Patients with relapsed/refractory multiple myeloma proceeding with chimeric antigen receptor (CAR) T-cell therapy or bispecific antibodies (BsAb) may need bridging therapy to realize their benefits. We evaluated the efficacy and safety of rapid, peripheral, high-dose cyclophosphamide (TurboCy) in 15 patients intending to proceed with CAR T-cell therapy, BsAbs, or long-term regimens. The overall response rate was 80% and the clinical benefit rate was 100% in a heavily pretreated high-risk cohort. Cytopenias were common but no deaths occurred during bridging. All patients proceeded to their next line of intended therapy. TurboCy is an effective and safe bridging strategy.