Avandia – The Hits just keep on coming
“In a multivariate logistic regression model, a diagnosis of cancer was significantly associated with TZD use, even after correcting for potential confounders including other oral anti-diabetic agents (sulfonylureas and biguanides), age, glycosylated hemoglobin A1C, body mass index, cigarette smoking, high comorbidity, and number of prescription medications (odds ratio = 1.59, P = 0.04). This association was particularly strong among patients using
rosiglitazone (OR = 1.89, P = 0.02), and among women (OR = 2.07, P = 0.01).
These data suggest an association between TZD use and cancer in patients with diabetes.”
These words come from a study published in the current issue of BMC Medicine. In this study a randomly selected sample of 1,003 participants were interviewed about personal and clinical characteristics, including any history of malignancy.
The most damning aspect of the study was use of Avandia increased malignancy risk by 89%, while increased risk with Actos was not statistically significant. According to the researchers “We are not aware of a convincing explanation or previous results to support the finding in this study of an association with cancer for rosiglitazone (Avandia), but not for pioglitazone (Actos).”
Just as the original meta-analysis that started the whole Avandia came with limitations so does this particular study. According to Dr. Maria E. Ramos-Nino from the University of Vermont, Burlington, lead author of the study; “Our data do not provide strong evidence to change practice at this time. They are disturbing, to be sure, but require further investigation before clinical decisions should be changed.”
It seems with each day leading up to the FDA’s panel meeting on Avandia another study is published which indicates problems with the drug. This avalanche of study data places an increasing burden on GlaxoSmithKline (NYSE:GSK) and the FDA. As Diabetic Investor reported yesterday it’s becoming more difficult to find a scenario where Glaxo can save Avandia and may be left with no choice but to pull the drug from the market. Even if the FDA requires stronger warning language for Avandia, as many suspect, with all this data it would not be surprising if the agency also required additional studies. Under this scenario Glaxo would be between a rock and hard place. In the end the company could well decide their resources are better spent defending the company from pending litigation.
Reviewing how this whole controversy began and the events that transpired since the original meta-analysis was published Diabetic Investor sees another problem on the horizon. Has the drug approval and post-market surveillance process become corrupted? Patients and physicians want clear guidance and at least some confidence that drugs approved by the FDA will do no harm. Diabetic Investor is disturbed that the authors of these studies do not reach definitive conclusions and pass the buck by calling more even more studies. Just what are patients and physicians supposed to do while these studies are being done? Studies that will likely end up calling for even more studies.
Like it or not the reality of the situation is all drugs carry some degree of risk, there is no such thing as a risk free drug. Patients and physicians are ignorant of this fact; they just want to know all relevant information so they can make an informed choice. The complications associated with poorly controlled diabetes are severe and patients cannot wait years for a study to conclude more study is necessary. This is ludicrous.