Introduction A meta-analysis of three large randomized trials has demonstrated that len maint prolongs progression free survival (PFS) and overall survival (OS) in pts with MM who have undergone ASCT. While len maint benefits pts with both high-risk and standard-risk cytogenetics, it does not appear to provide equal magnitude of benefit to patients with high-risk cytogenetics. We conducted a retrospective analysis comparing the outcomes of pts with MM who underwent ASCT at our institution and len maint compared to no maint. We further evaluated the impact of len maint on the two cytogenetic groups. Methods We performed a retrospective analysis of 1002 consecutive pts with newly diagnosed MM who underwent ASCT at The Ohio State University between 1992 through 2016. Data were collected regarding patient demographics, disease characteristics, therapy received including maint, and clinical outcomes. Pts were excluded from the analysis if they received len combination or other drug maint therapies. High-risk cytogenetics was defined as having t(4;14), t(14;16), gain 1q, or del17p. PFS and OS were estimated using Kaplan-Meier method. Log-rank test was used to compare PFS and OS between the groups and Cox proportional hazard models were used to estimate the hazard ratios (HR). Results Pt characteristics are listed in Table 1. 484 pts (53.3%) received no maint while 423 pts (46.7%) received len maint. 245 pts (24.4%) had high-risk cytogenetics while 561 pts (56%) had standard-risk cytogenetics with the remaining unknown. Both PFS and OS were significantly better in the len maint group compared to the no maint group (Figure 1). Adjusting for pts age at transplant, cytogenetic risk, pre-transplant and post-transplant disease status, and ISS staging, the superiority in PFS and OS remained statistically significant, HR=0.50 (95% CI: 0.41-0.62), p Conclusion Consistent with previously published data, our results demonstrate an improvement in outcomes in MM pts treated with len maint following ASCT compared to no maint regardless of cytogenetic risk group. Larger studies are needed to assess the individual benefit obtained with len maint with each high-risk cytogenetic abnormality. Several trials incorporating newer drugs with novel mechanisms of action are currently being done that could further optimize maint therapy and lead to better outcomes in high-risk group.