Use of anti-HER2 antibody-drug conjugate in treating urothelial carcinoma

A method for treating urothelial carcinoma, comprising

• administering an antibody-drug conjugate (ADC) to a subject in need thereof, wherein the antibody-drug conjugate is an anti-HER2 antibody or a functional fragment thereof coupled to a cytotoxic molecule;
• wherein the ADC is represented by formula Ab-(L-U)n, wherein Ab is the antibody or the functional fragment thereof, L is a linker, U is a conjugated cytotoxic molecule, and n is an integer from 1 to 8, representing the number of therapeutic agent molecules bound to the antibody;
• wherein the anti-HER2 antibody or the functional fragment thereof comprises a heavy chain variable region and a light chain variable region, wherein (i) the heavy chain variable region comprises three CDRs, wherein the amino acid sequences of the CDRs are respectively set forth in SEQ ID NO:
• 1, 2 and 3, and the light chain variable region comprises three CDRs, wherein the amino acid sequences of the CDRs are respectively set forth in SEQ ID NO:
• 4, 5 and 6;
• wherein the linker L is a maleimidocaproyl valine citrulline p-amino-benzyl (mc-vc-pAB) linker;
• and
• wherein the conjugated cytotoxic molecule U is MMAE;
• and
• wherein administration of the ADC to the subject results in a partial remission (PR) or stable disease (SD).