Combined Retinoic Acid,Arsenic Trioxide and Chemotherapy for Newly-diagnosed Acute Promyelocytic Leukemia: Chinese National Multi-center Randomized Study

The study is carried out based on Sanz risk stratification of newly-diagnosed APL patients into low-, intermediate- and high-risk groups, and all of them will receive ATRA and ATO as induction therapy (ATRA 25 mg/m2 per day orally + ATO 0.16mg/kg intravenously daily). Anthracycline is added to both high-risk groups or intermediate-risk group with hyperleukocytosis developed during induction therapy but not in low-risk groups.

After achieving CR, patients enter into consolidation therapy. Low-risk patients receive either 2 courses of ATRA plus ATO (Experimental group) or 2 courses of ATRA plus anthracycline chemotherapy (Control group). Intermediate-risk patients receive either 3 courses of ATRA plus ATO (Experimental group) or 2 courses of ATRA plus anthracycline chemotherapy (Control group). Patients of high-risk disease receive 2 courses of ATRA plus ATO and anthracycline and 1 course of ATRA plus ATO treatment (Experimental group) or 2 courses of ATRA plus anthracycline and cytarabine and 1 course of ATRA plus mid-dose cytarabine (Control group).

After consolidation therapy, patients with molecular complete remission (mCR) enter into maintenance therapy. Low- and intermediate-risk patients receive 3 cycles of ATRA and ATO sequential treatment, while those of high-risk receive 5 cycles of ATRA, ATO and methotrexate (MTX) treatment.

For low- and intermediate-risk patients who fail to achieve mCR after consolidation therapy, 3 courses of consolidation therapy of high-risk group will be given with cross-over (i.e. patients in Experimental group received the therapy of Control group, and patients in Control group received the therapy of Experimental group). If patients still fail to achieve mCR, together with high-risk group who fail to achieve mCR after consolidation therapy will be withdrawn from the study and proceed to salvage treatment.