Inclusion Criteria

Inclusion criteria

1. Diagnosis of MM requiring systemic therapy

2. Age ≥ 18 years

3. ECOG performance status (0-2)

4. Life expectancy > 3 months

5. Relapsed or refractory to two or more different prior therapies

6. Signed Informed consent

Exclusion criteria

1. Plasma cell leukemia

2. Known amyloidosis

3. Patients who previously have received an allogeneic stem cell transplant and receive
or have received immunosuppressive therapy within the last three months

or

Patients who previously have received an allogeneic stem cell transplant and have
signs of acute or chronic graft-versus-host disease

4. Sensory or motor neuropathy ≥ grade 3

5. Past or current malignancy

6. Chronic or ongoing active infectious disease

7. Clinically significant cardiac disease

8. Significant concurrent, uncontrolled medical condition including, but not limited to,
renal (except related to MM), hepatic, hematological except MM, gastrointestinal,
endocrine, pulmonary, neurological, cerebral or psychiatric disease

9. A baseline QT interval as corrected by Fridericia's formula > 470 msec for female
patients or > 450 msec for male patients or a complete left bundle branch block
(defined as a QRS interval≥ 120 msec in left bundle branch block form)

10. Hypokalemia

11. Clinical signs of meningeal involvement of MM

12. Known severe chronic obstructive pulmonary disease or asthma defined as FEV1< 60% of
expected

13. History of significant cerebrovascular disease

14. Known Human Immunodeficiency Virus seropositivity

15. Positive serology for hepatitis B

16. Screening laboratory values

17. Concomitant corticosteroid

18. Other chemotherapy that is or may be active against myeloma within 3 weeks prior to
Visit 1 (Part 2)

19. Known hypersensitivity to components of the investigational product or severe
allergic or anaphylactic reactions to humanized products

20. Patients who have received treatment with any nonmarket drug substance within 4 weeks
before Screening (Part 1: Visit 1; Part 2: Visit 0)

21. Current participation in any other interventional clinical trial

22. Patients known or suspected of not being able to comply with a trial protocol (eg,
due to alcoholism, drug dependency, or psychological disorder)

23. Breastfeeding women or women with a positive pregnancy test at Screening

24. Women of childbearing potential not willing to use adequate contraception, defined as
hormonal birth control or intrauterine device, during the trial and for 1 year after
the last dose of daratumumab. For patients in the US, the use of a double-barrier
method is also considered adequate