The Centers for Disease Control and Prevention (CDC) has issued new guidelines to health care providers for the use of Truvada (tenofovir/emtricitabine) as pre-exposure prophylaxis (PrEP) for HIV, urging the therapy’s use among those at high risk of infection. The CDC states that, when taken daily as directed, PrEP can reduce the risk of HIV infection by more than 90 percent, and that poor adherence to the therapy diminishes this effect.

The CDC outlined four recommended categories of HIV-negative people for whom clinicians should consider prescribing PrEP:

•    Anyone in an ongoing sexual partnership with someone who is living with the virus.
•    A man who has had sex with men without a condom or who has been diagnosed with a sexually transmitted infection (STI) in the past six months and who is not in a mutually monogamous relationship with a partner who has recently tested HIV negative.
•    A heterosexual man or woman who does not always use condoms for sex with partners at high risk for HIV (such as injection drug users or men who have sex with men whose HIV status is unknown) and is not in a mutually monogamous relationship with a partner who has recently tested HIV negative.
•    Anyone who, within the past six months, has shared equipment when injecting illicit drugs or who has been in an injection drug treatment program.

These guidelines are narrower than those issued in January by the New York State Department of Health’s AIDS Institute. Its list of people who should be considered for PrEP include those who: engage in transactional sex (such as sex for money, drugs or housing); use stimulant drugs, such as crystal meth, that are associated with high-risk behaviors; have been diagnosed with an STI in the past year; who inject illicit drugs one or more times a day; are transgender and who share equipment to inject hormones; or who have been prescribed post-exposure prophylaxis (PEP) to prevent HIV infection for reasons outside of occupational exposure to the virus and who continue to engage in high-risk behavior or who have used PEP multiple times.

The CDC provides guidelines to clinicians on how to encourage adherence to PrEP, as well as how to promote the therapy’s use in combination with condoms and other risk-reduction methods.

The agency also stresses the importance of heeding to the U.S. Food and Drug Administration’s (FDA) guidelines to test for HIV before prescribing PrEP and then to test quarterly thereafter during the therapy’s use. This protocol is to try to prevent resistant strains of virus should someone taking PrEP contract the virus and then proceed to take only the two drugs contained in Truvada as opposed to the minimum of three for an antiretroviral cocktail strong enough to combat a chronic HIV infection.

“PrEP is a new approach to HIV prevention that requires continuing collaboration between patients and providers, as effectiveness requires adherence to daily medication and regular medical visits for monitoring, counseling and testing,” Dawn K. Smith, MD, MPH, the epidemiologist in CDC’s Division of HIV/AIDS Prevention who led the development of the guidelines, said in a release. “Individuals will have to decide with their doctor if PrEP is right for them, but for some, this may offer a much-needed strategy to help protect themselves from HIV infection.”

To read the CDC release, click here.