Prolonged, transplant-free remission with tagraxofusp in combination with venetoclax for transplant-ineligible blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare, aggressive hematologic malignancy predominantly affecting older adults. While the CD123-directed agent tagraxofusp has improved outcomes, durable long-term survival is typically limited to patients eligible for transplant, leaving effective transplant-free treatment strategies as an urgent unmet need. Here, we report the case of an 84-year-old woman with concurrent Rai stage 0 chronic lymphocytic leukemia (CLL) who presented with skin-limited BPDCN and was treated with tagraxofusp and venetoclax combination therapy. The patient achieved a clinical complete remission exceeding four years, with only mild capillary leak syndrome during cycle one of tagraxofusp as well as intermittent grade 1 neutropenia as toxicities. To our knowledge, this represents the longest reported duration of tagraxofusp-based therapy in BPDCN. This outcome aligns with emerging evidence supporting synergy between CD123-targeted therapies and BCL2 inhibition, including recent data from a tagraxofusp-azacitidine-venetoclax triplet regimen demonstrating improved outcomes compared to tagraxofusp monotherapy. This case suggests that combination therapy strategies may enable prolonged, transplant-free remission in BPDCN, a finding of particular significance given the older, often transplant-ineligible population disproportionately affected by this disease.