MEDIA CENTER
Microbicides News

NEW YORK, NY (25 July 2007) — Earlier this year CONRAD and Family Health International (FHI) halted their Phase 3 clinical trials of cellulose sulfate, a candidate microbicide. Microbicides are products being developed to reduce the transmission of HIV—and possibly other sexually transmitted infections—when used during intercourse.

A preliminary review of the data by an independent monitoring group had indicated that use of cellulose sulfate was associated with an increased risk of HIV infection, leading CONRAD and FHI to stop the trial immediately. On 25 July, additional analysis of cellulose sulfate, a cotton-based contraceptive microbicide candidate, was presented at the International AIDS Society meeting.

This analysis confirmed that cellulose sulfate is not an effective method of preventing HIV transmission and may increase a woman’s susceptibility to HIV infection. Cellulose sulfate was one of four first-generation microbicide candidates in trials to determine their effectiveness in preventing the transmission of HIV and other sexually transmitted infections.

The Population Council has been working for nearly two decades to develop safe and effective vaginal microbicides. The Council's first-generation candidate microbicide, Carraguard®, is a noncontraceptive product made from carrageenan, which is derived from seaweed. Carrageenan has been used for many years as a thickener in baby foods, skin lotions, and toothpaste.

Data collection for a large-scale Phase 3 efficacy trial of Carraguard involving over 6,000 women in South Africa was completed on 31 March 2007 with results expected at the end of 2007. An external, independent monitoring group reviewed the trial data at three interim points during the trial and judged that there was no increased risk of HIV infection among Carraguard users or any other significant safety risks to trial participants, so the trial continued to its scheduled completion. Carraguard had been found to be safe and acceptable for vaginal use in earlier studies with more than 600 women and men in Australia, Chile, the Dominican Republic, Finland, South Africa, Thailand, and the United States.

Population Council research has demonstrated that Carraguard prevents HIV transmission in the laboratory. Only a clinical trial can reliably predict the efficacy and long-term safety of any microbicide in humans.

For more information:

• CONRAD  (offsite link)
• Family Health International (offsite link)

---

See Also

• Population Council Microbicides Program

---