Ruxolitinib-Decitabine Intensified Conditioning Regimen for AML: A Randomized Trial

Ruxolitinib and Decitabine-Enhanced Conditioning Versus Modified Bu/Cy or BuF Conditioning for the Impact on Relapse of Acute Myeloid Leukemia in First Complete Remission (CR1)After Allogeneic Hematopoietic Stem Cell Transplantation: A Multicenter, Prospective Randomized Controlled Trial

This study aims to determine whether the recurrence rate of high-risk acute myeloid leukemia CR1 patients who received allogeneic hematopoietic stem cell transplantation with the Ruxolitinib, Decitabine combined with Bu/Cy or BuF intensive pretreatment regimen is reduced compared with the traditional Bu/Cy or BuFpretreatment regimen.

Allogeneic hematopoietic stem cell transplantation is the only radical treatment for high-risk acute myeloid leukemia (AML), but the traditional Bu/Cy pretreatment regimen is highly toxic and has a high recurrence rate after transplantation (the long-term survival rate is only 10-30%). Although the existing improved regimens such as sequential chemotherapy can reduce the leukemia burden, they lead to prolonged myelosuppression time (17-39 days) and a non-relapse mortality rate as high as 17.2%. There is an urgent need to develop new pretreatment regimens that have both strong anti-leukemia effects and low toxicity.

Studies have found that the JAK-STAT signaling pathway is generally abnormally activated in hematological tumors such as AML. The objective response rate of Ruxolitinib (a JAK1/2 inhibitor) as a monotherapy for relapsed/refractory leukemia reached 45%. When combined with the demethylated drug decitabine, it can synergistically inhibit leukemia cells. Clinical data show that decitabine reduces the recurrence rate after transplantation by 20% (15.0% vs 38.3%), and the combination of the two has good safety. The main adverse reaction is grade 1-2 hematological toxicity.

Our center innovatively proposed the Rux-Dec-mBu/Cy or BuF combined regimen: integrating Ruxolitinib (step-based dose reduction) and decitabine (20mg/m²/d) on the basis of the classic Bu/Cy or BuF. Previous single-arm studies have shown that the one-year recurrence rate of CR1 patients is 0%, and the incidence of toxicity above grade 3 is less than 11%. This study intends to conduct a multicenter randomized controlled trial to verify the superiority of this regimen in reducing recurrence after transplantation in patients with high-risk AML CR1. Its core advantage lies in simultaneously achieving anti-leukemia enhancement (through JAK-STAT targeting and epigenetic regulation) and controllable toxicity (The median grain deficiency time was shortened to 14 days).

Inclusion Criteria:

• 1) Acute myeloid leukemia with indications for allogeneic hematopoietic stem cell transplantation, CR1 2) Have HLA-matched sibling donors or haploidentical donors or ≥8/10 HLA-matched unrelated donors 3) The patients' ages range from 12 to 64 years old 4) Liver function: ALT and AST≤2.5 times the upper limit of normal values, bilirubin ≤2 times the upper limit of normal values 5) Renal function: Creatinine ≤ the upper limit of the normal value 6) There are no uncontrollable infections or serious mental and psychological disorders 7) Sign the informed consent form.

Exclusion Criteria:

• 1. Patients with acute promyelocytic leukemia (M3) 2. One of the donor and recipient is pregnant 3. Suffering from mental illness or other conditions that prevent one from following the plan.