Drug News
Some HIV drugs raise risk of heart attack
By Sue Mueller
Apr 2, 2008 - 10:14:28 AM

WEDNESDAY April 2, 2008 (Foodconsumer.org) -- Two common HIV drugs, abacavir and didanosine, seem to increase the risk of heart attacks, according to a new study released Wednesday in the online edition of The Lancet.

In response, the U.S. Food and Drug Administration last week it was now reviewing the safety of both drugs, healthday.com reported.

Patients with HIV often take a combination of medications including a protease inhibitor and a nucleoside reverse transcriptase inhibitor such as abacavir or didanosine.

The study found in people with underlying risk for heart attack, using either abacavir or didanosine will increase the risk by 38 percent although those who did not have underlying risk for heart attack will have a smaller increase in the risk.

In the study, Dr. Jens D. Lundgren of the University of Copenhagen in Denmark and colleagues looked at data on 33,347 HIV patients and found the connection between HIV medications and heart attack.

They found commonly used nucleoside reverse transcriptase inhibitors such as  zidovudine, stavudine or lamivudine were not associated with increased risk for heart attack.

But abacavir and didanosine, two other nucleoside reverse transcriptase inhibitors, were associated with an increased rate of heart attack, the researchers found.

Those who took abacavir were twice as likely to experience heart attack as those who did not take the drug.  For those who took didanosine, the risk was increased by 50 percent.

It took about six months to eliminate the increased risk of heart attack after the patients who stopped using these drugs, the researchers said.

Lundgren recommended those who have underlying cardiovascular risk should consider using safer alternatives.

GlaxoSmithKline, the maker of abacavir, claimed in a letter published in the same issue of the journal that the company analyzed 54 studies and found no such association between the risk of heart attack and the drug.

Didanosine is made by Bristol-Myers Squibb.

The FDA said that a safety review of both drugs was underway.

"FDA continues to evaluate the overall risks and benefits of abacavir and didanosine. This evaluation may result in the need to revise labeling for the products," the agency was cited as saying in a statement.

"Until this evaluation is complete, health-care providers should evaluate the potential risks and benefits of each HIV-1 antiretroviral drug their patients are taking, including abacavir and didanosine," the FDA said.