This is a randomized, double-blind, placebo-controlled Phase II study designed to determine if amoxicillin will eradicate vaginal colonization/infection with Gardnerella vaginalis (GV) when administered to women who are colonized/infected with GV but have no clinical evidence of Bacterial Vaginosis (BV). The study will be conducted at 2 clinics in the United States: University of Alabama at Birmingham and Wake Forest University Health Sciences. Entire study duration is approximately 10 months and subject participation duration is approximately 15 days. Approximately 245 healthy adult females, 18 to 45 years of age will be screened to enroll approximately 98 participants to achieve 82 evaluable participants at the test of cure (ToC) visit. Participants will be enrolled and randomized to one of two groups, either amoxicillin (2 x 250 mg capsules by mouth twice daily for 7 days) or placebo. Women who are enrolled will be asked to return for one further visit, Visit 2 (Day 15 - 21), where a ToC will be completed. For those not enrolled, participation will end at their post screening follow up phone call. Women will be asked to use condoms during their participation. The primary objective is to determine if treatment with amoxicillin eradicates GV in women who are colonized/infected with GV but have no clinical evidence of BV.