Mitoxantrone Hydrochloride Liposome Injection in the Treatment of Relapsed/Refractory Multiple Myeloma

Dexamethasone 20 mg/d, on the same day of daratumumab injection; Mitoxantrone hydrochloride liposome injection: 20 mg/m2, d1; Daratumumab: 16 mg/Kg, once a week for the first 8 weeks; then changed to once every two weeks; Each cycle is 4 weeks long and the maximum number of cycles is 6.