VCN‐01 is an engineered OAd derived from ICOVIR‐5 to replicate in cancer cells with defective RB pathway and to express PH20 hyaluronidase enzyme, which helps degrade the extracellular matrix, particularly the hyaluronic acid‐rich tumor stroma, facilitating better viral spread and enhancing the delivery of chemotherapy [100]. The gene discussed is RB1; the disease is cancer.