Antibody-urease conjugates having therapeutic utility are provided. More specifically, described herein are anti-VEGFR-2 antibody-urease conjugates for the treatment of solid tumors. A conjugate comprising an anti-VEGFR-2 antibody moiety conjugated to a urease moiety is described. Compositions and methods are also described for the treatment of VEGFR-2 dependent tumors, incorporating the antibody-urease conjugates described herein.