Tagraxofusp (Elzonris)

Mechanism of action

From the NCI Drug Dictionary: A recombinant protein consisting of human interleukin 3 (IL3) fused to the first 388 amino acids of diphtheria toxin [DT(388)] (DT388IL3) with potential antineoplastic activity. Upon intravenous administration, the IL3 moiety of the tagraxofusp-erzs binds to IL3 receptors on cells expressing the receptor. Subsequently, the DT(388) toxin moiety, which contains both translocation and catalytic domains, is transported across the cell membrane via endocytosis. Within the cytosol, the catalytic domain of the toxin both catalyzes the ADP-ribosylation of, and inactivates, translation elongation factor 2 (EF-2), which results in the inhibition of translation during protein synthesis.

Diseases for which it is established

• Blastic plasmacytoid dendritic cell neoplasm

History of changes in FDA indication

• 2018-12-21: Initial approval for blastic plasmacytoid dendritic cell neoplasm (BPDCN) in adults and in pediatric patients 2 years and older. (Based on STML-401-0114)

History of changes in EMA indication

• 2021-01-07: Initial authorization as Elzonris

Also known as

• Code name: SL-401
• Generic name: tagraxofusp-erzs
• Brand name: Elzonris