A Study of TNB-383B in Subjects With Relapsed or Refractory Multiple Myeloma

Open to people ages 18 years and up

• Subjects with Relapsed/Refractory Multiple Myeloma.
• Subject has received three or more prior lines of therapy with exposure to a proteasome inhibitor (PI), an immunomodulatory imide (IMiD) and an anti-CD38 monoclonal antibody (e.g., daratumumab).
• Subject has Measurable Disease, defined as at least 1 of the following:
• Serum M-protein ≥ 0.5 g/dL (≥ 5 g/L)
• Urine M-protein ≥ 200 mg / 24h
• Serum free light chain (FLC) assay: Involved FLC level ≥ 10 mg/dl (≥ 100 mg/L) and an abnormal serum FLC ratio (< 0.26 or > 1.65).
• Subject has an Eastern Cooperative Oncology Group (ECOG) Performance Status of ≤ 2.
• Prior bone marrow transplant is acceptable if subject is > 12 weeks (autologous) or > 1 year (allogeneic) status-post transplantation
• Subject must have adequate bone marrow function, defined as:
• absolute neutrophil count (ANC) ≥ 1000/mm3;
• platelets ≥ 50,000/mm3;
• hemoglobin ≥ 8.0 g/dL.
• Subject must have an eGFR ≥ 30 mL/min as estimated by the MDRD formula.
• Subject must have total bilirubin ≤ 1.5 × upper limit of normal (ULN; except if the subject has a known diagnosis of Gilbert's syndrome, in which case bilirubin must be < 3 x ULN).
• Serum calcium (corrected for albumin) at or below the ULN range.

• Subject has ever received BCMA-targeted therapy. Subjects who have received targeted therapy against non-BCMA targets will not be excluded
• Subject has a history of central nervous system involvement by their myeloma.
• Subject has a history of ≥ Grade 3 peripheral neuropathy.
• Subject has a history of plasma cell leukemia, POEMS syndrome, or amyloidosis.
• Subject has received any therapy to treat cancer or undergone a major surgical procedure within 21 days, or within 5 half-lives of an anticancer drug, prior to the first dose of study treatment, whichever is shorter.
• Subject has a history of major cardiac abnormalities.
• Subject has a known active infection requiring parenteral anti-infective treatment