Pre-Clinical Safety Evaluation of Antimicrobial Bioadhesive Vaginal Formulations

Background: The mucosal formulations are required to be evaluated for their safety and irritability. In present study the safety and irritability potential of antimicrobial acid buffering bioadhesive vaginal (ABBV) products having a pH of 4.4 were investigated. Methods: Four groups of female rats were administered 0.1ml sham negative control, ABBV gel, ABBV tablet and suspension of marketed formulation, for 14 consecutive days. Safety and irritability of ABBV products was assessed on the basis of daily observations (behavior, vaginal bleeding or discharge and pharmacotoxic signs), macroscopic mucosal surface (erythema, edema and discharge) and microscopic (inflammation, cell proliferation, edema and flattening of cells) observations. Results: In daily observations uneasiness was noticed for about 20 minutes for the first two days, in formulation treated groups. The reason for uneasiness may be the feeling of fullness of vaginal tube or first experience of grittiness or messiness of product. After the first two days there was no sign of uneasiness and animals behaved normally. There was no discharge, bleeding, erythema or edema. A mild parakeratosis was observed with Infa-V, ABBV tablet and gel treated groups. There was no sign of submucosal edema or inflammation in any group. Minimal irritation (score-1) was observed in formulation treated groups, while the irritability score of sham negative control was zero. Conclusion: ABBV formulations having pH 4.4 were found to be safe and non-irritating.