Effect of pioglitazone on metabolic syndrome risk factors: results of double-blind, multicenter, randomized clinical trials

OBJECTIVE: To evaluate the effect of pioglitazone, metformin, and/or sulfonylurea on metabolic syndrome and its component parameters after a year of treatment. METHODS: Adult patients with poorly controlled type 2 diabetes were enrolled in 4 multicenter, double-blind studies and received pioglitazone, sulfonylurea, metformin, or a combination of any 2 agents. Post hoc analyses were performed on data from patients with evaluations at baseline and week 52, and treatment groups were compared to determine change from baseline in metabolic syndrome status and its component variables by using the McNemar test and analysis of covariance, respectively. RESULTS: Most patients (72.1%) had metabolic syndrome at baseline. Change in the proportion of patients with metabolic syndrome status was significant in each monotherapy and the pioglitazone plus metformin combination groups. Pioglitazone alone or in combination with metformin resulted in a significantly greater percent decrease from baseline in triglycerides (pioglitazone vs. metformin, 10.3%; pioglitazone vs. sulfonylurea, 6.5%; pioglitazone plus metformin vs. sulfonylurea plus metformin, 13.4%; P < 0.05) and a greater percent increase from baseline in high-density lipoprotein (HDL) cholesterol (pioglitazone vs. metformin, 9.1%; pioglitazone vs. sulfonylurea, 12.6%; pioglitazone plus metformin vs. sulfonylurea plus metformin, 17.8%; P < 0.001) at week 52 than did the respective comparison groups. A significant decrease from baseline in the ratio of urinary albumin to creatinine was found only with pioglitazone monotherapy (-1.764 mg/ mmol; P < 0.001), which was significantly greater than the change in the metformin monotherapy group (2.1%; P < 0.05). Significant decrease in blood pressure was observed in the pioglitazone monotherapy and pioglitazone plus sulfonylurea groups, with no significant treatment group differences. CONCLUSIONS: Treatment with pioglitazone as monotherapy or combination therapy led to sustained, positive effects on important components of metabolic syndrome in patients with type 2 diabetes, independent of effects on blood glucose control and, as such, could be translated to potential for reducing the risk of cardiovascular disease.     

Glycemic control and treatment failure with pioglitazone versus glibenclamide in type 2 diabetes mellitus: a 42-month, open-label, observational, primary care study

BACKGROUND: Insulin resistance and declining beta-cell function are the core defects in type 2 diabetes mellitus. It has been suggested that deteriorating glycemic control is related to baseline hemoglobin A(1c) (HbA(1c)) values and remaining beta-cell function. PATIENTS AND METHODS: We report glycemic data from a 3.5-year, open-label, observational, primary care study comparing 30 mg/day pioglitazone with 3.5 mg/day glibenclamide add-on to stable metformin monotherapy in 500 patients with type 2 diabetes. Insulin commencement was considered for patients with HbA(1c) > or = 8.0% or when vascular complications occurred. The change in HbA(1c) compared with baseline and the difference in time to failure to maintain glycemic control were calculated. RESULTS: At endpoint, HbA(1c) had decreased by 1.0% in the pioglitazone group (p < 0.005) and by 0.6% in the glibenclamide group (p < 0.05). Annual progression rates to insulin treatment were 6.6% (pioglitazone) and 16.4% (glibenclamide; p < 0.001 between-group difference). Mean weight increases of 3.5 +/- 0.42 kg in the pioglitazone group and 3.3 +/- 0.38 kg in the glibenclamide group were noted. Overall, both treatments were well tolerated. CONCLUSIONS: Pioglitazone add-on to metformin revealed significant benefits in long-term glycemic control compared with glibenclamide. This difference may be explained by a large between-group difference in HOMA-S, which was shown to correlate significantly to the change in HbA(1c). This suggests that a strategy to reduce insulin resistance to lower the burden of the beta-cell is superior to treatment with glibenclamide.     

Effect of pioglitazone on metabolic syndrome risk factors: results of double-blind,multicenter, randomized clinical trials

ABSTRACT

Objective: To evaluate the effect of pioglitazone, metformin, and/or sulfonylurea on metabolic syndrome and its component parameters after a year of treatment.

Methods: Adult patients with poorly controlled type 2 diabetes were enrolled in 4 multicenter, double-blind studies and received pioglitazone, sulfonylurea, metformin, or a combination of any 2 agents. Post hoc analyses were performed on data from patients with evaluations at baseline and week 52, and treatment groups were compared to determine change from baseline in metabolic syndrome status and its component variables by using the McNemar test and analysis of covariance, respectively.

Results: Most patients (72.1%) had metabolic syndrome at baseline. Change in the proportion of patients with metabolic syndrome status was significant in each monotherapy and the pioglitazone plus metformin combination groups. Pioglitazone alone or in combination with metformin resulted in a significantly greater percent decrease from baseline in triglycerides (pioglitazone vs. metformin, 10.3%; pioglitazone vs. sulfonylurea, 6.5%; pioglitazone plus metformin vs. sulfonylurea plus metformin, 13.4%; P < 0.05) and a greater percent increase from baseline in high-density lipoprotein (HDL) cholesterol (pioglitazone vs. metformin, 9.1%; pioglitazone vs. sulfonylurea, 12.6%; pioglitazone plus metformin vs. sulfonylurea plus metformin, 17.8%; P < 0.001) at week 52 than did the respective comparison groups. A significant decrease from baseline in the ratio of urinary albumin to creatinine was found only with pioglitazone monotherapy (–1.764?mg/mmol; P < 0.001), which was significantly greater than the change in the metformin monotherapy group (2.1%; P < 0.05). Significant decrease in blood pressure was observed in the pioglitazone monotherapy and pioglitazone plus sulfonylurea groups, with no significant treatment group differences.

Conclusions: Treatment with pioglitazone as monotherapy or combination therapy led to sustained, positive effects on important components of metabolic syndrome in patients with type 2 diabetes, independent of effects on blood glucose control and, as such, could be translated to potential for reducing the risk of cardiovascular disease.     

Pioglitazone: a review of Japanese clinical studies

Pioglitazone, a new thiazolidinedione agent,has been shown to increase insulin sensitivity in clinical trials. Pioglitazone HCI was rapidly absorbed within one hour, achieved peak concentrations at 2-3 h, and was eliminated from serum at 24-36 h. Pioglitazone demonstrated dose-dependent pharmacokinetics. Food did not significantly affect the pharmacokinetic profile of pioglitazone. The pharmacokinetic profile of sulfonylurea agents was not significantly altered by concurrent administration with pioglitazone. Pharmacokinetic studies in healthy volunteers and in patients with type 2 diabetes indicated that pioglitazone may be administered once daily. In patients with type 2 diabetes, pioglitazone as monotherapy and in combination with sulfonylureas or an alpha-glucosidase inhibitor significantly reduced fasting blood glucose, HbA1c, triglycerides, and free fatty acids, and significantly increased HDL-cholesterol. Pioglitazone demonstrated either minor increases or decreases in cholesterol with no adverse effect on LDL-cholesterol. No patients experienced jaundice or ALT elevations > or = three times the upper limit of normal. Adverse events were mild and transient; all subjects returned to their baseline health status or laboratory tests upon withdrawal from, or completion of, the studies. Based upon these preliminary studies, full-scale clinical investigations were conducted in Japan, the United States, and Europe. As a result, in many countries pioglitazone has gained approval for use in patients with type 2 diabetes.     

Linagliptin: in type 2 diabetes mellitus

Linagliptin, a novel dipeptidyl peptidase-4 (DPP-4) inhibitor, has a favourable pharmacokinetic profile in terms of its predominantly non-renal elimination. It shows highly selective, potent, dose-dependent inhibition of DPP-4, with ≥ 80% inhibition of DPP-4 throughout the 24-hour dosing interval. In two double-blind, multicentre trials (n?>350 evaluable patients/trial) in adult patients with inadequately controlled type 2 diabetes mellitus, oral linagliptin monotherapy (5 or 10?mg once daily) was significantly more effective than placebo in improving glycaemic control and several parameters of pancreatic function, with placebo-corrected adjusted mean changes in glycosylated haemoglobin (HbA(1c)) levels of -0.69% to -0.88% after 12 or 24 weeks. Linagliptin 5 or 10?mg once daily was also significantly more efficacious than voglibose 0.2?mg three times daily in terms of improving glycaemic control in a 26-week, double-blind, multicentre trial (n?>450 evaluable patients). In several similarly designed trials (n?>250 evaluable patients/trial) of 12-24 weeks' duration in adult patients with inadequately controlled type 2 diabetes, oral linagliptin (5?mg once daily) as add-on therapy to metformin, a sulfonylurea drug or metformin plus a sulfonylurea drug, or in combination with pioglitazone, improved glycaemic control significantly more than placebo plus the respective oral antihyperglycaemic therapy, with improvements in adjusted mean HbA(1c) levels considered clinically relevant. Linagliptin, as monotherapy or in combination with other oral antihyperglycaemic drugs, was generally well tolerated in clinical trials, having neutral or minimal effects on bodyweight and generally being associated with a very low incidence of hypoglycaemia.     

Update: vildagliptin for the treatment of Type 2 diabetes

Vildagliptin is a selective inhibitor of dipeptidyl peptidase-4, and prevents the rapid degradation of the incretin hormones glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. Vildagliptin has been evaluated in > 4800 patients in nine Phase III studies in the range of 24 - 52 weeks in duration: four placebo- or active-controlled monotherapy trials that enrolled drug-naive patients; four add-on studies in which vildagliptin was added to a stable regimen of either metformin, a sulfonylurea, a thiazolidinedione or insulin; and a study in which an initial combination of vildagliptin plus pioglitazone in drug-naive patients was evaluated. Across studies, vildagliptin was effective in reducing HbA(1c), had a low risk of hypoglycemia and was weight-neutral and well tolerated.     

Pioglitazone: A Review of Japanese Clinical Studies

Summary

Pioglitazone, a new thiazolidinedione agent, has been shown to increase insulin sensitivity in clinical trials. Pioglitazone HCl was rapidly absorbed within one hour, achieved peak concentrations at 2–3?h, and was eliminated from serum at 24–36?h. Pioglitazone demonstrated dose-dependent pharmacokinetics. Food did not significantly affect the pharmacokinetic profile of pioglitazone. The pharmacokinetic profile of sulfonylurea agents was not significantly altered by concurrent administration with pioglitazone. Pharmacokinetic studies in healthy volunteers and in patients with type 2 diabetes indicated that pioglitazone may be administered once daily. In patients with type 2 diabetes, pioglitazone as monotherapy and in combination with sulfonylureas or an α-glucosidase inhibitor significantly reduced fasting blood glucose, HbA1c, triglycerides, and free fatty acids, and significantly increased HDL-cholesterol. Pioglitazone demonstrated either minor increases or decreases in cholesterol with no adverse effect on LDL-cholesterol. No patients experienced jaundice or ALT elevations > three times the upper limit of normal. Adverse events were mild and transient; all subjects returned to their baseline health status or laboratory tests upon withdrawal from, or completion of, the studies. Based upon these preliminary studies, full-scale clinical investigations were conducted in Japan, the United States, and Europe. As a result, in many countries pioglitazone has gained approval for use in patients with type 2 diabetes.     

Pioglitazone/metformin

A fixed-dose pioglitazone/metformin tablet is approved in the US and the EU for the treatment of adult patients with type 2 diabetes mellitus who currently have inadequate glycaemic control with metformin monotherapy. In the US, the combination tablet is also approved for the treatment of adult patients with type 2 diabetes who currently have inadequate glycaemic control with pioglitazone monotherapy and for those already receiving a combination of pioglitazone and metformin. Bioequivalence, based on absorption and bioavailability parameters, has been established between the fixed-dose tablets and equivalent doses of pioglitazone and metformin coadministered as separate agents. Combination therapy with pioglitazone plus metformin was significantly more effective at improving both glycaemic and lipid control than metformin plus placebo in patients with type 2 diabetes in a 16-week, well designed trial. Pioglitazone plus metformin demonstrated similar antihyperglycaemic efficacy to that of rosiglitazone plus metformin in a well designed 12-month trial; however, pioglitazone plus metformin was the superior combination in terms of lipid control. In several comparative trials of 1-3.5 years' duration, pioglitazone plus metformin was at least as effective as combination therapy with a sulphonylurea plus metformin in terms of antihyperglycaemic efficacy, but provided superior lipidaemic control with regard to levels of triglyceride and high-density lipoprotein-cholesterol. Pioglitazone plus metformin was generally well tolerated in patients with type 2 diabetes, with adverse events common to metformin monotherapy observed at a similar incidence to that with metformin plus placebo.     

Linagliptin: a review of its use in the management of type 2 diabetes mellitus

Linagliptin (Trajenta?, Tradjenta?, Trazenta?, Trayenta?) is an oral, highly selective inhibitor of dipeptidyl peptidase-4 and is the first agent of its class to be eliminated predominantly via a nonrenal route. Linagliptin is indicated for once-daily use for the treatment of adults with type 2 diabetes mellitus, and a twice-daily fixed-dose combination of linagliptin/metformin (Jentadueto?) is also available. In this article, the pharmacological, clinical efficacy and tolerability data relevant to the use of linagliptin in patients with type 2 diabetes are reviewed. The efficacy of oral linagliptin in the treatment of adults with type 2 diabetes has been investigated in several double-blind, multicentre trials. Following 12-24 weeks of treatment, improvements in glycaemic control parameters, including glycosylated haemoglobin (HbA(1c); primary endpoint in all trials), were seen with linagliptin relative to placebo when used as monotherapy, initial combination therapy (with metformin or pioglitazone) or add-on therapy to other oral antihyperglycaemia agents (metformin and/or a sulfonylurea) or basal insulin (with or without metformin and/or pioglitazone). In terms of lowering HbA(1c), linagliptin was more effective than voglibose in a 26-week monotherapy trial and noninferior to glimepiride when used as add-on therapy to metformin in a 104-week study. Additional trials and subgroup analyses of pooled data suggest that linagliptin improves glycaemic control regardless of factors such as age, duration of type 2 diabetes, ethnicity and renal function, and as linagliptin is eliminated primarily via a nonrenal route, it can be used without dosage adjustment in patients with renal impairment of any degree. Oral linagliptin was generally well tolerated and was associated with a low likelihood of hypoglycaemia (except when used in combination with a sulfonylurea) and had little effect on bodyweight. Further long-term and comparative efficacy and tolerability data are required to help position linagliptin more definitively with respect to other antihyperglycaemia agents. However, clinical data currently available indicate that linagliptin is an effective and generally well tolerated treatment option for use in patients with type 2 diabetes, including those with renal impairment for whom other antihyperglycaemia agents require dosage adjustment or are not suitable.     

Vildagliptin: a review of its use in the management of type 2 diabetes mellitus

Vildagliptin (Galvus) is an antihyperglycaemic agent that selectively inhibits the dipeptidyl peptidase-4 (DPP-4) enzyme. Such inhibition prevents the degradation of the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). This results in improved glycaemic control as determined by glycated haemoglobin (HbA(1c)) and fasting plasma glucose (FPG) levels, and, in addition, an enhancement of pancreatic alpha- and beta-cell function. Vildagliptin is indicated in the EU and elsewhere in the world for the management of type 2 diabetes mellitus in combination with metformin, a sulfonylurea or a thiazolidinedione in patients with inadequate glycaemic control following monotherapy. Vildagliptin is also available as a fixed-dose formulation with metformin (Eucreas).Oral vildagliptin in combination with metformin, a sulfonylurea or a thiazolidinedione improved glycaemic control in adults with type 2 diabetes and appeared to slow the progression of beta-cell degeneration in trials of 24-52 weeks' duration. In trials in patients with diabetes inadequately controlled with metformin, vildagliptin provided an additional reduction of HbA(1c) levels of 1.1% and was shown to be as effective as pioglitazone as add-on therapy in a noninferiority trial. Vildagliptin had a low risk of hypoglycaemia, was weight-neutral overall and was generally well tolerated. Further investigation is required to accurately position vildagliptin relative to other, well established antidiabetic agents. However, the addition of vildagliptin expands the range of treatment options available, and as such, offers further potential for the management of patients with type 2 diabetes that is inadequately controlled with monotherapy.     

Pioglitazone and rosiglitazone for diabetes

Pioglitazone (Actos-Takeda) and rosiglitazone (Avandia-GlaxoSmithKline) belong to a new class of oral antidiabetic medicines (the glitazones or thiazolidinediones). Both are licensed in the UK for "oral combination treatment of type 2 diabetes mellitus in [narrowly defined groups of] patients with insufficient glycaemic control despite maximal tolerated dose of oral monotherapy with either metformin or a sulphonylurea". They are not licensed for use as monotherapy, in combination with insulin, or as part of triple therapy with metformin or a sulphonylurea. What can pioglitazone and rosiglitazone offer in the management of patients with type 2 diabetes?     

Efficacy and safety of therapy with metformin plus pioglitazone in the treatment of patients with type 2 diabetes: a double-blind,placebo-controlled,clinical trial

ABSTRACT

Objective: To assess the efficacy and safety of combination therapy with pioglitazone and metformin in Japanese patients with type 2 diabetes.

Research design and methods: During a 12-week observation period 236 patients were treated with metformin 500 or 750?mg/day. 169 patients with a confirmed HbA_1c level ≥ 6.5% were randomized (stratified according to metformin dosage) to receive pioglitazone 15?mg/day for 12 weeks then increased to 30?mg/day for a further 16 weeks (n?=?83), or placebo (n?=?86). Outcome measures included HbA_1c, fasting blood glucose (FBG), percentage of patients achieving HbA_1c?<?6.5%, lipid profile, and other metabolic parameters.

Results: Mean HbA_1c was reduced by 0.67% in patients receiving pioglitazone plus metformin versus an increase of 0.25% in those receiving metformin alone (p?<?0.0001). After 8 weeks’ treatment and until the end of the study, HbA_1c was significantly lower with pioglitazone plus metformin and more patients in this group achieved an HbA_1c?<?6.5% (38.6% vs. 8.1%; p?<?0.0001). FBG was also reduced by a significantly greater amount in patients receiving pioglitazone plus metformin compared with metformin monotherapy (?20.5 vs. 1.9?mg/dl; p?<?0.0001). Combination therapy was associated with significantly increased HDL-cholesterol, total cholesterol, and adiponectin, and significantly decreased levels of fasting insulin, free fatty acids, and homeostasis model assessment insulin resistance (HOMA-R) compared with metformin monotherapy. Overall, combination therapy and monotherapy were equally well tolerated and the incidence of adverse effects ‘possibly’ related to therapy was 15.7% and 11.6% (p?=?0.505), respectively. Edema occurred slightly more often in the combination group (6.0 vs. 1.2%).

Conclusion: Pioglitazone plus metformin significantly improved glycemic control (HbA_1c and FBG), and markers associated with increased insulin resistance and cardiovascular risk compared with metformin monotherapy.

Clinical trial registration number: UMIN 000001110.     

Saxagliptin: a review of its use as combination therapy in the management of type 2 diabetes mellitus in the EU

Saxagliptin (Onglyza?) is a dipeptidyl peptidase 4 inhibitor widely approved for the treatment of type 2 diabetes mellitus. In the EU, saxagliptin is indicated as combination therapy with metformin, a sulfonylurea, a thiazolidinedione, or insulin (with or without metformin) for the treatment of adult patients with type 2 diabetes, including those with mild to severe renal impairment. This article reviews the clinical efficacy and tolerability of add-on saxagliptin therapy in patients with type 2 diabetes, in line with its approved indications in the EU, and summarizes the drug's pharmacological properties. The clinical efficacy of saxagliptin 5?mg/day in combination with metformin, glibenclamide (glyburide), a thiazolidinedione, or insulin (with or without metformin) has been demonstrated in several randomized, double-blind, placebo-controlled, multicentre, phase III trials (18-104 weeks in duration) in patients with type 2 diabetes. In these trials, glycosylated haemoglobin (HbA(1c)) was changed from baseline (primary endpoint) by a greater extent with add-on saxagliptin 5?mg/day (-1.09% to +0.03%) than with comparator regimens (-0.44% to +0.69%). Two other randomized, double-blind trials showed that saxagliptin 5?mg/day as add-on therapy to metformin was noninferior to uptitrated glipizide in terms of lowering HbA(1c) (-0.74% vs -0.80%) at 52 weeks, or sitagliptin (-0.52% vs -0.62%) at 18 weeks. Saxagliptin 2.5?mg/day as add-on to existing anti-diabetic therapy was also effective for up to 52 weeks in a randomized, double-blind, placebo-controlled, multicentre trial in patients with type 2 diabetes and renal impairment (HbA(1c) was reduced by 1.08% vs 0.36%; p?≤?0.007). Saxagliptin as add-on therapy for up to 4 years was generally well tolerated in clinical trials. Treatment with saxagliptin did not increase the risk of hypoglycaemia or cardiovascular outcomes relative to placebo or active comparators, and was generally weight neutral. In conclusion, saxagliptin is a useful option as add-on therapy to metformin, a sulfonylurea, a thiazolidinedione, or insulin (with or without metformin) in patients with type 2 diabetes who require combination therapy.     

Vildagliptin: a review of its use in type 2 diabetes mellitus

Vildagliptin (Galvus?, Jalra?, Xiliarx?) is an orally administered dipeptidyl peptidase-4 (DPP-4) inhibitor. In patients with type 2 diabetes mellitus, vildagliptin 50?mg twice daily is indicated for use in combination with metformin or a thiazolidinedione, and vildagliptin 50?mg once daily is indicated for use in combination with a sulfonylurea. A fixed-dose combination of vildagliptin/metformin (Eucreas?, Icandra?, Zomarist?) is also available. This article reviews the clinical efficacy and tolerability of vildagliptin in patients with type 2 diabetes, as well as summarizing its pharmacological properties. The efficacy of monotherapy or combination therapy with oral vildagliptin in patients with type 2 diabetes has been examined in randomized, double-blind, multicentre trials. Monotherapy with vildagliptin 50?mg once or twice daily reduced glycosylated haemoglobin (HbA(1c)) from baseline to a significantly greater extent than placebo, according to the results of 12- to 52-week trials in patients with type 2 diabetes. In terms of the reduction from baseline in HbA(1c) seen in active comparator trials of 12-104 weeks' duration, the noninferiority of vildagliptin 50?mg twice daily was established versus acarbose or rosiglitazone, the noninferiority of vildagliptin 100?mg once daily (an off-label dosage) versus metformin was established in elderly patients and vildagliptin 50?mg twice daily was more effective than voglibose; however, the noninferiority of vildagliptin 50?mg twice daily versus metformin or gliclazide was not established in two other trials. Combination therapy with vildagliptin 50?mg twice daily plus metformin improved HbA(1c) to a significantly greater extent than monotherapy with metformin and/or vildagliptin alone in patients with type 2 diabetes whose disease was inadequately controlled by metformin monotherapy or who were treatment naive, according to the results of 12- or 24-week trials. In addition, vildagliptin 50?mg twice daily plus metformin demonstrated noninferiority to pioglitazone plus metformin, glimepiride plus metformin or gliclazide plus metformin in terms of the change from baseline in HbA(1c) after 24 or 52 weeks' therapy in patients with inadequately controlled type 2 diabetes. The addition of vildagliptin 50?mg twice daily to pioglitazone or vildagliptin 50?mg once daily to glimepiride improved HbA(1c) to a significantly greater extent than a thiazolidinedione or glimepiride alone in patients with type 2 diabetes whose disease was inadequately controlled, according to the results of 24-week trials. Oral vildagliptin 50?mg once or twice daily was generally well tolerated in patients with type 2 diabetes. In particular, vildagliptin was associated with a low risk of hypoglycaemia and was weight neutral. Increases in transaminase levels were sometimes observed with a vildagliptin dosage of 100?mg once daily in clinical trials, and liver function should be monitored in patients receiving vildagliptin. However, meta-analyses of clinical trial data suggested that vildagliptin 50?mg once or twice daily was not associated with an increased risk of hepatic adverse events, transaminase elevations ≥3?×?the upper limit of normal, pancreatitis, cardiovascular or cerebrovascular events, infections or skin-related toxicity. In conclusion, vildagliptin is an important option for use in combination with metformin, a sulfonylurea or a thiazolidinedione in patients with type 2 diabetes who require combination therapy.     

Glimepiride versus pioglitazone combination therapy in subjects with type 2 diabetes inadequately controlled on metformin monotherapy: results of a randomized clinical trial

OBJECTIVE: To compare the effect of add-on glimepiride or pioglitazone in subjects with type 2 diabetes inadequately controlled on metformin monotherapy. RESEARCH DESIGN AND METHODS: Multicenter, randomized, parallel-group, open-label, forcedtitration study involving 203 adults with poorly controlled type 2 diabetes (A1C 7.5-10%) on metformin monotherapy. Subjects were randomized to receive glimepiride or pioglitazone, titrated to the maximum dose for 26 weeks. Subjects were evaluated for A1C changes, fasting plasma glucose (FPG), insulin, C-peptide, and lipid levels. Safety outcomes and diabetes-related healthcare resource utilization were also evaluated. RESULTS: Both treatment groups achieved similar and significant mean decreases from baseline to endpoint (week 26) in A1C (p = 0.0001) and FPG (p < 0.05). Glimepiride therapy, however, resulted in a more rapid decline in A1C levels at weeks 6, 12, and 20 vs. pioglitazone (p < 0.05). A mean A1C < or = 7% was reached faster in the glimepiride group (median, 80-90 days vs. 140-150 days [p = 0.024]). Total and LDL cholesterol were significantly higher with pioglitazone treatment than with glimepiride at endpoint (p < 0.05). Glimepiride treatment was associated with an increased risk of hypoglycemia and pioglitazone with higher rate of peripheral edema. Healthcare resource utilization was similar between groups, but total healthcare costs were significantly lower for glimepiride versus pioglitazone over the course of the study, driven largely by drug costs. The use of fasting C-peptide concentration > or = 0.27 nmol/L in the inclusion criteria was a potential limitation as it may have included those patients with an improved probability for glimepiride or pioglitazone response. In addition, a larger patient population would have provided a greater degree of data applicability. CONCLUSIONS: In patients with type 2 diabetes inadequately controlled on metformin monotherapy, add-on glimepiride or pioglitazone results in similar overall improvements in glycemic control. Compared with pioglitazone, glimepiride is associated with faster glycemic control, lower total and LDL cholesterol levels and reduced short-term healthcare costs.     

Cost effectiveness of combination therapy with pioglitazone for type 2 diabetes mellitus from a german statutory healthcare perspective

BACKGROUND: Pioglitazone has been approved in Europe for oral combination therapy for type 2 diabetes mellitus. Along with other agents of the thiazolidinedione class, it has a novel intracellular mechanism of action. Clinical trials with pioglitazone have confirmed a strong product profile in terms of control of blood glucose and lipids. However, the drug acquisition cost for pioglitazone is greater than standard medications for type 2 diabetes. Long-term data regarding the cost effectiveness of pioglitazone-based combination therapy are not available. OBJECTIVE: To evaluate, using a decision analysis model, the cost effectiveness of pioglitazone-based combination therapy compared with relevant alternative medications for the treatment of type 2 diabetes in Germany. METHODS: This study compared the clinical effects and costs of pioglitazone 30 mg added to metformin in patients who failed metformin monotherapy and pioglitazone added to a sulphonylurea in patients who failed sulphonylurea monotherapy, with the most relevant treatment alternatives. A published and validated Markov model was adapted to reflect the management of type 2 diabetes. This simulated the number of severe complications occurring and the mean life expectancy of a diabetic cohort, which was based on the overweight group of the UK Prospective Diabetes Study at year 6 of follow-up. Drug treatment costs, other costs for general management of type 2 diabetes and the costs of complications were combined to compute overall lifetime treatment costs from the perspective of the German statutory healthcare system in 2002. RESULTS: Combination therapy with pioglitazone/metformin was associated with a higher life expectancy (15.2 years) relative to sulphonylurea/metformin (14.9 years) or acarbose/metformin (14.7 years). Likewise, pioglitazone/sulphonylurea (15.5 years) was superior to metformin/sulphonylurea (14.9 years) and acarbose/sulphonylurea (14.8 years). Undiscounted incremental cost-effectiveness ratios in comparison to the next best strategy were euro20,002 per life-year gained (LYG) for pioglitazone/metformin versus sulphonylurea/metformin, and euro8707 per LYG for pioglitazone/sulphonylurea versus metformin/sulphonylurea. After discounting costs and life expectancy at 5% per year, the incremental cost-effectiveness ratio was euro47 636 per LYG for pioglitazone/metformin versus sulphonylurea/metformin, and euro19 745 per LYG for pioglitazone/sulphonylurea versus metformin/sulphonylurea. CONCLUSIONS: In this model, with its underlying assumptions and data, combination therapy with pioglitazone increased life expectancy in overweight type 2 diabetes patients at acceptable cost compared with other well established medications in Germany. These findings should be re-evaluated as soon as additional evidence becomes available from the currently ongoing long-term clinical and economic studies.     

Pioglitazone, rosiglitazone, and rosiglitazone + metformin: new drugs. Glitazone + oral antidiabetic combination: inadequately evaluated

(1) When single-agent therapy provides inadequate glycaemic control for patients with type 2 diabetes, most guidelines recommend metformin in combination with a glucose-lowering sulphonylurea as standard treatment, despite the lack of any proven impact on morbidity or mortality. Other options include switching to insulin or abandoning the target of strict glycaemic control. (2) Pioglitazone and rosiglitazone are approved for use in combination with a glucose-lowering sulphonylurea when metformin is poorly tolerated or contraindicated, and in combination with metformin in overweight patients. (3) A fixed-dose combination containing 1 or 2 mg of rosiglitazone plus 500 mg of metformin (hydrochloride) was launched onto the French market in October 2004. (4) The indication for rosiglitazone was extended to include its use as triple-agent therapy in combination with metformin and a glucose-lowering sulphonylurea. (5) No clinical trials assessing effects on mortality or morbidity have evaluated rosiglitazone or pioglitazone in combination with other oral antidiabetic drugs. (6) Several trials have compared the glucose-lowering effects of dual-agent therapy using rosiglitazone or pioglitazone plus a glucose-lowering sulphonylurea or metformin versus dual-agent therapy with metformin and a glucose-lowering sulphonylurea. (7) These clinical trials indicate that in terms of HbA1c level, dual-agent therapy based on rosiglitazone or pioglitazone is about as effective as combination therapy with metformin plus a glucose-lowering sulphonylurea. (8) The main known adverse effect of pioglitazone and rosiglitazone is water-sodium retention, which can provoke oedema and haemodilution anaemia, and can aggravate or reveal heart failure. (9) Pioglitazone has a positive effect on the lipid profile, whereas rosiglitazone increases the LDL-cholesterol level. (10) Dual-agent therapy with pioglitazone and a sulphonylurea causes more weight gain than metformin plus a sulphonylurea. (11) Several trials have assessed triple-agent regimens containing a glitazone. Three placebo-controlled double-blind trials have tested pioglitazone (one trial, nearly 300 patients) or rosiglitazone (two trials, about 1200 patients) for 12 to 26 weeks in patients whose glycaemia was poorly controlled by dual-agent therapy with a sulphonylurea plus metformin. The glycated haemoglobin level fell by 0.3% to 1.1% (in absolute values), depending on the trial and the dosage, but at a cost of the usual adverse effects such as weight gain, anaemia and oedema. Three unblinded trials have compared oral triple-agent regimens containing glitazone versus insulin plus metformin, alone or in combination with a glucose-lowering sulphonylurea; the treatment including glitazone was no more effective in terms of the glycated haemoglobin level, but was associated with an increase in adverse effects and dropouts. (12) Given the limited clinical data available in early 2005, pioglitazone and rosiglitazone have no place in the management of type 2 diabetes.     

A lifetime modelled economic evaluation comparing pioglitazone and rosiglitazone for the treatment of type 2 diabetes mellitus in the UK

INTRODUCTION: Adding pioglitazone or rosiglitazone to existing therapy are alternative treatment options for patients with type 2 diabetes mellitus who have insufficient glycaemic control while receiving the maximal tolerated dose of metformin monotherapy. Our objective was to develop a lifetime model of type 2 diabetes mellitus and its sequelae in order to compare the costs and benefits of pioglitazone versus rosiglitazone in combination with metformin. METHODS: A decision-analytic model employing a first order Monte Carlo simulation of a Markov process was constructed. The model incorporated surrogate outcome measures from a large randomised controlled trial (RCT) [n = 802] that compared the glycaemic and lipid control of pioglitazone and rosiglitazone monotherapy. These efficacy data were used with a recently validated and peer-reviewed UKPDS (UK Prospective Diabetes Study) algorithm to simulate the progression of these surrogate outcomes to final health outcomes, including quality of life (QOL) and mortality, and to calculate the risks of diabetic complications and death. The model perspective was of the UK NHS and included direct healthcare costs only (pounds, 2004/5 values). Patient outcomes measured in the model included life-expectancy (LE) and QALYs. The base-case analysis was run for 56-year-old male Caucasions with a haemoglobin A(1c) (HbA(1c)) of 7.57% and a body mass index of 33.14 kg/m(2). RESULTS: Patients treated with pioglitazone experienced a reduction in the total cholesterol to high-density lipoprotein-cholesterol (TC : HDL-C) ratio of 0.34, whereas the TC : HDL-C ratio increased by 0.65 in those receiving rosiglitazone (p < 0.001). The HbA(1c) profile was similar between the treatment groups (p = 0.13), as were other known risk factors for diabetes complications. The lifetime healthcare costs per patient estimated by the model were 9585 pounds for pioglitazone and 10,299 pounds for rosiglitazone. Patients treated with pioglitazone had a discounted LE of 8.83 years versus 8.79 years for those treated with rosiglitazone. Patients treated with pioglitazone also gained additional QALYs (6.8070 vs 6.7686). With improved health outcomes and lower costs, treatment with pioglitazone dominated rosiglitazone treatment. CONCLUSION: Evidence from the only large head-to-head RCT comparing rosiglitazone and pioglitazone suggests that more favourable changes in serum lipid profiles in patients treated with pioglitazone translate into improved health outcomes in terms of reduced morbidity and mortality and greater gains in QOL. In addition, this analysis indicates that treatment with pioglitazone is associated with lower costs than rosiglitazone. Therefore, in the UK, adjunctive pioglitazone may represent a cost-effective treatment choice for patients with type 2 diabetes who have insufficient glycaemic control while receiving the maximal tolerated dose of metformin monotherapy.