In this first-in-human volunteer phase I clinical trial, a vaginal ring that slowly releases lactic acid (racemic mixture) into the vaginal environment, will be inserted in healthy volunteering women and left in place for 7 days. The primary objective of this phase I study is to assess the safety and the tolerability of this new intravaginal delivery system.

The eventual goal of this and related studies is to develop a vaginal ring that reduces recurrences in women suffering from bacterial vaginosis, which is the commonest form of vaginal infection.

Inclusion Criteria:

• Good general physical and mental health
• Presence of normal (lactobacilli-dominated) vaginal microbiota
• Prepared to take oral contraception during the study

Exclusion Criteria:

• Pregnancy
• Lactation
• Systemic disease
• Menopause
• Recent use of antibiotics (<1 week before entering the study)
• Recent use of intravaginal products or devices (<1 week before enrolment)
• Presence of vaginal infection