Optimizing capillary leak syndrome prevention and management in patients receiving tagraxofusp for blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is an aggressive, orphan hematologic malignancy characterized by cells expressing CD123 and other markers. The only drug approved for BPDCN is tagraxofusp, a first-in-class CD123-targeted therapy. Tagraxofusp has a boxed warning for capillary leak syndrome (CLS) in the US prescribing information. CLS symptoms include hypoalbuminemia, weight gain, edema, and in severe cases, hypotension and hemodynamic instability. In the tagraxofusp registrational trial, 21% of patients receiving 12 µg/kg/day developed CLS. Most events were grade 2; higher grade CLS events including 2% grade 3, 2% grade 4, and two deaths occurred. During tagraxofusp treatment, strict monitoring for early recognition of CLS symptoms and directed intervention is essential for managing CLS; with this approach CLS is typically mild and occurs mostly in cycle 1, without recurrence. We discuss patient selection and optimization, monitoring, and early intervention for successful identification and optimized management of CLS in real-world practice.