Early AIDS Drug Use Could Reduce Sexual Transmission By 96%

HIV-positive people with healthy immune systems, who started taking oral antiretroviral medicines early in their infection reduced the risk of transmitting the virus to their sexual partners by 96%, according to new data by the National Institute of Allergy and Infectious Diseases released Thursday.

“Previous data about the potential value of antiretrovirals in making HIV-infected individuals less infectious to their sexual partners came largely from observational and epidemiological studies,” NIAID Director Anthony S. Fauci, M.D., said in a statement Thursday. “This new finding convincingly demonstrates that treating the infected individual—and doing so sooner rather than later—can have a major impact on reducing HIV transmission.”

The study, monitoring 1,762 couples, began in April 2005 by Myron Cohen, M.D., director of the Institute for Global Health and Infectious Diseases at the University of North Carolina at Chapel Hill. Ninety-seven percent of those couples participating in the international study were heterosexual.

Throughout the study, the couples received counseling on safe sex practices, free condoms, STI treatment, regular HIV testing, and frequent monitoring, as well as treatment for any HIV-related complications.

The clinical trial was supposed to end in 2015, but the NIAID released its findings four years early, after an interim evaluation of the data showed that it was clear that antiretroviral use among HIV-positive people with healthy immune systems reduced the rate of transmission to their partners by 96%.

The 11 HIV drugs that were used in various combinations included the following:

atazanavir (300 mg once daily)
didanosine (400 mg once daily)
efavirenz (600 mg once daily)
emtricitabine/tenofovir disoproxil fumarate (200 mg emtricitabine/300 mg tenofovir disoproxil fumarate once daily)
lamivudine (300 mg once daily)
lopinavir/ritonavir 800/200 mg once daily (QD) or lopinavir/ritonavir 400/100 mg twice daily (BID)
nevirapine (200 mg taken once daily for 14 days followed by 200 mg taken twice daily)
ritonavir (100 mg once daily, used only to boost atazanavir)
stavudine (weight-dependent dosage)
tenofovir disoproxil fumarate (300 mg once daily)
zidovudine/lamivudine (150 mg lamivudine/300 mg zidovudine taken orally twice daily)

The drugs used in the study were provided by Abbott Laboratories, Boehringer Ingelheim Pharmaceuticals, Inc., Bristol-Myers Squibb, Gilead Sciences, GlaxoSmithKline/Viiv Healthcare and Merck & Co., Inc. Read the full findings of the report, as announced by the NIAID.