New federal guidelines for the use of antiretroviral drugs to prevent HIV infection

Jan 20 2005

The Centers for Disease Control and Prevention (CDC) today announced new federal guidelines for the use of antiretroviral drugs to prevent HIV infection after exposure to HIV through sexual intercourse, sexual assault, injection drug use, or accidents.

“Using antiretroviral drugs after exposure is an important safety net to prevent HIV infection in certain cases," said Ronald O. Valdiserri, MD, MPH, deputy director of CDC’s National Center for HIV, STD and TB Prevention. "But the drugs are not a substitute for abstinence, mutual monogamy, or consistent and correct condom use, and should not be viewed as a quick fix."

The new guidelines recommend use of the approach, called non-occupational post-exposure prophylaxis (NPEP), only for patients who seek treatment no more than 72 hours after a high-risk exposure with a person known to be HIV-infected. Treatment should be initiated as soon as possible after exposure and continued for 28 days.

The new guidelines update HHS guidance issued in 1998, at which time data were not sufficient to recommend for or against the NPEP approach. Since then, new data from human and animal studies, case reports, and documentation of the approach’s use in several countries, including the United States, have provided evidence to support its use.

The guidance includes specific recommendations for physicians when making decisions about use of the approach. When potentially exposed persons seek care within 72 hours of exposure but don’t know the HIV status of the person who was the possible source, the guidance encourages clinicians to evaluate the risks and benefits on a case-by-case basis. When a person seeks care more than 72 hours after exposure or when HIV exposure risk is low, NPEP is not recommended. Use of the drugs is also not recommended for people whose behaviors result in frequent, recurrent exposures to HIV.

The potential benefits of using antiretroviral drugs for NPEP also must be weighed against the patient’s individual circumstances and the potential risks of the medication, including the possibility of serious side effects and ability to follow a daily regimen of taking several drugs. People who are frequently at risk of exposure to HIV, such as those who have HIV-infected sex partners and rarely use condoms, or injection drug users who often share equipment, would benefit more from intensive risk-reduction interventions than from NPEP.

Post-exposure prophylaxis has been recommended for health workers exposed to HIV since 1996 and in observational studies has been associated with an 80 percent reduction in the risk of infection. Antiretroviral regimens (ARVs) given to HIV-infected women around the time of labor have also been shown to cut the risk of mother-to-child transmission by about 50 percent.

Any three-drug combination of antiretroviral medications recommended by the U.S. Department of Health and Human Services may be used as NPEP, except those containing nevirapine. When used under conditions similar to the NPEP approach, nevirapine has been associated with severe reactions and liver damage. Women who are pregnant or of childbearing age should not receive regimens containing the drug efavirenz, which may increase the risk of birth defects.

The guidelines, developed by CDC, the Food and Drug Administration, the Health Resources and Services Administration, and the National Institutes of Health, dated January 21, 2005, are available at www.cdc.gov/mmwr/mmwr_rr.html.