IntroAllogeneic-HCT is recommended for AML patients (pts) in CR2, in CR1 with poor-risk cytogenetics, and should be considered for those in CR1 with intermediate-risk. Non-relapse mortality (NRM) and GVHD remain major causes of treatment failure. Ex vivo TCD can prevent GvHD but large case series have not been published. MethodsA retrospective chart review was conducted to evaluate 178 pts with AML in CR1 and CR2 undergoing TCD-HCT between 2001 and 2011. All pts received myeloablative-conditioning. The majority received ATG for graft rejection prophylaxis. Acute (A) and chronic(c) GVHD were assessed by standard criteria. No GVHD prophylaxis was administered post-transplant. Soybean agglutination+sheepRBC rosetting (sRBCR) was used for BM TCD. CD34+ selection +/- sRBCR was used for PBSC TCD. Pt characteristics were compared using Pearson's chi-squared and Fisher's exact tests. Prognostic factors relating to overall survival (OS) and DFS, including age, gender, leukemia etiology, cytogenetic-risk group, donor-type, TCD-method, conditioning-regimen, HLA match grade, HCT-specific comorbidity index and immune reconstitution were evaluated using log-rank test statistics. Differences in cumulative incidence (CI) rates were evaluated using Gray's test. Cox proportional-hazards regression was used to further adjust for pt risk factors for OS and DFS. ResultsPt characteristics and outcomes are summarized in Tables 1 and 2. Median follow-up of survivors is 52 mo (12-134). 177 pts engrafted. One died pre-engraftment, 7 developed late graft-failure (GF), and 3 are alive after a 2nd HCT. One yr incidence of aGVHD was low (grade 2-4 13%, 3-4 3%). Only 1 pt developed cGVHD by NIH consensus criteria. Univariate association between CR status (1 vs 2), OS and DFS was not statistically significant (p=0.17 and 0.16, respectively). After adjusting for HLA status, age, sex, cytogenetic risk, and regimen, CR2 pts had an increased risk of death (HR: 1.90 (1.14-3.16), p= 0.014). In CR1 pts, cytogenetics was associated with relapse incidence (p=0.003) and was highest in patients with adverse cytogenetics (31%, 95%CI 16-48) and <10% in intermediate I-II risk pts. Overall CI relapse at 1 and 2 yrs was 13% and 16%, respectively. Causes of death were: relapse (n=29), infection (n=25), GVHD (n=7), organ toxicities (n=5), GF (n=2) and other (n=7).Female gender was significantly associated with decreased OS and DFS (p<0.002 and 0.003, respectively). Two yr estimates of OS and DFS in females vs males was 51% vs. 71% and 49% vs. 69%, respectively. These differences were due to a higher NRM in females receiving the chemotherapy based regimen (p<0.001). Gender difference was not observed in pts receiving TBI-based regimens (p=0.599). This difference persisted after adjusting for other common prognostic factors in a multivariate model. For the entire group, 2yr OS and DFS was 67% and 62%, respectively. For CR1 pts, 2 yr OS and DFS was 70% and 64%, respectively (Fig.1). ConclusionThese results support the use of TCD HCT in AML pts in CR. Durable DFS and long-term OS can be achieved with low rates of GVHD without compromising the graft-vs-leukemia effect. [Display omitted] [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.