ERBB2 and breast cancer: Disitamab vedotin (RC48-ADC), the pioneering HER2-targeted ADC in China, comprises a novel humanized anti-HER2 monoclonal antibody covalently linked to the microtubule inhibitor monomethyl auristatin E (MMAE) via a cleavable linker.23 It has obtained regulatory approval for the treatment of HER2 IHC2+ or IHC3+ gastric cancer and urothelial cancer in China.24-26 The indication for BC is also under review for approval.