Safety, Acceptability and Preliminary Effectiveness of PC-515 for Vaginal Use as a Possible Microbicide

Inclusion Criteria: * In good health as determined by medical history, physical examination and results of laboratory screening tests * Aged 18 years or older * Resident in the area for at least one year and planning to stay for at least 12 months * HIV-seronegative at baseline * Willing and able to comply with the study protocol (including being tested for HIV, learning the results, and undergoing clinical evaluations) * Able to achieve a score of 80% or better on true-false test of key study concepts * Able to give informed consent Exclusion Criteria: * Pregnant or desire to become pregnant at time of study participation * Delivered or aborted a pregnancy within the six weeks prior to screening * Male sex partner known at enrollment to be HIV positive * History of surgery on external genitalia, vagina or cervix in the six weeks prior to screening * Recent history of non-menstrual vaginal bleeding with intercourse * Clinically detectable genital abnormality (including presence of warts, or a structural or congenital abnormality) * Clinical suspicion of a reproductive tract infection (RTI), defined as the presence of a genital ulcer visible to the naked eye, an abnormal vaginal discharge or purulent cervicitis, or untreated positive STD result (Women could be enrolled after treatment of identified RTI. Women with persistent genital epithelial disruption, i.e., ulcer, abrasion or fissure, were not eligible. * Women with other persistent abnormal signs, such as vaginal or cervical discharge, despite treatment of identified RTI, were eligible) * Abnormal Pap smear (Class II or above) * History of sensitivity/allergy to latex * Concurrent participation in another trial of a vaginal product * Injection of recreational drugs