A Study of CS1-targeted CAR-T Cells Therapy for Relapsed Multiple Myeloma After BCMA CAR-T Cells Therapy

Inclusion Criteria:

1. Histologically confirmed diagnosis of CS1+ multiple myeloma (MM)：

   1. Patients with MM relapsed after BCMA CAR-T therapy;Or MM with positive CS1 expression and negative BCMA expression;
   2. Relapsed after hematopoietic stem cell transplantation;
   3. Cases with recurrent positive minimal residual disease;
   4. Extramedullary leision which is hard to be eradicated by chemotherapy or radiotherapy.
2. Anticipated survival time more than 12 weeks;
3. Male or female aged 30-75 years;
4. Those who voluntarily participated in this trial and provided informed consent.

Exclusion Criteria:

Subjects with any of the following exclusion criteria were not eligible for this trial:

1. History of craniocerebral trauma, conscious disturbance, epilepsy, cerebrovascular ischemia, and cerebrovascular hemorrhagicdiseases;
2. Electrocardiogram shows prolonged QT interval, severe heart diseases such as severe arrhythmia in the past;
3. Pregnant (or lactating) women;
4. Patients with severe active infections (excluding simple urinary tract infectionand bacterial pharyngitis);
5. Active infection of hepatitis B virus or hepatitis C virus;
6. Concurrent therapy with systemic steroids within 2 weeks prior to screening, except for the patients recently or currently receiving inhaled steroids;
7. Previously treated with any CAR-T cell product or other genetically-modified T cell therapies;
8. Creatinine\>2.5mg/dl, or ALT / AST \> 3 times of normal amounts, or bilirubin\>2.0 mg/dl;
9. Other uncontrolled diseases that were not suitable for this trial;
10. Patients with HIV infection;
11. Any situations that the investigator believes may increase the risk of patients or interfere with the results of study.