Fused Deposition Modeling-Based 3D Printing as a Versatile Technology to Manufacture Vaginal Films Incorporating Metronidazole

Bacterial Vaginosis (BV), characterized by the overgrowth of pathogenic bacterial species in the female genital tract, is a prevalent vaginal condition among women aged 15–44 years. Metronidazole (MTZ), a nitroimidazole antibiotic, is commonly used to treat BV. However, existing MTZ dosage forms such as gels and suppositories can cause leakage, messiness, potential drug loss, and reduce patient adherence. This study demonstrates the feasibility of 3D printing method for manufacturing MTZ-loaded vaginal films at clinically relevant dose and with varied mucoadhesion.

Fused deposition modeling (FDM)-based 3D printing was utilized for printing vaginal films from hot-melt extruded MTZ filaments. Two different formulation compositions of MTZ films were investigated to demonstrate the method’s versatility and to produce films with varying performance attributes. Films were characterized for drug content, mechanical and thermal properties, in vitro drug release, mucoadhesion, and cytotoxicity.

Soft and flexible vaginal films loaded with 37.5 mg MTZ were successfully manufactured using 3D printing. The two formulations investigated showed differences in drug release and mucoadhesion. Films were compatible with commensal vaginal Lactobacilli and showed no negative impact on the viability of vaginal epithelial cells.

The study demonstrates the feasibility of utilizing 3D printing as an effective, robust, and viable manufacturing method for producing MTZ vaginal films for BV treatment. These films can offer precise dosing, improved bioretention, and enhanced patient adherence without leakage, positioning them as a promising alternative to existing MTZ dosage forms.