FDA Warns of Possible MI Risk Associated with Two HIV Drugs

By Michael Smit
ROCKVILLE, Md., March 27 -- Two HIV drugs may increase the risk of heart attacks, the FDA cautioned today.
In an alert characterized as an early communication about recent findings of the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study, and the agency said data collected through Feb. 1, 2007 appeared to show an increased risk of MI associated recent use of abacavir (Ziagen) or didanosine (Videx).
The study found:
The excess risk of heart attack in patients taking at least some nucleoside reverse transcriptase inhibitors -- the class including the two drugs -- appears to be greater in patients with other risk factors for heart disease.
Some analyses found the risk of heart attack rose by 49% in patients taking didanosine and 90% in patients taking abacavir.
The risk did not appear to increase over time and appeared to be reversible after abacavir or didanosine was stopped.
But the agency said data from the D:A:D study -- an observational study of 33,347 HIV patients -- remains "incomplete."
In particular, the researchers did not evaluate the risk of heart attack when patients take tenofovir (Viread) or emtricitabine (Emtriva), two other drugs in the same class as abacavir and didanosine.
The agency also said the makers of the two drugs -- GlaxoSmithKline and Bristol-Myers Squibb -- had analyzed their own databases and found no indication of an increased risk.
Both results are "inconclusive," the agency said.
Nonetheless, the agency said, if the findings hold up, it may require revised labeling for the products. In the meantime, clinicians should "evaluate the potential risks and benefits" of each anti-HIV drug their patients are taking, the agency said.