CAV Regimen Bridging to HSCT for R/R AL

The enrolled patients will be firstly given CAV bridging regimen (cladribine 5mg/m2/ day for 5 days, cytarabine 20mg q12h for 10 days, and began at 100 mg on day 1 and increased stepwise over 3 days to reach the target dose of 400 mg (100 mg, 200 mg, and 400 mg) on days 1-21. Conditioning regimen for allo-HSCT may be administrated after completion of the CAV regimen, with or without consolidation therapy.