Ozonated water hydrogel: a promising therapeutic agent for targeting high-risk HPV infections

Cervical cancer, primarily caused by high-risk human papillomavirus (HPV) subtypes 16 and 18, remains a global health challenge, particularly in resource-limited regions where HPV vaccine accessibility is constrained by cost and logistical barriers. This study investigates ozonated water (OW) and its hydrogel formulation (H-OW2) as novel antiviral agents against HPV. OW exhibited dose-dependent inactivation of HPV16/18 pseudoviruses, achieving >98% inhibition at 1 mg/l (OW3). However, unformulated OW demonstrated significant cytotoxicity at higher concentrations (49.24% cell viability for OW3) and rapid ozone decay (80% loss within 6 h). To address these limitations, H-OW2 was developed using a chitosan-calcium chloride hydrogel matrix. Remarkably, H-OW2 maintained >97% antiviral efficacy against both HPV subtypes for 14 days at room temperature, with negligible ozone degradation. The hydrogel formulation of OW also reduced oxidative stress in human cells, lowering reactive oxygen species levels to 4.046% and preserving mitochondrial membrane potential (92.05% of control). Critically, H-OW2 production costs are substantially lower than HPV vaccine, and its stability eliminates cold-chain requirements. These findings position H-OW2 as a cost-effective, stable, and safe topical prophylactic, offering a practical alternative or adjunct to vaccines in underserved populations. Further studies should validate its efficacy in vivo and optimize dosing regimens for clinical translation.