TECVAYLI 153 mg Injection TECVAYLI contains Teclistamab-cqyv, a bispecific T-cell engager (BiTE) antibody designed to bind simultaneously to B-cell maturation antigen (BCMA) on plasma cells/multiple myeloma cells and to CD3 on T-lymphocytes. This dual binding recruits T-cells directly to tumor cells, triggering T-cell activation, cytotoxicity, and targeted lysis of multiple myeloma cells. It is indicated for the treatment of adult patients with relapsed or refractory multiple myeloma who have received at least four prior lines of therapy, including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 monoclonal antibody.