Microsoft word - summary of mitu research programme final.doc

Mwanza Intervention Trials
SUMMARY OF RESEARCH STUDIES CARRIED OUT BY THE MWANZA
INTERVENTION TRIALS UNIT
The Mwanza Intervention Trials Unit (MITU) builds on a long history of collaborative research on HIV and related infections in Mwanza and other neighbouring regions in North-western Tanzania. This collaboration involves the Tanzania National Institute for Medical Research (NIMR), and the London School of Hygiene and Tropical Medicine (LSHTM). The Unit is located in a new building on the NIMR campus in Mwanza City. Since its inception in the late 80’s, the research collaboration has focused mainly on the development and evaluation of interventions against HIV and other sexual health problems, generally through the conduct of randomised controlled trials. A series of groundbreaking studies have been carried out on HIV prevention and related topics, that are widely known by the international scientific community. The first major HIV prevention trial, often known as “the Mwanza trial”, was conducted between 1990 and 1995. This study showed that improved treatment services for sexually transmitted infections (STIs) reduced HIV incidence in the general adult population by 40%. This was the first randomised trial anywhere in the world to demonstrate the impact of an intervention programme on HIV incidence in the general adult population. The findings of this trial have had a substantial influence on AIDS control policies in many parts of the world. This was followed by a further community-randomised trial (MEMA kwa Vijana), to measure the impact of adolescent sexual and reproductive health interventions. The interventions comprised of school-based sexual health education delivered through teacher-led, peer-assisted classroom sessions, combined with the provision of youth-friendly reproductive health services at local government clinics, youth condom promotion and distribution, and supportive community-wide activities. The trial was conducted in 20 rural communities, and the impact of the intervention was assessed in a cohort of over 9,000 adolescents aged 14 years and over at recruitment. The first phase of the trial commenced in 1998 and was completed in 2002. Results of the impact evaluation in 2001-2 (three years after the start of the intervention) showed that the intervention had led to significant improvements in knowledge, reported attitudes and some reported sexual behaviours, but did not lead to a significant reduction in the rates of HIV infection and prevalence of HSV-2 and other STIs. A further survey to evaluate the long-term impact of the intervention was completed in 2008 (eight years after the start of the intervention). This survey showed that the correct knowledge and desirable reported attitudes related to sexual risk were higher in intervention communities than in comparison communities. However, there was no evidence that the intervention led to a reduction or increase in the prevalence of HIV infection, HSV-2 and other primary biological outcomes. Recently, we completed another trial designed to assess the impact of long-term suppression of Herpes simplex virus type 2 (HSV-2) infection, using a standard regimen of acyclovir, on HIV-1 acquisition. This trial was also designed to examine the long-term effect of HSV-2 suppressive therapy on detection and quantity of HIV-1 RNA in the genital secretions. There is evidence that the sexual transmission of HIV is enhanced in the presence of HSV-2, the main causative agent for genital herpes. In this trial, females aged 16 to 35 years (N=821) in 19 communities in northwest Tanzania who worked in bars, guesthouses, and other food and recreational facilities were enrolled between January 2004 and May 2006. Results from this trial showed that there was no significant effect of twice-daily treatment with acyclovir on the incidence of HIV infection among the participants in this study. There was also little evidence of an effect of acyclovir on either detection or quantity of cervicovaginal HIV-1 RNA, indicating that this was not a viable public health intervention for prevention of HIV infection. Following on from this research, two large randomised controlled trials are now in progress. Microbicides have the potential to put the power of protection from HIV infection into the hands of women and minimise the impact of the epidemic among women. MITU is conducting a phase III randomised, double-blind, placebo-controlled trial to evaluate the safety and efficacy of a candidate vaginal microbicide known as PRO 2000/5 in prevention of HIV among high-risk women. This study is conducted at six sites in sub-Saharan Africa, including the Mwanza site, as part of a DFID supported consortium of UK and African institutions for a Microbicides Development programme (MDP). Between 2006 and 2008, 9,392 women were enrolled across the six sites and follow-up was completed in July 2009. The second trial is being carried out in Mwanza to evaluate the immunogenicity and safety of a vaccine against human papillomavirus (HPV) types 16 and 18. Up to 70% of cervical cancer cases are caused by HPV types 16 and 18. Therefore the development of vaccines to prevent infections with those types of virus would be of great value. The trial has enrolled over 300 women, 10 to 25 years of age, are randomised into two groups; one group will receive 3 doses of vaccine against HPV-16 and HPV-18 and one group will receive a placebo. The response and safety of the vaccine at different points in time over a year and for various age groups will be evaluated, and information about risk factors for occurrence of HPV and other STIs will be collected. In addition to the above clinical trials, a number of observational studies are ongoing in Mwanza. This includes a prospective cohort study of women at increased risk of HIV (Women’s Health Project) at two major mining sites and one site along a major highway in Mwanza and Shinyanga regions. This study aims to estimate HIV incidence and assess feasibility of conducting future trials of HIV interventions in this population, including trials of candidate microbicide products. Within this cohort, we are conducting a sub-study to describe and quantify the types of intravaginal practices (IVP) among women in the study, and investigate the relationships between IVP and other STIs, including HIV infection. We are also strengthening local research capacity and conducting observational studies in preparation for clinical trials of candidate HIV vaccines. The studies aim to characterise high-risk populations in Mwanza and Moshi; and to determine the distribution of HIV-1 genotypes and the immunological and genetic factors that could confer resistance to HIV or slow down the progression of HIV disease.

Source: http://lists.cidglobal.net/pipermail/allcids-cidglobal.net/attachments/20090821/04c9ca71/attachment-0003.pdf