Intravenous Busulfan (iv-Bu) is commonly used as part of preparation regimen for allogeneic hematopoietic stem cell transplantation for patients with acute leukemia. Though the pharmacokinetics data are available for population from America, Europe and Japan or Korea in Asia, there are no data in Chinese population. It is shown that high Bu concentration are associated with the toxicity such as veno-occlusion disease and lower concentration is correlated with reduced anti-leukemia effect, thus the monitoring of Bu and/or the strategy to achieve an optimal target Bu concentration are accepted to avoid toxicity while maintain the anti-leukemia effect which may overall improve the outcome of allo-SCT. Thus we conduct the pharmacokinetic study in Chinese population.

All patients received intravenous Busulfan based conditioning regimen for allogeneic stem cell transplantation.

Intravenous Busulfan (iv-Bu) was given 1.6mg/kg twice daily for 4 days as in the conditioning regimen.

Blood samples were obtained after first and 7th dose of iv Bulsulfan.

Inclusion Criteria:

• patient with acute myeloid or lymphoblastic leukemia in 1st or second remission
• age 18-55 years
• with inform consent
• no contraindication for allogeneic transplantation: active infection, allergy to FLu/Bu/CTX, liver and renal function damage
• HLA matched related (6/6) or unrelated donors (at least 8/10)

Exclusion Criteria:

• age less than 18 years or over 56 years
• HLA mismatched related donor
• liver function/renal function damage (over 2 X upper normal range)
• with mental disease