Real-world study of tagraxofusp monotherapy in relapsed or refractory blastic plasmacytoid dendritic cell neoplasm.

Patients with relapsed/refractory blastic plasmacytoid dendritic cell neoplasm (BPDCN) have limited treatment options. Tagraxofusp is the only drug approved for BPDCN. To provide real-world data on tagraxofusp in clinical practice, we report an analysis of safety and efficacy in adults who obtained tagraxofusp via a European named-patient program. Twenty-four patients (median age 68 years) with relapsed/refractory BPDCN received tagraxofusp 12 μg/kg intravenously days 1-5 of a 21-day cycle. Twenty patients (efficacy-evaluable) had a 65% overall response rate (ORR), 9.5-month median duration of response, 3.6-month median progression-free survival, and 8.4-month median overall survival (OS). Ten patients bridged to HSCT with a median OS not reached. There were no new safety signals. Capillary leak syndrome was manageable, mostly occurring during cycle one. These results support tagraxofusp for relapsed/refractory BPDCN after prior chemotherapy. Furthermore, the high transplant rate suggests tagraxofusp offers an opportunity for bridge to transplant in this difficult-to-treat population.