Study to Assess Safety and Tolerability of OPN-6602 in Subjects With Relapsed and/or Refractory Multiple Myeloma

Inclusion Criteria:

• Confirmed diagnosis of multiple myeloma (MM)

• Relapsed or refractory to 3 or more different prior lines of therapy for MM thatincluded immunomodulatory agents, proteosome inhibitors, and anti-CD38 antibody andnot a candidate for or intolerant to established therapy known to provide clinicalbenefit

• Adequate hematologic, renal, liver, cardiac function

Exclusion Criteria:

• Monoclonal gammopathy of undetermined significance (MGUS), smoldering myeloma,Waldenström's macroglobulinemia, or IgM myeloma

• Active plasma cell leukemia

• Polyneuropathy, organomegaly, endocrinopathy, monoclonal protein and skin changes (POEMS syndrome)

• Prior Stevens Johnson syndrome

• Localized radiation therapy to disease site(s) within 2 weeks of the first dose

• Prior autologous peripheral stem cell transplant or prior autologous bone marrowtransplantation within <90 days of the first dose of study drug

• Prior allogeneic stem cell transplantation or solid organ transplantation within 12months of screening; subjects receiving immunosuppressive medication for activegraft vs host disease will be excluded.

• Prior chemotherapy, targeted anticancer or radiation therapy within 2 weeks prior tofirst dose of study drug

• Concomitant high-dose corticosteroids (except subjects on chronic steroids given fordisorders other than myeloma)

• Known central nervous system involvement by multiple myeloma

• Active known second malignancy with exception of adequately treated basal cellcarcinoma, squamous cell carcinoma of the skin, or in situ cervical cancer;adequately treated Stage 1 cancer from which the subject is currently in remissionand has been in remission for ≥2 years; low-risk prostate cancer with a Gleasonscore <7 and a PSA level <10 ng/mL; any other cancer from which the subject has beendisease-free for ≥3 years

• Ongoing systemic infection requiring parenteral treatment

• Poorly controlled Type 2 diabetes