VANCOUVER, B.C. and DURHAM, N.C. - A Phase III, individually randomized trial has found conditional cash transfers for school attendance did not reduce the risk of HIV among high-school aged women in South Africa, investigators from the HIV Prevention Trials Network (HPTN) reported today at the 8th International AIDS Society (IAS) Conference on HIV Pathogenesis, Treatment and Prevention in Vancouver, Canada. The new finding is from HPTN 068, the first individually randomized study of young women conditioned on school attendance with an HIV incidence endpoint. In the trial, young women and their parent/guardian were randomized to one of two study arms: 1) a monthly cash transfer of 300 rand ($30) per month conditional on 80 percent school attendance, or 2) a control arm that did not receive cash transfer. Provision of cash conditional on school attendance has been proposed as an intervention for young women at high risk of HIV infection based on studies showing that such transfers are an effective way to keep girls in school and studies showing that schooling reduces HIV risk. Cash transfers have also been hypothesized to reduce young women’s HIV risk by decreasing their dependence on older male partners and transactional sex.
“Cash transfers play a key role in social protection in many settings including South Africa, but in this study setting they were not protective for acquiring HIV,” said Audrey Pettifor, Ph.D., associate professor in the Department of Epidemiology at the University of North Carolina at Chapel Hill and HPTN 068 study protocol chair. “School attendance was very high for young women in both arms of the study and staying in school reduced the risk of HIV acquisition. Overall HIV risk was low in the study population, much lower than anticipated, which may have affected the findings from this trial.”
The study found that there was no difference in HIV acquisition between the young women who received the cash transfer and those that did not. There were 59 incident HIV infections in the intervention arm and 48 in the control arm (hazard ratio 1.17 (95% CI 0.80-1.71, p=0.43)). Overall HIV incidence was 1.8% during the study, lower than the study team expected. Surprisingly, school attendance was high during the study; 95% of girls in both arms attended school, and there was no difference in school attendance between study arms. In line with the original hypothesis of the trial, young women who stayed in school and attended school more of the time across both arms of the study had a two-thirds reduced risk of acquiring HIV.
A total of 2,533 young women were enrolled between March 2011 and December 2012. Two thousand four hundred forty eight (2,448) of the young women were HIV negative at enrollment. Participants enrolled in the study were aged 13-20 years, in high school, not married or pregnant, and resided in the Medical Research Council (MRC) / Wits University Agincourt Health and Socio-Demographic Surveillance System (AHDSS) study site. This region is a rural area of Mpumalanga Province in South Africa that is characterized by high HIV prevalence, poverty, and migration for work.
While the study did not find any difference in new HIV infections between the young women who received cash transfers and those who did not, the young women who received cash transfers reported significantly less risk behaviors. They reported having significantly fewer sex partners, less unprotected sex, and were less likely to experience intimate partner violence compared to the young women not receiving the cash. However, there were no significant differences between study arms in the number of young women reporting an older partner or engaging in transactional sex.
“Financial incentives offer enormous potential to influence health behaviors,” said Wafaa El-Sadr, MD, MPH, MPA, Professor of Epidemiology and Medicine at Columbia University Mailman School of Public Health and College of Physicians and Surgeons, director of ICAP and HPTN Principal Investigator. ”Findings from HPTN 068 are critical in informing the next generation of studies that aim to assess the role of financial incentives in prevention of HIV infection”
Young women in South Africa face an extremely high risk of HIV infection. More than 11 percent of young women ages 14 to 24 are living with HIV, compared to less than three percent of men in the same age group. The effect of cash transfers on HIV prevention for young women may depend on the local context. Cash transfers to keep girls in school may have a greater impact in settings where secondary school enrollment is low for young women. The effect of cash transfers to reduce HIV risk behavior through mechanisms other than school attendance will likely be dependent on factors driving HIV risk and how likely it is that those behaviors can be altered by cash, which will largely be dependent on the local context. Further analysis of the HPTN data is planned in order to help in understanding whether particular subgroups of young women may have benefited from the cash transfer and to identify factors that were protective for HIV acquisition, including school attendance, in this high prevalence area.
HPTN 068 was funded by the U.S. National Institutes of Health.
The HIV Prevention Trials Network (HPTN) is a worldwide collaborative clinical trials network that brings together investigators, ethicists, community and other partners to develop and test the safety and efficacy of interventions designed to prevent the acquisition and transmission of HIV. HPTN studies evaluate new HIV prevention interventions and strategies in populations and geographical regions that bear a disproportionate burden of infection. The HPTN research agenda is focused primarily on the use of integrated strategies: use of antiretroviral drugs (antiretroviral therapy and pre-exposure prophylaxis); interventions for substance abuse, particularly injection drug use; behavioral risk reduction interventions and structural interventions. The HPTN is committed to the highest ethical standards for its clinical trials and recognizes the importance of community engagement in all phases of the research process.