96% reduction in HIV transmission seen with early oral ART

Conclusion of a global study conducted by HIV Prevention Trials Network at 13 sites across Africa, Asia and the Americas

Men and women infected with HIV reduce the risk of transmitting the virus to their sexual partners through early initiation of oral anti retro-viral therapy (ART), a multi-centric global study has concluded. The risk reduced by as much as 96 per cent.

The study, HPTN 052, was conducted by HIV Prevention Trials Network (HPTN) at 13 sites across Africa, Asia and the Americas. It was designed to study the effect of immediate versus delayed use of ART in transmitting the virus from infected to uninfected sexual partners.

It also sought to examine whether early ART consumption would have a benefit for the HIV-infected individual as well. In India, two study sites were chosen, YRGCARE Medical Centre, Voluntary Health Services, Chennai, and National AIDS Research Institute (NARI), Pune.

N. Kumarasamy, Chief Medical Officer, YRGCARE, and Principal Investigator for the Chennai site, told

The Hindu that with the sexual route transmission of the virus over 90 per cent in India, the study had substantive implications for the country. The landmark trial had proved conclusively that ART must be initiated early in Indian HIV-infected person for reducing infections at the community level.

“Excellent news”

Findings from the study, the first randomised clinical trial to demonstrate that using ART early will reduce risk of transmission of infection, were reviewed by an independent Data and Safety Monitoring Board (DSMB).

“This is excellent news,” said Myron Cohen, HPTN 052 Principal Investigator, and Associate Vice Chancellor for Global Health and Director of the Institute of Global Health and Infectious Diseases at the University of North Carolina at Chapel Hill.

The Study

HPTN 052 began in April 2005, and enrolled 1,763 HIV sero-discordant couples (couples where one member is HIV-infected and the other is HIV-uninfected), the vast majority of whom (97 per cent) were heterosexual. In Pune, 180 such couples were chosen, and in Chennai, the largest number was recruited – 250 couples.

The HIV-infected person was required to have a CD4 cell count between 350-550 per cubic millimeter (cells/mm3) on enrolment and, therefore, did not require HIV treatment for his or her own health. The couples were randomly allotted to two groups: In one group, the HIV-infected person immediately began taking ART (immediate ART) and in the other, ART was begun only when the CD4 cell count fell below 250 cells/mm{+3} or on onset of an AIDS-related illness (delayed ART).

Throughout the study, both groups received HIV-related care that included counselling on safe sex practices, free condoms, treatment for sexually transmitted infections, regular HIV testing, and frequent evaluation and treatment for any complications related to HIV infection.

Results

Among the 877 couples in the delayed ART group, 27 HIV transmissions occurred. This was in contrast to only one transmission that occurred in the immediate ART group. This difference was highly statistically significant.

The viruses transmitted in all these 28 cases the source of infection as the partner was confirmed through genetic analysis. Significant benefits were noticed even for the infected partner (see graphic). All study participants will continue to be followed up for at least one more year.

Dr. Kumaraswamy said that the WHO is expected to review the study results and come out with a recommendation for early ART usage. Since bulk of the ART is dispensed through the public health system, a change in policy is necessary to start treatment earlier. In this light, the results of the study have also been shared with the National AIDS Control Organisation in Delhi.