In 2016, the Preventive Access Campaign launched the Undetectable = Untransmittable (U = U) initiative to end the HIV/AIDs pandemic and the stigma of HIV. U = U establishes that people with HIV whose virus is durably suppressed to the point of undetectable with antiretroviral therapy (ART) will not transmit the virus to their HIV-negative partner during condomless sex. Can this message be trusted?
In a new JAMA commentary, officials from the NIH’s National Institute of Allery and Infectious Diseases (NIAID) validate the U = U message as a scientifically sound concept.
To come to this conclusion, NIAID officials summarized results from large clinical trials and cohort studies, which have been accumulating for over a decade. The trials cited include:
The landmark HPTN 052 clinical trial, which provided the first evidence. Comparing the effect of early and delayed ART in the partner with HIV among 1763 HIV discordant couples, the study found a 96.4 percent reduction in HIV transmission in the early ART group. Of the couples, 98 percent were heterosexual.
The PARTNER 1 study, which determined the risk of HIV transmission from condomless intercourse in 1166 HIV discordant couples, with the HIV-infected partner receiving ART achieving and maintaining viral suppression. The study found no HIV transmissions after 58,000 condomless sexual acts.
A similar finding was presented in the PARTNER 2 study, which evaluated HIV transmission among men seeking sex with men (MSM), with the uninfected partner not receiving preexposure or postexposure prophylaxis. After 77,000 condomless sex acts, no cases of HIV were transmitted if the man with HIV had achieved viral suppression.
The Opposites Attract study, which involved 343 HIV-discordant MSM in Thailand, Brazil and Australia. There were no linked HIV transmissions during the time the partner with HIV had an undetectable viral load after 16,800 condomless sex acts.
Overall, the researchers maintain that the U = U prevention message incentivizes patients with HIV to seek and adhere to ART, which can ultimately end the HIV/AIDS pandemic. “The U = U concept also bridges the best of biomedical science with current concepts in behavioral and social science by removing the sense of fear and guilt that a person may be harming someone else, as well as the feeling of self-imposed and external stigma that many people with HIV experience,” the authors wrote.
They emphasize, however, that maintaining an undetectable viral load is essential. Undetectable is achieved when plasma HIV-1 RNA levels reach <200 copies/mL. In patients with HIV who are part of a discordant couple, it’s vital that:
- The infected partner take his/her ART medication as prescribed.
- The couple wait six months before having condomless sex. It can take up to six months of continuance ART to achieve an undetectable viral load.
- Viral load is checked frequently. Guidelines from the Department of Health and Human Services recommend viral load testing every three to four months after undetectable immunologic status is achieved. After two years of an undetectable status, testing can be extended to every six months.
Patients must also understand that if they stop ART, viral load can rebound in just two to three weeks. HIV may become detectable and therefore, transmittable. Infected patients who stop ART for whatever reason should avoid condomless sex.