Case Evaluation

Avandia: Avandia Side Effects - Conclusion

Rosiglitazone is not the first PPAR agonist that has been reported to increase adverse cardiovascular events. Muraglitazar, an investigational dual PPAR-a and PPAR-. agonist, increased adverse cardiovascular events, including myocardial infarction, during phase 2 and 3 testing.28 After publication of an analysis of cardiovascular outcomes, muraglitazar was not approved by the FDA, and further development was subsequently halted by the manufacturer. Development programs for many other PPAR agonists have been terminated after evidence of toxicity emerged during preclinical studies or initial trials in humans. According to a former FDA official, more than 50 Investigational New Drug applications for novel PPARs have been filed, but no additional drugs have successfully reached the market in more than 6 years.29 In some cases, these drugs have failed because of evidence of direct myocardial toxicity in studies in animals,29 but few data on toxicity are available in the public domain because of the common industry practice of not publishing safety findings for failed products.

PPAR agonists such as rosiglitazone have very complex biologic effects, resulting from the activation or suppression of dozens of genes.30 The patterns of gene activation or suppression differ substantially among various PPAR agonists, even within closely related compounds. The biologic effects of the protein targets for most of the genes influenced by PPAR agonists remain largely unknown. Accordingly, many different and seemingly unrelated toxic effects have emerged during development of other PPAR agents.29 Some drugs have provoked multispecies, multi– organ system cancers; others have resulted in rhabdomyolysis or nephrotoxicity.29 Troglitazone was withdrawn from the market for rare, but sometimes fatal, liver toxicity. Accordingly, it must be assumed that a variety of unexpected toxic effects are possible when PPAR agonists are administered to patients.

The question as to whether the observed risks of rosiglitazone represent a "class effect" of thiazolidinediones must also be considered. Pioglitazone is a related agent also widely used to treat type 2 diabetes mellitus. However, unlike rosiglitazone, pioglitazone has been studied in a prospective, randomized trial of cardiovascular outcomes, called Prospective Pioglitazone Clinical Trial in Macrovascular Events (PROACTIVE).31 The primary end point, a broad composite that included coronary and peripheral vascular events, showed a trend toward benefit from pioglitazone (hazard ratio, 0.90; P=0.095). A secondary end point consisting of myocardial infarction, stroke, and death from any cause showed a significant effect favoring pioglitazone (hazard ratio, 0.84; P=0.027). Notably, pioglitazone appears to have more favorable effects on lipids, particularly triglycerides, than does rosiglitazone. 32

These emerging findings raise an important question about the appropriateness of the current regulatory pathways for the development of drugs to treat diabetes. The FDA considers demonstration of a sustained reduction in blood glucose levels with an acceptable safety profile adequate for approval of antidiabetic agents. However, the ultimate value of antidiabetic therapy is the reduction of the complications of diabetes, not improvement in a laboratory measure of glycemic control. Although reductions in blood glucose levels have been shown to reliably reduce microvascular complications of diabetes, the effect on macrovascular complications has proved to be unpredictable.33 After the failure of muraglitazar and the apparent increase in adverse cardiovascular outcomes with rosiglitazone, the use of blood glucose measurements as a surrogate end point in regulatory approval must be carefully reexamined.

Our study has important limitations. We pooled the results of a group of trials that were not originally intended to explore cardiovascular outcomes. Most trials did not centrally adjudicate cardiovascular outcomes, and the definitions of myocardial infarction were not available. Many of these trials were small and short-term, resulting in few adverse cardiovascular events or deaths. Accordingly, the confidence intervals for the odds ratios for myocardial infarction and death from cardiovascular causes are wide, resulting in considerable uncertainty about the magnitude of the observed hazard. Furthermore, we did not have access to original source data for any of these trials. Thus, we based the analysis on available data from publicly disclosed summaries of events. The lack of availability of source data did not allow the use of more statistically powerful time-to-event analysis. A meta analysis is always considered less convincing than a large prospective trial designed to assess the outcome of interest. Although such a dedicated trial has not been completed for rosiglitazone, the ongoing Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycaemia in Diabetes (RECORD) trial may provide useful insights.34

Despite these limitations, our data point to the urgent need for comprehensive evaluations to clarify the cardiovascular risks of rosiglitazone. The manufacturer’s public disclosure of summary results for rosiglitazone clinical trials is not sufficient to enable a robust assessment of cardiovascular risks. The manufacturer has all the source data for completed clinical trials and should make these data available to an external academic coordinating center for systematic analysis. The FDA also has access to study reports and other clinical-trial data not within the public domain. Further analyses of data available to the FDA and the manufacturer would enable a more robust assessment of the risks of this drug. Our data suggest a cardiovascular risk associated with the use of rosiglitazone. Until more precise estimates of the cardiovascular risk of this treatment can be delineated in patients with diabetes, patients and providers should carefully consider the potential risks of rosiglitazone in the treatment of type 2 diabetes.

Dr. Nissen reports receiving research support to perform clinical trials through the Cleveland Clinic Cardiovascular Coordinating Center from Pfizer, AstraZeneca, Daiichi Sankyo, Roche,Takeda,Sanofi-Aventis, and Eli Lilly. Dr. Nissen consults for many pharmaceutical companies but requires them to donate all honoraria or consulting fees directly to charity so that he receives neither income nor a tax deduction. No other potential conflict of interest relevant to this article was reported.

We thank Craig Balog for statistical programming support.

REFERENCES

1. Vamecq J, Latruffe N. Medical significance of peroxisome proliferator-activated receptors. Lancet 1999;354:141-8.

2. Campbell IW. The clinical significance of PPAR gamma agonism. Curr Mol Med 2005;5:349-63.

3. Center for Drug Evaluation and Research. Approval package: Avandia (rosiglitazone maleate) tablets. Company: SmithKline Beecham Pharmaceuticals. Application no. 21-071. Approval date: 5/25/1999. (Accessed May 15, 2007, at http://www.fda.gov/cder/foi/nda/99/21071_ Avandia.htm.)

4. American Diabetes Association. Complications of diabetes in the United States. (Accessed May 15, 2007, at http://www. diabetes.org/diabetes-statistics/ complications.jsp.)

5. GlaxoSmithKline. Rosiglitazone studies. (Accessed May 15, 2007, at http://ctr. gsk.co.uk/Summary/rosiglitazone/ studylist.asp.)

6. Center for Drug Evaluation and Research. Medical review(s). Application number: 021071. (Accessed May 15, 2007, at http://www.fda.gov/cder/foi/nda/99/ 21071_Avandia_medr.pdf.)

7. Lebovitz HE, Dole JF, Patwardhan R, Rappaport EB, Freed MI. Rosiglitazone monotherapy is effective in patients with type 2 diabetes. J Clin Endocrinol Metab 2001;86:280-8. [Errata, J Clin Endocrinol Metab 2001;86:1659, 2002;2:iv.]

8. Phillips LS, Grunberger G, Miller E, et al. Once-and twice-daily dosing with rosiglitazone improves glycemic control in patients with type 2 diabetes. Diabetes Care 2001;24:308-15. [Erratum, Diabetes 2001;24:973.]

9. Jones TA, Sautter M, Van Gaal LF, Jones NP. Addition of rosiglitazone to metformin is most effective in obese, insulin- resistant patients with type 2 diabetes. Diabetes Obes Metab 2003;5:163-70.

10. Fonseca V, Rosenstock J, Patwardhan R, Salzman A. Effect of metformin and rosiglitazone combination therapy in patients with type 2 diabetes mellitus: a randomized controlled trial. JAMA 2000;283: 1695-702. [Erratum, JAMA 2000;284: 1384.]

11. Weissman P, Goldstein BJ, Rosenstock J, et al. Effects of rosiglitazone added to submaximal doses of metformin compared with dose escalation of metformin in type 2 diabetes: the EMPIRE Study. Curr Med Res Opin 2005;21:2029-35.

12. Wolffenbuttel BH, Gomis R, Squatrito S, Jones NP, Patwardhan RN. Addition of low-dose rosiglitazone to sulphonylurea therapy improves glycaemic control in Type 2 diabetic patients. Diabet Med 2000;17:40-7.

13. St John Sutton M, Rendell M, Dandona P, et al. A comparison of the effects of rosiglitazone and glyburide on cardiovascular function and glycemic control in patients with type 2 diabetes. Diabetes Care 2002;25:2058-64.

14. Raskin P, Rendell M, Riddle MC, et al. A randomized trial of rosiglitazone therapy in patients with inadequately controlled insulin-treated type 2 diabetes. Diabetes Care 2001;24:1226-32.

15. Vongthavaravat V, Wajchenberg BL, Waitman JN, et al. An international study of the effects of rosiglitazone plus sulphonylurea in patients with type 2 diabetes. Curr Med Res Opin 2002;18:456-61.

16. Baksi A, James RE, Zhou B, Nolan JJ. Comparison of uptitration of gliclazide with the addition of rosiglitazone to gliclazide in patients with type 2 diabetes inadequately controlled on half-maximal doses of a sulphonylurea. Acta Diabetol 2004;41:63-9.

17. Barnett AH, Grant PJ, Hitman GA, et al. Rosiglitazone in Type 2 diabetes mellitus: an evaluation in British Indo-Asian patients. Diabet Med 2003;20:387-93.

18. Kerenyi Z, Samer H, James R, Yan Y, Stewart M. Combination therapy with rosiglitazone and glibenclamide compared with upward titration of glibenclamide alone in patients with type 2 diabetes mellitus. Diabetes Res Clin Pract 2004;63:213-23.

19. Zhu XX, Pan CY, Li GW, et al. Addition of rosiglitazone to existing sulfonylurea treatment in Chinese patients with type 2 diabetes and exposure to hepatitis B or C. Diabetes Technol Ther 2003;5:33-42.

20. The DREAM (Diabetes Reduction Assessment with ramipril and rosiglitazone Medication) Investigators. Effect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired fasting glucose: a randomised controlled trial. Lancet 2006;368:1096105. [Erratum, Lancet 2006;368:1770.]

21. Kahn SE, Haffner SM, Heise MA, et al. Glycemic durability of rosiglitazone, metformin, or glyburide monotherapy. N Engl J Med 2006;355:2427-43. [Erratum, N Engl J Med 2007;356:1387-8.]

22. Bradburn MJ, Deeks JJ, Berlin JA, Localio AR. Much ado about nothing: a comparison of the performance of meta-analytical methods with rare events. Stat Med 2007;26:53-77.

23. Sweeting MJ, Sutton AJ, Lambert PC. What to add to nothing? Use and avoidance of continuity corrections in metaanalysis of sparse data. Stat Med 2004;23: 1351-75. [Erratum, Stat Med 2006;25:2700.]

24. Sutton A, Cooper N, Lambert P, Jones D, Abrams K, Sweeting M. Meta-analysis of rare and adverse event data. Pharmacoeconomics Outcomes Res 2002;2:367.

25. Avandia (rosiglitazone maleate) tablets: prescribing information. Research Triangle Park, NC: GlaxoSmithKline, 2007 (package insert). (Accessed May 15, 2007, at http://www.fda.gov/cder/foi/label/ 2007/021071s023lbl.pdf.)

26. Nesto RW, Bell D, Bonow RO, et al. Thiazolidinedione use, fluid retention, and congestive heart failure: a consensus statement from the American Heart Association and American Diabetes Association: October 7, 2003. Circulation 2003; 108:2941-8.

27. Lygate CA, Hulbert K, Monfared M, Cole MA, Clarke K, Neubauer S. The PPARgamma-activator rosiglitazone does not alter remodeling but increases mortality in rats post-myocardial infarction. Cardiovasc Res 2003;58:632-7.

28. Nissen SE, Wolski K, Topol EJ. Effect Rosiglitazone and Cardiovascular Outcomes of muraglitazar on death and major adverse cardiovascular events in patients with type 2 diabetes mellitus. JAMA 2005; 294:2581-6.

29. El-Hage J. Peroxisome proliferatoractivated receptor (PPAR) agonists: preclinical and clinical cardiac safety considerations. Rockville, MD: Center for Drug Evaluation and Research, 2006. (Accessed May 15, 2007, at http://www.fda.gov/cder/ present/DIA2006/El-Hage_CardiacSafety. ppt.)

30. Lemay DG, Hwang DH. Genome-wide identification of peroxisome proliferator response elements using integrated computational genomics. J Lipid Res 2006; 47:1583-7.

31. Dormandy JA, Charbonnel B, Eckland DJ, et al. Secondary prevention of macro- vascular events in patients with type 2 diabetes in the PROactive Study (PROspective pioglitAzone Clinical Trial In macroVascular Events): a randomised controlled trial. Lancet 2005;366:1279-89.

32. Goldberg RB, Kendall DM, Deeg MA, et al. A comparison of lipid and glycemic effects of pioglitazone and rosiglitazone in patients with type 2 diabetes and dyslipidemia. Diabetes Care 2005;28:1547 54.

33. Riveline JP, Danchin N, Ledru F, Var- roud-Vial M, Charpentier G. Sulfonylureas and cardiovascular effects: from experimental data to clinical use: available data in humans and clinical applications. Diabetes Metab 2003;29:207-22.

34. Home PD, Pocock SJ, Beck-Nielsen H, et al. Rosiglitazone Evaluated for Cardiac Outcomes and Regulation of Glycaemia in Diabetes (RECORD): study design and protocol. Diabetologia 2005;48:1726-35.

Dangerous Drug Case Evaluation

* First Name:
* Last Name:
* Zipcode:
* E-Mail:
* Phone:
Okay to call you at this number?
Yes No
Enter any relevant background information or case specifics so that we can best understand your situation:
To Prevent Automated Submissions, Enter the 4 Digit Number Shown Below
(OR YOU MAY CALL US DIRECTLY AT 888-375-7600)
9682

Dangerous Drug Links