NKTR-255 is a cytokine that is designed to regulate T and natural killer cell activation, proliferation and promote their anti-tumor effects.~This is a Phase 1, open-label, multi-center, dose escalation, dose expansion, safety follow-up, and survival follow-up of NKTR-255 as a single agent and NKTR-255 in combination with DARZALEX FASPRO TM or rituximab. Study treatment is defined as any investigational treatment(s) or marketed product(s), intended to be administered to a study patient according to the study enrollment.~Part 1 will enroll relapsed/refractory multiple myeloma (MM) and Non-Hodgkin's Lymphoma (NHL) patients. In Part 2, Cohort A will enroll NHL patients who have progressed on a chimeric antigen receptor T-cell (CAR-T) product, Cohort B will enroll MM patients who previously received daratumumab and other anti-CD38 therapies to receive NKTR-255 alone and/or in combination with daratumumab, and Cohort C will enroll indolent Non-Hodgkin's Lymphoma (iNHL) patients who previously received rituximab and other therapies to receive NKTR-255 alone and/or in combination with rituximab.
Patients will receive intravenous (IV) NKTR-255 in 21 or 28 day treatment cycles. During the Part 1 dose escalation portion of the trial, patients will either receive NKTR-255 as monotherapy, NKTR-255 administered as a doublet with daratumumab subcutaneous (DARZALEX FASPRO TM), or NKTR-255 administered as a doublet with rituximab. After determination of the recommended Phase 2 dose (RP2D) of NKTR-255, NKTR-255 will be evaluated in Part 2. During the Part 2 dose expansion portion of the trial, patients will either receive NKTR-255 as monotherapy, NKTR-255 administered as a doublet with daratumumab subcutaneous (DARZALEX FASPRO TM), or NKTR-255 administered as a doublet with rituximab.~This is a Phase 1 study to evaluate safety and tolerability of NKTR-255 alone and in combination with daratumumab or rituximab.