Hot‐Melt Extrusion: Manufacturing of Ethylene‐Vinyl Acetate Implants With Antiviral Controlled Release.

Herpes simplex virus types 1 and 2 (HSV‐1 and HSV‐2) are notable for their prevalence among the human population, being transmitted through direct contact or sexually, often in the absence of symptoms. HSV infections are chronic, characterized by a latent phase marked by episodic reactivations. Current treatments primarily rely on oral antiviral medications, particularly acyclovir (ACV), which, despite its effectiveness in inhibiting viral DNA replication, suffers from low bioavailability and requires high dosing, limiting patient adherence. Ethylene‐vinyl acetate (EVA) is widely used as a non‐degradable polymer in drug delivery systems. In this work, some EVA implantable rods with different ACV loads (0, 10, and 20 wt.%) were manufactured by hot‐melt extrusion. DSC analysis was useful to verify that the drug was successfully incorporated into the EVA matrix, which was also confirmed by SEM and FTIR. Mechanical tests were carried out on DMA and showed that the flexural modulus increased slightly with drug content, whereas the fatigue behavior was not significantly affected. Furthermore, the in vitro tests suggested a burst release on the first day followed by a lower release rate sustained up to 45 days. Therefore, these rods presented promising results and can be useful for the long‐term treatment of Herpes. [ABSTRACT FROM AUTHOR]