Risk Stratification and MRD-driven Maintenance for MM After ASCT

This study evaluates the maintenance strategy based on risk stratification and MRD status after stem cell transplantation. This is a single-arm, multicenter, prospective study. Participants who are R2-ISS 1,2 and MRD negative receive the single drug lenalidomide maintenance. In other circumstances, for example, patients who are R2-ISS 3 or 4 will receive daratumumab combined with lenalidomide regardless of MRD status, while patients with MRD positivity will also receive daratumumab plus lenalidomide maintenance.