Cellulose Sulfate Microbicide Trial Stopped
A Phase III study of the candidate microbicide cellulose sulfate to prevent HIV transmission in women has been stopped prematurely because of a higher number of HIV infections in the active compared with the placebo group. The study was sponsored by CONRAD and conducted in Benin, India, South Africa and Uganda. A second study on the same product sponsored by Family Health International conducted in Nigeria has also been stopped because of the safety concerns in the first trial. This is a disappointing and unexpected setback in the search for a safe and effective microbicide that can be used by women to protect themselves against HIV infection. Cellulose sulfate was one of four compounds being evaluated in large-scale studies of effectiveness among women at high risk of HIV infection.
Currently there are three other Phase III microbicide studies under way. The Carraguard study (sponsored by the Population Council and conducted in three sites in South Africa) is nearing completion and results are expected by the end of 2007. Another product, PRO 2000, is being tested in one study in five sites in South Africa, Tanzania and Uganda (results expected in 2009) as well as in a second study in seven sites in Malawi, South Africa, Zambia and Zimbabwe (results expected in 2008). In this second study a further compound, BufferGel, (a vaginal defence enhancer) is being tested. All the other compounds mentioned are products that block HIV infection