PZ671 is a potent PROTAC degrader targeting Bcl-xL, exhibiting an IC50 of 1.3 nM in MOLT-4 cells and a DC50 of 0.9 nM for Bcl-xL. It induces apoptosis in MOLT-4 cells and effectively inhibits tumor growth in MOLT-4 xenograft mice, while quickly restoring transiently reduced platelet counts. PZ671 is applicable in cancer research, including studies on small cell lung cancer.

PZ671 (Compound 5b) at concentrations of 0.4-100 nM over 1-16 hours can induce the degradation of Bcl-xL in MOLT-4 cells. Using PZ671 at 10 and 100 nM results in proteasome-dependent Bcl-xL degradation within these cells. Additionally, PZ671 ranging from 0.4-100 nM over 48 hours can trigger apoptosis in MOLT-4 cells. Moreover, concentrations between 30-1000 nM for 48 hours, exceeding 1 μM, lead to Bcl-xL degradation in human platelets.

PZ671 (1.5 mg/kg; intraperitoneal injection; every 4 days for 22 days) significantly inhibits tumor growth in MOLT-4 xenograft mice; however, it causes a transient drop in platelet count that rapidly recovers starting the day after administration.