AK138D1

AK138D1 is an investigational HER3-targeted antibody-drug conjugate (ADC) developed by Akeso for the treatment of advanced solid tumors. It consists of a fully humanized anti-HER3 IgG1 antibody (patritumab) conjugated to the topoisomerase I inhibitor DXd via a cleavable MC-AAA linker. Upon binding to HER3 on tumor cells, AK138D1 is internalized, and the linker is cleaved intracellularly to release DXd, which induces DNA damage and apoptosis in cancer cells. The drug is currently being evaluated in a Phase I clinical trial for safety, tolerability, pharmacokinetics, immunogenicity, and preliminary efficacy in patients with advanced malignancies[1][5][6].