ART prevented HIV transmission in serodiscordant couples

Providing ART to the HIV-positive partner in a serodiscordant couple reduced the rate of HIV transmission to the uninfected partner, new study results published in The Lancet have shown.

Researchers from China examined data from more than 38,000 serodiscordant couples. The data were input into national HIV epidemiology and treatment databases from 2003 to 2011. The couples were followed for up to 9 years.

Among the couples, 24,057 had received ART and 14,805 had not. The rate of HIV transmission to the uninfected partner was significantly lower in the group that did not receive treatment. In the 101,295 person-years of follow-up for the seronegative partners, the rates of infection were 2.6 per 100 person-years among the treatment-naive group and 1.3 per 100 person-years in the group that received treatment.

This translated to a 26% relative reduction in HIV transmission in those who received treatment (HR=0.74; 95% CI, 0.65-0.84).

However, the researchers also found that the protective effect of ART lasted for only 1 year. After 1 year, the transmission rates were comparable between the groups. In addition, the treatment as prevention was not effective when the HIV-positive partner was injecting drugs or had high CD4 counts.

“These results substantiate the previous evidence from smaller observational studies and one randomized clinical trial that the treatment-as-prevention approach is a feasible public health strategy on a national scale and in a developing country context,” Yiming Shao, MD, of the State Key Laboratory for Infectious Disease Prevention and Control and National Center for AIDS/STD Control and Prevention, Chinese Center for Disease Control and Prevention in Beijing, said in a press release. “The durability and generalizability of such protection, however, should take account of the patient status.”

In an accompanying editorial, Sten Vermund, MD, of Vanderbilt University, said the results are encouraging, but further insights must rely on research that is currently in progress.

“Can community, regional, national and international expertise and resources be mobilized to offer testing to all at-risk people at least yearly, link all infected people to care and offer ART to a much higher proportion of infected people that receive it at present, alongside expanded combination prevention activities?” he wrote. “Answers to these questions depend on rigorous research into implementation and program deployment, so that we can succeed in bringing programs to scale.”

For more information:

Jia Z. Lancet. 2012;doi:10.1016/S0140-6736(12)61898-4.

Vermund S. 2012;doi:10.1016/S0140-6736(12)62005-4.

Disclosure: Shao and Vermund report no relevant financial disclosures.