When Prevention Fails, Immediate Drug Therapy Can Help


With safer sex fatigue, an epidemic of crystal methamphetamine use and numerous other factors likely contributing to rising HIV diagnoses among gay men, new prevention options to help uninfected individuals stay negative are urgently needed.

New national guidelines, issued this month, on the use of antiretroviral drugs to prevent infection after exposure to HIV may provide gay men across the country with an important safety net to prevent HIV infection.

This prevention alternative, called non-occupational post-exposure prophylaxis (NPEP), involves taking a combination of three antiretroviral drugs following high-risk exposure to HIV through sexual intercourse, sexual assault or injection drug use.

When treatment is started quickly and continued for 28 days, NPEP may keep HIV infection from taking hold in the body.

The precedent for using antiretroviral drugs to prevent HIV is well established.

Post-exposure prophylaxis has been recommended since 1996 to reduce the risk of HIV infection for health care workers exposed to HIV on the job—for example through a needle stick. In observational studies, post-exposure prophylaxis has been associated with an 80 percent reduction in infection risk in the occupational setting.

Since 1996, new data from human and animal studies, including encouraging results from case studies and registries of people using NPEP in other countries, have provided the necessary evidence to support its use in certain non-occupational settings and circumstances here in the U.S.

While NPEP can reduce the chances of infection in people who have been exposed, it is not a quick

Individuals who take NPEP must adhere to a daily regimen of several drugs for a full four weeks, often with unpleasant, though usually temporary, side effects. This intervention should be regarded as a last resort, for use on those rare occasions when primary HIV prevention methods—abstinence, mutual monogamy with an uninfected partner, condom use or use of sterile needles and syringes to inject drugs—are not used or do not work.

Gay men most likely to benefit from NPEP are those who usually take precautions, such as using condoms, but who occasionally lapse in using protection or who experience a condom break during sex, particularly if they know their partner is HIV-positive.

For NPEP to prevent infection, gay men and their health care providers must use it correctly. Keep the following in mind:

NPEP must be started immediately. If you think you’ve been exposed to HIV, seek care right away. NPEP must be started within 72 hours of exposure—but preferably as soon as possible—and continued for 28 days. Assuming that adherence is complete, the sooner you get antiretroviral therapy, the better your chances of avoiding HIV infection.

Knowing your partner’s HIV status is key. NPEP is recommended only when the person you had sex with is HIV-positive. But even if you’ve been exposed to someone whose status you don’t know, you should still seek care immediately. You and your doctor can decide whether NPEP is appropriate—given the circumstances of the exposure.

NPEP is not for everybody. You shouldn’t take it if your HIV risk is low or if you seek care more than 72 hours after exposure. In general, men who are frequently or repeatedly exposed to HIV because of unsafe behaviors would require sequential or near-continuous courses of NPEP, which is not recommended. Men at persistent, ongoing risk for HIV should instead be referred to intensive risk-reduction interventions which can help them stay HIV-free.

NPEP is not a replacement for staying safe. NPEP is not a substitute for abstinence, mutual monogamy with an uninfected partner, consistent condom use or other behaviors that can eliminate or reduce your exposure to HIV in the first place. Providers and patients need to work together to identify HIV risk, work out plans to change behaviors and access appropriate counseling and services.

In the third decade of the AIDS epidemic, we know that sustaining HIV prevention over the long run requires a combination of approaches—abstinence, mutual monogamy with an uninfected partner, correct and consistent condom use, expanded access to voluntary HIV counseling and testing, risk-reduction counseling for people both HIV-negative and positive and treatment of sexually transmitted infections, which can increase the risk of HIV transmissi

NPEP is yet another factor in this life-saving equation. Used correctly and responsibly, NPEP has the potential to become an important strategy in gay men’s ongoing struggle to remain HIV-free.

Dr. Ronald O. Valdiserri is deputy director of the National Center for HIV, STD, and TB Prevention at the Centers for Disease Control and Prevention (CDC), where he has worked for the past 16 years. Prior to his work at the CDC, Valdiserri was a faculty member at the University of Pittsburgh Schools of Medicine and Public Health.