South Africa's Experience of the Closure of the Cellulose Sulphate Microbicide Trial

I n sub-Saharan Africa, almost 60% of HIV infections are among women [1], and the number of new HIV infections in women worldwide continues to escalate. The high incidence of HIV in many African countries provides the optimum environment for research on technologies that could prevent women from becoming infected, including microbicides. In this article, we discuss the recent highly publicised closure of a trial of cellulose sulphate (CS), which we conducted. We discuss the impact of the closure on the participants, the community at the trial site and the public at large, the public health sector, national regulatory bodies, the media, and on other ongoing microbicide trials. The local lessons that we learnt from the closure may provide guiding principles for researchers and advocates in the HIV prevention fi eld as a whole, who may face similar situations in the future. Vaginal microbicides are products which, when applied to the vagina, may prevent HIV transmission. Such a product would be particularly valuable for women who are unable to negotiate condom use with their partners, since its use would be initiated by the woman. The concept of a vaginal microbicide was tested several years ago using an over-the-counter spermicide, nonoxynol-9, a surfactant that acts by disrupting cell membranes. The trial, conducted in several African countries, showed an increase in risk of HIV among women who used the product more than three times a day [2]. The trial outcome was a huge setback for the microbicide fi eld. Nevertheless, almost a decade later, there are several products in large-scale clinical trials. These products were developed as a result of a better understanding of HIV-1 pathogenesis, including identifi cation of HIV target cells [3]. In 2006, there was another disappointment with the stoppage of two trials of C31G (known as SAVVY), an antimicrobial and spermicidal agent. The trials were stopped because the HIV incidence was lower than expected in the target population, and it was unlikely that the trials would be able to show effi cacy against HIV [4]. There were no safety concerns with the product. Of the current products in large-scale effectiveness trials, almost all belong to a class of compounds called fusion inhibitors. These act by preventing the virus from attaching to the target cells in the vagina. The current generation of products has poor specifi city to HIV. Two have contraceptive properties, three (BufferGel, Carraguard, and PRO 2000) …