MajesTEC-1

The study will be conducted in 2 parts, separately for IV and SC administration: dose escalation (Part 1) and dose expansion (Part 2). It will evaluate safety, tolerability, pharmacokinetics and preliminary antitumor activity of Teclistamab administered to adult participants with relapsed or refractory multiple myeloma. The overall safety of the study drug will be assessed by physical examinations, Eastern Cooperative Oncology Group performance status, laboratory tests, vital signs, electrocardiograms, adverse event monitoring, and concomitant medication usage. Disease evaluations will include peripheral blood and bone marrow assessments at screening (performed within 28 days) and to confirm stringent complete response (sCR), complete response (CR), or relapse from CR. The end of study (study completion) is defined as 2 years after the last participant in Part 3 has received his or her initial dose of teclistamab. Study record NCT04557098 is Phase 2 part of this study and study record NCT03145181 is Phase 1 part of this study.