Treatment as prevention

Turning the tide in the AIDS epidemic

by Julie Patterson

We have reached a turning point in the AIDS epidemic.

In August, a milestone study showed that treating HIV patients with AIDS drugs makes them remarkably less infectious. Not only do AIDS drugs save lives, they are also some of the most effective tools for HIV prevention.

This randomized multinational trial of heterosexual couples where one partner had HIV and the other didn't--called HIV Prevention Trials Network 052--confirms a growing body of research and has inspired a new urgency for treatment of HIV. AIDS activists call this "treatment as prevention."

About half of the couples in the trial were randomly assigned so that the infected partner went on antiretroviral drugs right away. In the other couples, the infected partner waited to start treatment until later in the course of the disease, a standard practice in many countries. All participants were counseled on how to protect against HIV transmission and were given free condoms and other prevention services.

Comparing the two rates of infection, HIV-positive partners taking antiretroviral drugs were 96% less likely to pass on the virus.

Antiretroviral drugs don't cure AIDS, but merely keep it in check. So the pills must be taken every day for life. Still, treatment as prevention has a financial advantage: it is a secondary benefit to the primary purpose of improving an HIV-positive individual?s health, quality of life, and lifespan.

Patients on antiretroviral medication are less infectious because the drugs sharply suppress the amount of HIV in the body, meaning people on treatment have less virus to transmit.

The hopeful results come 30 years after the disease was first identified in the U.S. Now, a combination of new and emerging HIV prevention methods has convinced many leading AIDS experts that they can dramatically reduce new infections.

"Although it is still important to develop an HIV vaccine," said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, "we have significant tools already at our disposal that can make a major impact on the trajectory of this epidemic."

?Treatment as prevention? is an umbrella term describing various HIV prevention methods where the same antiretroviral drugs that are used in treatment of HIV are instead used to reduce the risk of passing HIV to others. Many people are familiar with this AIDS-drugs-as-prevention strategy?s success in preventing mother-to-child transmission of HIV by providing these drugs to pregnant women who are HIV-positive.

In addition, HIV-negative people may also use antiretrovirals for prevention. Last year, a placebo-controlled study showed that a vaginal gel containing the AIDS drug tenofovir reduced the chance an HIV-negative woman would contract HIV by 39%. Among women who used it consistently, the gel more than halved the chance they would get infected. Further research is needed to approve a gel for general use. But work has already begun on more convenient products, such as vaginal rings that would dispense the virus-blocking drug for a month or more.

Also in this past year, several studies showed significant reductions in HIV transmission when HIV-negative people took AIDS drugs to protect themselves against HIV--reductions ranging from 44% to 73%. This concept, known as pre-exposure prophylaxis or PrEP, is based on the principle that, if medication is in the bloodstream when someone is exposed to HIV, the virus will not be able to establish itself, and this will prevent the person from becoming HIV infected.

Clearly there is no magic bullet; it is the use of these emerging HIV prevention methods in combination--added to behavior change methods such as condom promotion and limiting one's sexual partners?that could finally end the epidemic.?

Treatment as prevention has been around for a long time, but only in the last year has the evidence convinced a critical mass of AIDS scientists that it can play a major role in the combination approach to HIV prevention.

In the U.S., the National HIV/AIDS Strategy has been a significant step in the right direction, but it is not enough to counter the current, economy-driven lack of access to HIV care and treatment. Over a third of those living with HIV are not in AIDS care, even after being diagnosed.

Nearly 7,000 people in 12 states cannot afford to pay for AIDS medications and are now on waiting lists for help.? While most of these are temporarily receiving medications through ad-hoc measures, these may fail and leave people without life-saving medications. In Ohio, our HIV Drug Assistance Program waiting list has recently been cleared, but activists fear it may return after the current fiscal year ends in March 2012.?

It is time to pay attention to the science, translate it into real world HIV-prevention as part of a combination approach, and end the AIDS crisis. It starts with ensuring that our communities have what they need.? Let?s not wait.

Julie Patterson is director of capacity building at the AIDS Taskforce of Greater Cleveland.