Flaviviruses, including dengue virus (DENV) and Zika virus (ZIKV), continue to represent a serious global health challenge, with their spread into new regions highlighting the urgent need for novel antiviral strategies. Current therapeutic options are limited, and available vaccines face constraints in efficacy and safety, emphasizing the importance of alternative approaches capable of effectively counteracting infections caused by these viruses.

In this study, we investigated two antiviral molecules developed in our laboratory. Compound pep14-23 was previously shown to have antiviral activity against ZIKV and is now being evaluated for its effects on other flaviviruses. In parallel, we are assessing a newly developed molecule designed based on a different strategy.

Vero 81 cells were infected with ZIKV or DENV and treated with each molecule. Viral replication was monitored using plaque assays for ZIKV and indirect immunofluorescence for DENV. In ZIKV-infected cells, pep14-23 caused only a modest decrease in viral replication, whereas the new molecule exhibited strong inhibition at both 12 and 24 hours post-treatment. In DENV-infected cells, pep14-23 showed no significant effect, while the new molecule achieved near-complete suppression of viral replication, with no detectable DENV from 3 to 24 hours.

Overall, these studies provide important insights into the translational potential of these molecules, opening new avenues for their development as innovative tools for antiviral intervention and integrated vector control strategies.