A humanized monoclonal antibody directed against interleukin-13 (IL-13) with potential antineoplastic activity. Anti-IL-13 humanized monoclonal antibody TNX-650 binds to and blocks the activity of IL-13, which may result in the inhibition of Hodkin lympoma cell proliferation. IL-13 cytokine, an important mediator in allergic inflammation, may be an autocrine growth factor for Hodgkin lymphoma cells.