US Patent 8722047 Humanized anti-HLA-DR antibodies

The present invention concerns compositions and methods of use of humanized anti-HLA-DR antibodies. In preferred embodiments, the antibodies induce apoptosis and inhibit proliferation of lymphoma cells without inducing CDC or ADCC. In more preferred embodiments, the humanized anti-HLA-DR antibodies bind to the same epitope of HLA-DR as, or compete for binding to HLA-DR with, a murine L243 antibody. Most preferably, the humanized anti-HLA-DR antibody exhibits a higher affinity for HLA-DR than the parental murine antibody. The humanized HLA-DR antibody is of use for therapy of various diseases such as cancer, autoimmune disease or immune dysregulatory function, and is of particular use for therapy of B cell lymphomas and leukemias. In most preferred embodiments, the humanized anti-HLA-DR antibody is capable of inducing at least partial remission of lymphomas that are resistant to other B cell antibodies, such as rituximab.