For Healthcare Professionals

Understanding the differences in TZDs

Each TZD has a distinct molecular fingerprint

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  • PPARs modify gene expression.[1-3]
  • PPAR (peroxisome proliferator-activated receptor gamma) is a regulator in:[1-3]
    • Glucose metabolism.
    • Lipid metabolism.
    • Inflammation.
  • PPAR agents modify gene expression differently.[4,5]

ACTOS and Avandia can regulate different genes[6]

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  • The effects of specific gene regulation on clinical outcomes have not been determined.
  • Not all genes regulated by PPAR agents result in clinically significant effects.

*Results from an in vitro study analyzing gene expression of TZDs with microarrays and VAMPIRE (Variance-Modeled Posterior Inference with Regional Exponentials) in 3T3-L1 murine adipocytes.

 

These unique fingerprints may result in clinical differences[1,2,7]

Change in lipids from baseline with ACTOS at
2 years†

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†Results from a 104-week, double-blind, randomized, double-dummy, multicenter, parallel-group study using ACTOS 30 or 45 mg QD monotherapy. Completer analysis, n=147. Mean change at endpoint statistically significant vs baseline, at P<0.0001.

“The TZDs either have a beneficial or neutral effect on atherogenic lipid profiles, with pioglitazone having a more beneficial effect than rosiglitazone.”[8]
— The American Diabetes Association and the European Association for the Study of Diabetes

  • A separate study found that despite similar glycemic effects, each TZD can affect lipid parameters differently.[1,7,9]
  • ACTOS was shown to:
    • Increase HDL-C.
    • Lower triglycerides.
    • Decrease LDL particle concentration.
    • Increase LDL particle size.
    • Have a neutral effect on non–HDL-C and Apo B.
    • Produce no consistent mean changes in LDL-C or Total-C.
  • In a conversion study, key lipid parameters improved after switching from Avandia plus metformin to ACTOS plus metformin.[7]

While ACTOS may confer some lipid benefits, ACTOS is not indicated to treat lipid disorders and should not be used as a substitute for lipid-lowering therapy.

The effects of these lipid changes on morbidity and mortality have not been determined.

Management of type 2 diabetes should also include nutritional counseling, weight reduction as needed, and exercise.

Please see Important Safety Information, including boxed warning for congestive heart failure, below.

References:
1. ACTOS package insert, Takeda Pharmaceuticals America, Inc.
2. Avandia package insert, GlaxoSmithKline.
3. Staels B, Fruchart JC. Therapeutic roles of peroxisome proliferator-activated receptor agonists. Diabetes. 2005;54:2460-2470.
4. Camp HS, Li O, Wise SC, et al. Differential activation of peroxisome proliferator-activated receptor- by troglitazone and rosiglitazone. Diabetes. 2000;49:539-547.
5. Tian Q, Stepaniants SB, Mao M, et al. Integrated genomic and proteomic analyses of gene expression in mammalian cells. Mol Cell Proteomics. 2004;3:960-969.
6. Hsiao A, Worrall DS, Olefsky JM, Subramaniam S. Variance-modeled posterior inference of microarray data: detecting gene-expression changes in 3T3-L1 adipocytes. Bioinformatics. 2004;20:3108-3127.
7. Data on file, Takeda Pharmaceuticals North America, Inc.
8. Nathan DM, Buse JB, Davidson MB, et al. Management of hyperglycemia in type 2 diabetes: a consensus algorithm for the initiation and adjustment of therapy. Diabetes Care. 2006;29:1963-1972.
9. Goldberg RB, Kendall DM, Deeg MA, et al, for the GLAI Study Investigators. A comparison of lipid and glycemic effects of pioglitazone and rosiglitazone in patients with type 2 diabetes and dyslipidemia. Diabetes Care. 2005;28:1547-1554.

Avandia® is a registered trademark of GlaxoSmithKline.

Boxed Warning: Congestive Heart Failure

• Thiazolidinediones (TZDs), including ACTOS, cause or exacerbate congestive heart failure (CHF) in some patients. After initiation of ACTOS and after dose increases, observe patients carefully for signs and symptoms of heart failure (including excessive rapid weight gain, dyspnea, and/or edema). If these signs and symptoms develop, the heart failure should be managed according to current standards of care. Furthermore, discontinuation or dose reduction of ACTOS must be considered.[1]
• ACTOS is not recommended in patients with symptomatic heart failure. Initiation of ACTOS in patients with established NYHA Class III or IV heart failure is contraindicated.[1]

Cardiac considerations
Like other TZDs, ACTOS can cause fluid retention when used alone or in combination with other antidiabetic agents, including insulin. Fluid retention may lead to or exacerbate CHF. ACTOS should be used with caution in patients at risk for heart failure. Patients should be monitored for symptoms of heart failure or other adverse events related to fluid retention. In clinical trials, a small number of patients with a history of previously existing cardiac disease were reported to develop CHF when treated with ACTOS in combination with insulin. Reports of CHF have been received in postmarketing experience in patients with and without previously known heart disease.[1]

Hepatic safety
Reports of hepatitis and of hepatic enzyme elevations to three or more times the upper limit of normal (ULN) have been received in postmarketing experience with pioglitazone. Very rarely, these reports have involved hepatic failure with or without fatal outcome, although causality has not been established. Liver enzymes, including serum ALT, should be evaluated in all patients at initiation of therapy with ACTOS, and periodically thereafter per the clinical judgment of the healthcare professional. If ALT >2.5X ULN at baseline or if the patient exhibits clinical evidence of active liver disease, do not initiate therapy with ACTOS.[1]

Other considerations
ACTOS may also be associated with hypoglycemia, edema, anemia, weight gain, and/or ovulation in premenopausal, anovulatory women. Adequate contraception should be recommended for premenopausal women. Macular edema has been reported in some diabetic patients receiving TZD therapy, although a causal relationship is unknown. Persons with diabetes should have routine eye exams and be instructed to immediately report any visual changes to their healthcare provider. An increased incidence of bone fracture was noted in female patients taking ACTOS. The risk of fracture should be considered in the care of patients treated with ACTOS, particularly females, and attention should be given to assessing and maintaining bone health according to current standards of care.[1]

Well-tolerated therapy
In US placebo-controlled ACTOS monotherapy clinical trials, the most common adverse events (≥5%) were upper respiratory tract infection, headache, sinusitis, myalgia, tooth disorder, aggravated diabetes mellitus, and pharyngitis.[1]

Indications and usage
ACTOS is indicated as an adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes. ACTOS is approved for use as monotherapy and in combination with sulfonylureas, metformin, or insulin when diet and exercise plus the single agent do not result in adequate glycemic control.[1] • ACTOS should not be used in patients with type 1 diabetes. Management of type 2 diabetes should also include nutritional counseling, weight reduction as needed, and exercise.[1]

The major metabolic defects in type 2 diabetes are peripheral insulin resistance in muscle and fat, decreased pancreatic insulin secretion, and increased hepatic glucose output.[2] Dyslipidemia in insulin resistance is represented by hypertriglyceridemia, decreased HDL levels, and increased small dense LDL particles.[3] Renal and gastrointestinal function are also clinical considerations when prescribing an oral agent for type 2 diabetes.[4]

Please see Complete Prescribing Information, including boxed warning for congestive heart failure, and Medication Guide.

References:
1.
ACTOS package insert, Takeda Pharmaceuticals America, Inc. 2. Schinner S, Scherbaum WA, Bornstein SR, Barthel A. Molecular mechanisms of insulin resistance. Diabet Med. 2005;22:674-682. 3. American Diabetes Association. Dyslipidemia management in adults with diabetes. Diabetes Care. 2004;27(suppl 1):S68-S71. 4. American Diabetes Association. Standards of medical care in diabetes–2008. Diabetes Care. 2008;31(suppl 1):S12-S54.