Design and evaluation of mucoadhesive capsule formulations of live biotherapeutic product for vaginal delivery of lactobacillus SPP

Abstract

Live biotherapeutic products (LBPs) represent a promising therapeutic platform for women's health, primarily by addressing vaginal and reproductive conditions through microbiome modulation. This study explores the design and evaluation of mucoadhesive capsule formulations for targeted, continuous delivery of Lactobacillus spp., directly into the vaginal cavity. By leveraging the anatomical and physiological features of the vagina, together with an understanding of the mucoadhesive and drug-release properties of several polymers, the research aims to optimise localised drug delivery of a living bacterial strain. Various capsule shells, polymers and polymer combinations were assessed for physico-chemical and biorelevant properties, as well as bacterial viability. Pullulan capsules demonstrated superior mucoadhesive properties, and the formulation combining Carbomer and PEO emerged as optimal, offering sustained adhesion and viable bacterial delivery in simulated vaginal conditions. These findings underscore the potential of mucoadhesive LBPs in enhancing vaginal health through targeted, prolonged and biocompatible delivery systems.