformin HCl Tablets therapy and either metformin therapy or glipizide therapy. The adjusted mean changes from baseline in body weight were: Glipizide and Metformin HCl Tablets 2.5 mg/250 mg, -0.4 kg; Glipizide and Metformin HCl Tablets 2.5 mg/500 mg, -0.5 kg; glipizide, -0.2 kg; and metformin, -1.9 kg. Weight loss was greater with metformin than with Glipizide and Metformin HCl Tablets. Patients with Inadequate Glycemic Control on Sulfonylurea Monotherapy In an 18-week, double-blind, active-controlled U.S. clinical trial, a total of 247 patients with type 2 diabetes not adequately controlled (HbA 1c ≥7.5% and ≤12%, and FPG <300 mg/dL) while being treated with at least one-half the maximum labeled dose of a sulfonylurea (eg, glyburide 10 mg, glipizide 20 mg) were randomized to receive glipizide (fixed dose, 30 mg), metformin (500 mg), or Glipizide and Metformin HCl Tablets 5 mg/500 mg. The doses of metformin and Glipizide and Metformin HCl Tablets were titrated (up to the 8-week visit) to a maximum of 4 tablets daily as needed to achieve MDG ≤130 mg/dL. Trial data at 18 weeks are summarized in Table 3. Table 3: Glipizide and Metformin HCl Tablets in Patients with Inadequate Glycemic Control on Sulfonylurea Alone: Summary of Trial Data at 18 Weeks After 18 weeks, treatment with Glipizide and Metformin HCl Tablets at doses up to 20 mg/2000 mg per day resulted in significantly lower mean final HbA1c and significantly greater mean reductions in FPG compared to glipizide and metformin therapy. Treatment with Glipizide and Metformin HCl Tablets lowered the 3-hour postprandial glucose AUC, compared to baseline, to a significantly greater extent than did the glipizide and the metformin therapies. Glipizide and Metformin HCl Tablets did not significantly affect fasting insulin levels. There were no clinically meaningful differences in changes from baseline for all lipid parameters between Glipizide and Metformin HCl Tablets therapy and either metformin therapy or glipizide therapy. The adjusted mean changes from baseline in body weight were: Glipizide and Metformin HCl Tablets 5 mg/500 mg, -0.3 kg; glipizide, -0.4 kg; and metformin, -2.7 kg. Weight loss was greater with metformin than with Glipizide and Metformin HCl Tablets.



Teratogenic Effects: Pregnancy Category C Recent information strongly suggests that abnormal blood glucose levels during pregnancy are associated with a higher incidence of congenital abnormalities. Most experts recommend that insulin be used during pregnancy to maintain blood glucose as close to normal as possible. Because animal reproduction studies are not always predictive of human response, Glipizide and Metformin HCl Tablets should not be used during pregnancy unless clearly needed. (See below.) There are no adequate and well-controlled studies in pregnant women with Glipizide and Metformin HCl Tablets or its individual components. No animal studies have been conducted with the combined products in Glipizide and Metformin HCl Tablets. The following data are based on findings in studies performed with the individual products. Glipizide Glipizide was found to be mildly fetotoxic in rat reproductive studies at all dose levels (5-50 mg/kg). This fetotoxicity has been similarly noted with other sulfonylureas, such as tolbutamide and tolazamide. The effect is perinatal and believed to be directly related to the pharmacologic (hypoglycemic) action of glipizide. In studies in rats and rabbits, no teratogenic effects were found. Metformin Hydrochloride Metformin alone was not teratogenic in rats or rabbits at doses up to 600 mg/kg/day. This represents an exposure of about 2 and 6 times the MRHD dose of 2000 mg of the metformin component of Glipizide and Metformin HCl Tablets based on body surface area comparisons for rats and rabbits, respectively. Determination of fetal concentrations demonstrated a partial placental barrier to metformin. Nonteratogenic Effects Prolonged severe hypoglycemia (4-10 days) has been reported in neonates born to mothers who were receiving a sulfonylurea drug at the time of delivery. This has been reported more frequently with the use of agents with prolonged half-lives. It is not recommended that Glipizide and Metformin HCl Tablets be used during pregnancy. However, if it is used, Glipizide and Metformin HCl Tablets should be discontinued at least 1 month before the expected delivery date. ( See Pregnancy: Teratogenic Effects: Pregnancy Category C .)

Although it is not known whether glipizide is excreted in human milk, some sulfonylurea drugs are known to be excreted in human milk. Studies in lactating rats show that metformin is excreted into milk and reaches levels comparable to those in plasma. Similar studies have not been conducted in nursing mothers. Because the potential for hypoglycemia in nursing infants may exist, a decision should be made whether to discontinue nursing or to discontinue Glipizide and Metformin HCl Tablets, taking into account the importance of the drug to the mother. If Glipizide and Metformin HCl Tablets are discontinued, and if diet alone is inadequate for controlling blood glucose, insulin therapy should be considered.