Early antiretroviral treatment (ART) -- defined as starting treatment within the first three months after being infected with HIV -- can preserve immune system functioning, reduce latent inflammation and limit the size of the viral reservoir, an expert explained in a recent webinar. Studying the effects of such treatment also aids research into a "functional" cure of HIV, meaning that people would no longer need to take antiretroviral medications, they would no longer transmit the virus and their HIV infection would not progress, said the expert, Jintanat Ananworanich, M.D., Ph.D., of the U.S. military's HIV research program.
The webinar took place on June 23. It was the fourth in a series of five educational webinars entitled "CUREiculum," organized by AVAC -- Global Advocacy for HIV Prevention.
In her talk, Ananworanich explained that some people who start ART very soon after infection are able to stop treatment after some time yet continue to control their viral load without medication. These are called "post-treatment controllers" (which is different from "elite controllers" who achieve undetectable viral loads without ever having taken antiretroviral medications.) "Long-term non-progressors," by contrast, have detectable viral loads, but their disease does not progress despite not taking ART.
A few clinical trials have included significant numbers of participants who were diagnosed with HIV and started treatment very early in their infection. One such trial was VISCONTI, in which 14 men and women who started treatment within 10 weeks of infection remained on ART for an average of three years, then stopped treatment and continue to have an undetectable viral load. Such spontaneous control of the virus is rare and may also not translate into life-long control of HIV, Ananworanich cautioned. Other such trials are the FRESH study of high-risk young women in South Africa and RV 217/ECHO, which is being conducted by the U.S. military in East Africa and Thailand. Both of these studies involve HIV testing every two weeks and immediate treatment upon a positive result, according to Ananworanich.
Such early diagnosis and treatment is difficult to achieve in adults outside research study environments, Ananworanich said. Many testing facilities do not use the fourth-generation highly sensitive HIV tests that can detect the virus within two to three weeks of infection, people do not usually get tested frequently or soon enough and medications may not be on hand for immediate treatment, she noted.
Infants are tested at birth, so they can be more easily treated during acute HIV infection. However, the window for limiting establishment of the viral reservoir may already have closed even in newborns, if they were infected in utero early in the pregnancy, Ananworanich cautioned. A current proof of concept study called IMPAACT P1115 is assessing early intensive ART in newborns to see whether viral remission can be achieved in very young children.
While people who start ART very soon after infection could be good candidates for an HIV cure trial, there are challenges. For example, early treatment participants may suffer under the misconception that early ART itself will cure them, and it may be too risky to take them off treatment since they are usually otherwise healthy, Ananworanich concluded.