Studie: geen verschil in risico tussen rosiglitazone en pioglitazone

Study: No difference in risks between GlaxoSmithKline's Avandia, Takeda's Actos
 

Research published Tuesday in Circulation: Cardiovascular Quality and Outcomes identified no significant difference in the risk of death or cardiovascular events among patients taking GlaxoSmithKline's Avandia (rosiglitazone) or Takeda's Actos (pioglitazone). In this analysis, approximately 4 percent of patients taking either drug suffered a heart attack, heart failure, both or died over a 33-month period.

WellPoint researchers studied 36 628 patients who had submitted insurance claims to the company for either of the drugs between 2001 and 2005. After adjusting the data, they compared the incidence of heart attack, heart failure and death for an average 14 months of treatment and 19 months of post-treatment follow-up.

Of the 28 938 patients who were propensity-score matched, 602 patients taking Avandia experienced a heart attack, heart failure, both, or died across the study period, compared to 599 patients taking Actos. The researchers noted that these figures were not considered significantly different between the two groups, and individual specific adverse event rates were also similar between the treatment regimens.

Commenting on the data, study contributor Mark Cziraky said "within the commercially insured population that we assessed, we did not see a difference between the two agents."

Acknowledging previous studies in Medicare beneficiaries that identified an increased risk of heart failure, stroke and death among patients taking Avandia, Cziraky noted that the results could differ because the average age of patients in the most recent study was 54, whereas patients treated under Medicare are typically over age 65. Moreover, the latest study was based on claims data from 2001 to 2005, before any health warnings related to the drug had emerged, whereas the other study reviewed data from 2006 and 2009, when physicians may have been more selective in choosing patients to receive the drug.

In July, FDA panel members voted 20-12 to keep Avandia on the market. At the same meeting, panellists voted 18 to 6 in support of a question that asked whether clinical data were sufficient to raise "significant safety" concerns regarding Avandia relative to Actos, and recommended continuation of the TIDE trial, which compares the two drugs.

In the last fiscal year, GlaxoSmithKline recorded $1.1 billion in sales of Avandia, while Takeda reported that Actos generated sales of 384.7 billion yen ($4.6 billion).