VSV-CD40L

**VSV-CD40L** is a genetically engineered, replication-competent oncolytic virotherapy based on vesicular stomatitis virus (VSV) modified to express the immune-stimulatory molecule CD40 ligand (CD40L). The primary mechanism is to combine the oncolytic properties of VSV, which preferentially replicates in and lyses tumor cells (especially those with defective type I interferon responses), with the enhanced immune activation capabilities of CD40L, a potent T cell co-stimulatory molecule that acts via CD40 on antigen-presenting cells to augment anti-tumor immune responses. In preclinical models, VSV-CD40L has been studied primarily for cancer immunotherapy, notably in melanoma. However, its efficacy is comparable to unmodified VSV in some models, possibly due to the already strong immunogenicity of VSV masking any additive effect of CD40L.