atezolizumab + ladiratuzumab vedotin

**Atezolizumab + ladiratuzumab vedotin** is a combination therapy under investigation for metastatic triple-negative breast cancer (mTNBC). Atezolizumab is a monoclonal antibody targeting PD-L1, thereby releasing immune inhibition and enabling T-cell activation. Ladiratuzumab vedotin (SGN-LIV1A) is an antibody-drug conjugate targeting the zinc transporter LIV-1 (SLC39A6), a protein highly expressed in various breast cancers, especially triple-negative variants. Ladiratuzumab vedotin consists of a humanized IgG1 monoclonal antibody linked via a protease-cleavable linker to the microtubule inhibitor monomethyl auristatin E (MMAE). Upon binding to cell-surface LIV-1, the conjugate is internalized, and MMAE is released to induce mitotic arrest and cell death. The combination is hypothesized to provide synergistic antitumor activity through both immune activation (PD-L1 inhibition) and direct tumor cell killing (antibody-drug conjugate action) and is being studied in phase Ib/II clinical trials in mTNBC patients who have not been previously treated with immunotherapy[1][3][5][7].