Source: Australian Department of Health
Polatuzumab vedotin is a cancer treatment.
Polatuzumab vedotin is a CD79b-targeted antibody-drug conjugate that preferentially delivers an anti-mitotic agent (monomethyl auristatin E, or MMAE) to B-cells, which results in the killing of malignant B-cells.
The polatuzumab vedotin molecule consists of MMAE covalently attached to a humanised immunoglobulin G1 (IgG1) monoclonal antibody via a cleavable linker. The monoclonal antibody binds with nanomolar affinity to CD79b, a cell surface component of the B cell receptor. CD79b expression is restricted to normal cells within the B-cell lineage (with the exception of plasma cells) and malignant B-cells; it is expressed in > 95% of diffuse large B-cell lymphoma (DLBCL). Upon binding CD79b, polatuzumab vedotin is internalised and the linker is cleaved by lysosomal proteases to enable intracellular delivery of MMAE. MMAE binds to microtubules and kills dividing cells by inhibiting cell division and inducing apoptosis.