Ad-e23(scFv)-PE40

Ad-e23(scFv)-PE40 is a recombinant gene therapy agent consisting of an **adenoviral vector** (Ad) encoding a fusion immunotoxin that targets **c-erb-B2 (Her-2/neu)**, a protein commonly overexpressed in pancreatic and other cancers[3]. The construct contains a **single-chain variable fragment (scFv)** derived from an anti-c-erb-B2 antibody (e23), fused to **PE40**, a truncated, catalytically active fragment of Pseudomonas exotoxin A[3]. The adenovirus acts as a delivery vehicle to introduce the gene for the immunotoxin directly into target cancer cells, which subsequently express the cytotoxic agent, selectively killing c-erb-B2–positive tumor cells. Preclinical studies in mice demonstrated significant inhibition of pancreatic tumor growth when Ad-e23(scFv)-PE40 was administered, especially in combination with a replication-competent adenovirus and low-dose etoposide, with no overt systemic toxicity observed[3][1].