Cellulose sulfate

Cellulose sulfate was a candidate microbicide that had been stopped for regulatory approval to be used therapeutically in the prevention of the spread of sexually transmitted diseases.

On February 1 2007, the International AIDS Society announced that two phase III trials of cellulose sulfate had been stopped because preliminary results suggested a potential increased risk of HIV in women who used the compound.

At present, there is no explanation as to why cellulose sulfate was associated with a higher risk of HIV infection than placebo.

Although the halting of the two trials was a disappointing setback for microbicide research, the investigators received praise for acting quickly as soon as an adverse effect had become apparent.

According to a review of microbicide drug candidates by the World Health Organization on March 16 2007 a large number of compounds - more than 60 at the start of 2007 - are in the development pipeline. And at the beginning of that year, five phase III trials testing different formulations were under way.

As for these remaining late-stage microbicide trials, if they prove successful, first-generation products could be available by 2009. If they fail, second-generation products could become available by 2012.

ee also

*Carrageenan