Fourteen-day safety and acceptability study of 6% cellulose sulfate gel: a randomized double-blind Phase I safety study.

Background: Topical microbicides against the human immunodeficiency virus (HIV) 1 that are nonirritating to the female genital epithelium are urgently needed to slow the heterosexual spread of HIV infection. Products that are also effective contraceptives provide additional benefits. Cellulose sulfate (CS) is a noncytotoxic antifertility agent that exhibits in vitro antimicrobial activity against sexually transmitted pathogens, including HIV.

Methods: We performed a multicenter, Phase I, placebo-controlled, randomized study to evaluate the genital toxicity of CS. Two cohorts of healthy women used 3.5 ml of 6% CS gel or 3.5 ml of K-Y Jelly, vaginally, bid, for 14 days. The first cohort was sexually abstinent, and the second cohort was sexually active.

Results: CS was associated with only a slightly higher odds ratio (OR) of symptoms of minor urogenital irritation compared to the inactive lubricant K-Y Jelly (OR=2.02, 95% confidence interval=0.90-4.53). In addition, there were minor shifts in some genital flora, but there was no evidence of greater inflammation as evidenced by few colposcopic findings, decreased influx of polymorphonuclear cells and minimal changes in proinflammatory cytokines. Moreover, both products appeared acceptable to most women. Product leakage was identified as more of a problem in sexually abstinent women, but less so in women using the product for sexual intercourse, as would be the case in actual practice.

Conclusion: CS was safe for twice-daily use for 14 days. CS is appropriate for future studies in effectiveness trials.