KK2845_5

KK2845_5 is an investigational antibody-drug conjugate (ADC) developed by Kyowa Kirin for the treatment of relapsed or refractory acute myeloid leukemia (AML). It comprises a non-fucosylated, fully human IgG1 monoclonal antibody targeting T-cell immunoglobulin mucin-3 (TIM-3), which is selectively expressed on leukemic stem cells and blasts. The antibody is conjugated via a protease-cleavable valine-alanine linker to a pyrrolobenzodiazepine (PBD) dimer payload (SG3199, also referred to as tesirine in its linker-payload form). KK2845_5 exerts its therapeutic effect through two primary mechanisms: the delivery of the PBD dimer, which induces lethal DNA cross-linking, and the induction of antibody-dependent cellular cytotoxicity (ADCC), which is enhanced by the non-fucosylated antibody backbone. The drug is currently being evaluated in a Phase I dose-escalation clinical trial (NCT06812104).