Preclinical Evaluation of Tolerability of a Selective, Bacteriostatic, Locally Active Vaginal Formulation

BACKGROUND: Polybactum (Effik International, Brussels, Belgium) is a vaginal mucoadhesive product (medical device) designed to form a film that acts as a mechanical barrier with the aim of inhibiting colonization by specific pathogens. It contains polycarbophil, a bioadhesive agent, and lauryl glucoside (LG), a nonionic surfactant that reinforces the barrier effect through its tensioactive properties. OBJECTIVE: To assess the local safety profile, tolerability, and efficacy of Polybactum formulations. METHODS: The following studies were performed on 3 Polybactum formulations: 2 ovules (Type 1: LG 0.04% and Type 2: LG 0.1%) and 1 gel formulation. Bacteriologic tests assessing the effects on normal vaginal flora and pathogens; in vitro and in vivo tests designed to assess cytotoxicity, as well as irritant and sensitizing potentials; biocompatibility, barrier, residence time, and absorption tests using reconstituted human vaginal epithelium were performed. RESULTS: Polybactum is a selective bacteriostatic agent that is active against Streptococcus agalactiae and Gardnerella vaginalis while sparing normal vaginal flora; that is, Lactobacillus spp. It had no cytotoxic, irritant, and sensitizing effects nor did it impair barrier and fence functions of the vaginal epithelium. The Type 1 ovule showed film-forming properties in vitro. Finally, LG absorption through reconstituted human vaginal epithelium was negligible, ruling out the risk for possible systemic toxicity. CONCLUSIONS: This favorable preclinical profile is encouraging and supports clinical studies on Polybactum Type 1 ovules for the prevention and management of recurring bacterial vaginosis.