Definition

A virus-like particle (VLP) composed of the Qbeta bacteriophage capsid encapsulating the toll-like receptor 9 (TLR9) agonist G10, an unmethylated CpG-A oligodeoxynucleotide (ODN), with potential immunostimulating and antineoplastic activities. Upon administration of vidutolimod, the VLPs are specifically taken up by and release the oligonucleotide into antigen-presenting cells (APCs), including dendritic cells (DCs). In turn, the oligonucleotide binds to and activates intracellular TLR9. This stimulates immune signaling pathways, induces the innate immune system and may promote the immune system to attack tumor cells. VLPs stimulate the immune system. TLR9, a member of the TLR family, plays a key role in both pathogen recognition and the activation of innate immunity.