BMT CTN 0901 enrolled patients with MDS (N=54) or AML (N=218) (median age of 55 years) who had < 5% marrow blasts by morphology prior to HCT. The most common RIC regimen was FluBu2 (81%) and the most common MAC regimen was FluBu4 (64%). The planned enrollment was 356 patients; however, accrual was stopped early (N=272) due to a marked imbalance of relapse rates. While MAC resulted in longer relapse-free survival (RFS) at 18 months, there were no survival differences between conditioning intensities (Scott BL et al, JCO 2017). Data on all enrolled patients reported to the CIBMTR were used to supplement clinical trial outcomes beyond 18 months. Here we present an updated clinical trial analysis with a median follow up of 50 months.

Overall survival (OS) at 4 years was 65% and 49% for MAC and RIC (p=0.02), respectively. In multivariate analysis of overall mortality, the hazard ratio (HR) for death was 1.54 (95% Confidence Interval [CI] 1.07-2.20, p=0.02) for RIC compared to MAC. Other risk factors for mortality were protocol-defined high risk disease (HR 1.77) and age of ≥50 ys (HR 2.20). RFS rates at 4 years was 58% and 34% for MAC and RIC (p<0.001); the corresponding HR was 2.06 (95% CI 1.48-2.85, p<0.001) for RIC vs. MAC. Cumulative incidences of transplant-related mortality and relapse are shown in the figure. Subset analysis of MDS patients (n=54) were directionally similar to the overall analysis but not statistically significant, likely due to limited power. Post-HCT relapse survival among patients with AML was 24% and 26% for MAC and RIC (p=0.87) 3 years after leukemia relapse, respectively.

Long term follow up of MAvRIC showed longer survival for MAC recipients. Thus, this trial confirms the importance of intensity for HCT; for patients eligible for either intensity regimen, MAC is the superior choice.

BMT CTN 0901招募了MDS（N = 54）或AML（N = 218）（中位年龄为55岁）的患者，这些患者的形态学特征在HCT之前小于5％。最常见的RIC方案是FluBu2（81％），最常见的MAC方案是FluBu4（64％）。计划的招募人数为356名患者；但是，由于复发率明显失衡，应计提早停止（N = 272）。尽管MAC导致18个月的无复发生存期更长（RFS），但调节强度之间的生存率没有差异（Scott BL等人，JCO 2017）。向CIBMTR报告的所有入组患者的数据均用于补充18个月以上的临床试验结果。在这里，我们提供了更新的临床试验分析，中位随访时间为50个月。

MAC和RIC在4年时的总生存率（OS）分别为65％和49％（p = 0.02）。在总体死亡率的多变量分析中，与MAC相比，RIC的死亡风险比（HR）为1.54（95％置信区间[CI] 1.07-2.20，p = 0.02）。死亡率的其他危险因素是协议定义的高危疾病（HR 1.77）和年龄≥50ys（HR 2.20）。MAC和RIC在4年时的RFS率为58％和34％（p <0.001）；RIC与MAC对应的HR为2.06（95％CI 1.48-2.85，p <0.001）。图中显示了与移植相关的死亡率和复发的累积发生率。MDS患者的亚组分析（n = 54）在方向上与总体分析相似，但无统计学意义，可能是由于能力有限。AML患者HCT后的复发生存率分别为MAC和RIC的24％和26％（p = 0。

MAvRIC的长期随访显示，MAC接受者的生存期更长。因此，该试验证实了强度对于HCT的重要性。对于符合两种强度方案的患者，MAC是首选。