Expanded Phase I safety and acceptability study of 6% cellulose sulfate vaginal gel
ABSTRACT An expanded Phase I trial was performed to assess the safety and acceptability of 6% cellulose sulfate gel (CS) in comparison with K-Y Jelly.
Sexually abstinent (cohort I) and sexually active (cohort II) women in India, Nigeria and Uganda applied 3.5 ml of either 6% CS gel or K-Y Jelly for seven consecutive days. Safety was assessed by symptoms and signs (including colposcopy) of genital irritation, review of adverse events, and by changes in vaginal health as assessed by microscopy.
One hundred and eighty women (90 on CS and 90 on K-Y Jelly) were enrolled. Baseline characteristics of women in both gel groups were similar. In cohort I, six (14%) women on CS and 12 (27%) on K-Y Jelly reported genital symptoms, two (in K-Y Jelly group) of whom withdrew from the study. New colposcopy findings or findings showing deterioration were detected in four (9%) women on CS and nine (21%) women on K-Y Jelly in cohort I. Two women on CS and three on K-Y Jelly in cohort II reported genital symptoms. Five women (11%) in each gel group in cohort II had new colposcopy findings or findings showing deterioration. The differences between the gel groups were not statistically significant. The majority of women had no problem with their assigned product.
A vaginal application of 6% cellulose sulfate twice daily for seven consecutive days is as safe and well tolerated as a similar regimen of K-Y Jelly. Further development of 6% CS for prevention of HIV and pregnancy is recommended.
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ABSTRACT: Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections (STIs) including HIV-1. Despite more than two decades of HIV-1 vaccine research, there is still no efficacious HIV-1 vaccine, and the scientific community appears skeptical about the short or long-term feasibility of developing a vaccine that has the ability to induce sterilizing immunity against HIV-1. In this setting, microbicide research has gathered momentum. Currently, 16 candidate microbicides are in clinical development and five products are being evaluated in large-scale Phase 2B/3 effectiveness studies. Initial data from these trials will be available within the next 2-3 years, and it is feasible that there could be one or more licensed microbicides by the end of the decade. The first generation of surfactant microbicides had a non-specific mechanism of action. However, subsequent candidate microbicides have been developed to target specific steps in the process of viral transmission. The purpose of this article is to provide an overview of microbicide development and an update on the candidate pipeline.Biologicals 01/2007; 34(4):241-55. DOI:10.1016/j.biologicals.2006.08.002 · 1.41 Impact Factor