1D09C3 is a fully humanized anti-HLA-DR monoclonal antibody. It induces cell apoptosis (apoptosis) and death through a cascade of reactions, including reactive oxygen species (ROS) production, JNK activation, mitochondrial membrane depolarization, and the release of AIF from mitochondria. In xenograft models with JVM-2 cells and GRANTA-519 cells in mice, 1D09C3 demonstrated significant antitumor activity, improving overall survival and median survival time. This compound is applicable in cancer research, including studies on chronic lymphocytic leukemia (CLL).

1D09C3 at a concentration of 2.5 µg/mL for 24 hours significantly decreases cell count and viability in HLA-DR positive cell lines, but does not affect HLA-DR negative cell lines. It induces potent, time- and dose-dependent cell death in JVM-2 and GRANTA-519 cells at concentrations ranging from 0.1 to 10 µg/mL over 4 to 24 hours. Additionally, 1D09C3 at 10 µg/mL for 4 to 24 hours triggers apoptosis in these cells via a non-caspase dependent pathway, and the same concentration over 5 to 240 minutes leads to mitochondrial depolarization and ROS generation. Furthermore, 1D09C3 at 10 µg/mL for 0.5 to 4 hours induces cell death through JNK activation. At 2.5 µg/mL for 4 hours, it induces B-CLL cell death, and when used at 10 µg/mL for 48 hours, it reduces activated T cell numbers by 20% and both resting and active B cell numbers by 50%.

Administering 1D09C3 (0.01-6 mg/mouse, I.V.) significantly enhanced both the overall survival and median survival in mouse models xenografted with JVM-2 cells and GRANTA-519 cells.