Cellulose sulfate ruled out as a microbicide candidate
Final results are available from a randomized controlled trial testing the effectiveness of cellulose sulfate as a vaginal microbicide. Reported in The New England Journal of Medicine, they confirm that cellulose sulfate is unlikely to prevent the transmission of HIV and might even increase a woman's risk of HIV infection.
The Cellulose Sulfate Study Group, composed of a wide range of international partners including CONRAD and Family Health International, conducted the trial with partial support from USAID. The trial involved three sites in Africa and two sites in India. Nearly 1,400 women at high risk of HIV infection participated.
The trial randomly assigned these women to use either a 6 percent cellulose sulfate gel or a placebo gel during each act of sexual intercourse over a one-year period. However, the trial halted early (on the recommendation of an independent data monitoring committee) because of a potential increased risk of HIV transmission in women using the cellulose sulfate gel.
The final data show 41 HIV infections — 25 in the cellulose sulfate group and 16 in the placebo group. Although more women in the cellulose sulfate group were infected with HIV during the study, the difference between the two groups is not statistically significant. Nevertheless, these data are sufficient to rule out cellulose sulfate as a candidate microbicide.
Van Damme L, Govinden R, Mirememba FM, Guédou F, Solomon S, Becker ML, Pradeep BS, Krishnan AK, Alary M, Pande B, Ramjee G, Deese J, Crucitti T, Taylor D, CS Study Group. Lack of effectiveness of cellulose sulfate gel for the prevention of vaginal HIV transmission. N Engl J Med 2008;359(5):463-472.