NXC-201 (formerly HBI0101) Multiple Myeloma

Inclusion Criteria: * ≥18 years of age * Voluntarily signed informed consent form (ICF) * Eastern Cooperative Oncology Group (ECOG) performance status 0 - 2 * Diagnosis of MM with relapsed or refractory disease and have had at least 3 different prior lines of therapy including proteasome inhibitor, immunomodulatory therapy and at least one antibody therapy. * Subjects must have measurable disease, including at least one of the criteria below: * Serum M-protein greater or equal to 0.5 g/dL * Urine M-protein greater or equal to 200 mg/24 h * Serum free light chain (FLC) assay: involved FLC level greater or equal to 5 mg/dL (50 mg/L) provided serum FLC ratio is abnormal * A biopsy-proven evaluable plasmacytoma * Bone marrow plasma cells \> 20% of total bone marrow cells * Non secretory patient will be allowed provided they have measurable disease by PET-CT or bone marrow aspiration, as designated. * Women of child-bearing potential (WCBP), must have a negative serum pregnancy test prior to treatment. All sexually active WCBP and all sexually active male subjects must agree to use effective methods of birth control throughout the study * Recovery to ≤Grade 2 or baseline of any non-hematologic toxicities due to prior treatments, excluding alopecia and Grade 3 neuropathy * Ability and willingness to adhere to the study visit schedule and all protocol requirements