Prognostic impact of MRD status before and during lenalidomide maintenance after autoSCT for multiple myeloma

Minimal residual disease (MRD) status can predict outcomes in patients with multiple myeloma (MM), but limited data are available on the prognostic impact of MRD status when assessed at serial time points in the context of maintenance therapy after autologous stem-cell transplant (ASCT). The phase 3 Myeloma XI trial randomized MM patients three months after ASCT to lenalidomide maintenance or no maintenance. MRD status was assessed before randomization and six months later. On both time points MRD status was a powerful predictor of progression-free and overall survival. Sustained MRD negativity on both time points and conversion from MRD positivity to MRD negativity were associated with longest PFS and OS. Patients randomly assigned to lenalidomide maintenance were more likely to convert from being MRD-positive to MRD-negative six months later. High-risk molecular features had an adverse effect on PFS and OS even for those patients achieving MRD-negative status.