Inclusion Criteria:

Must have relapsed or refractory multiple myeloma (RRMM) after having received prior lines of anti-myeloma treatments, including being refractory to a proteasome inhibitor, immunomodulatory agent and an anti-CD38 monoclonal antibody
Measurable disease as defined by one of the following: abnormal serum or M-protein levels; abnormal serum free light chain (FLC) assay; ≥ 30% clonal plasma cells in the bone marrow aspirate or biopsy sample
Pulse oximetry ≥ 92% on room air
Eastern Cooperative Oncology Group (ECOG) performance of 0 – 2
Be willing and able to comply with the study schedule and all study requirements
Willing to follow contraception guidelines

Exclusion

Exclusion Criteria:

Prior systemic anti-tumor therapy or an investigational drug within 5 half-lives or 4 weeks of D1, whichever is shorter, preceding the first dose of study drug
Prior treatment with allogeneic hematopoietic stem cell transplantation within 6 months, has active graft versus host disease following transplant or currently receiving immunosuppressive therapy following transplant
Diagnosis of other malignancies if the malignancy required therapy in the last 3 years or is not in complete remission
Current history of CTCAE Grade 3 muscle paresis or ocular disorders that are Grade 3 or 2
Has any clinically significant low baseline lab results for hemoglobin, platelet counts, and neutrophil counts at screening
Abnormal INR or aPTT, unless on a stable dose of an anticoagulant
Has ≥ Grade 3 neuropathy or Grade 2 neuropathy with associated pain
Has any clinically significant baseline lab results for creatinine clearance, serum aspartate aminotransferase, alanine aminotransferase, total bilirubin
New York Heart Association Class > 2
Left ventricular ejection fraction < 40% Prolonged QTcF interval on a 12-lead electrocardiogram Has active COVID-19 infection, and not present with symptoms within 4 weeks of study drug Has an active bacterial, viral, or fungal infection Has known HIV or acquired immunodeficiency syndrome-related illness, acute or history of chronic hepatitis B or C Is currently pregnant or breast feeding or planning on either during the study Has any significant medical condition, abnormality, or psychiatric illness that would prevent study participation Has any additional clinical history that would place the patient at an unacceptable risk if the patient participates in the study