| abstract |
The present invention relates to antibodies or fragments thereof that specifically bind FcγRIIB, particularly human FcγRIIB, more particularly the extracellular domain of FcγRIIB with greater affinity than said antibodies or fragments thereof bind FcγRIIA, particularly human FcγRIIA, and block the Fc binding site of FcγRIIB. The present invention also encompasses the use of an anti-FcγRIIB antibody or an antigen-binding fragment thereof, as a single agent therapy for the treatment, prevention, management, or amelioration of a cancer, preferably a B-cell malignancy, particularly, B-cell chronic lymphocytic leukemia or non-Hodgkin's lymphoma, an autoimmune disorder, an inflammatory disorder, an IgE-mediated allergic disorder, or one or more symptoms thereof. The present invention also encompasses the use of an anti-FcγRIIB antibody or an antigen-binding fragment thereof, in combination with other cancer therapies. The present invention provides pharmaceutical compositions comprising an anti-FcγRIIB antibody or an antigen-binding fragment thereof, in amounts effective to prevent, treat, manage, or ameliorate a cancer, such as a B-cell malignancy, an autoimmune disorder, an inflammatory disorder, an IgE-mediated allergic disorder, or one or more symptoms thereof. The invention further provides methods of enhancing the therapeutic effect of therapeutic antibodies by administering the antibodies of the invention to enhance the effector function of the therapeutic antibodies. The invention also provides methods of enhancing efficacy of a vaccine composition by administering the antibodies of the invention with a vaccine composition. The invention further provides methods of treating cancer and/or regulating immune complex-mediated cell activation by administering the antibodies of the invention to enhance an immune response. The invention also provides methods of breaking tolerance to an antigen by administering an antigen-antibody complex and an antibody of the invention. |