Polatuzumab Vedotin: First Global Approval

Polatuzumab vedotin (polatuzumab vedotin-piiq; Polivy™) is an antibody–drug conjugate comprising a monoclonal antibody against CD79b (a B cell receptor component) covalently conjugated to the anti-mitotic cytotoxic agent monomethyl auristatin (MMAE) via a cleavable linker. After binding to CD79b on the B-cell surface, polatuzumab vedotin is internalized and the linker is cleaved, releasing MMAE into the cell, where it inhibits division and induces apoptosis. Polatuzumab vedotin is being developed by Genentech (a subsidiary of Roche) for the treatment of haematological malignancies. In June 2019, the US FDA granted accelerated approval to polatuzumab vedotin, in combination with bendamustine plus rituximab, for the treatment of adults with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) who have received at least two prior therapies. Use of the compound in combination with bendamustine plus rituximab is also under regulatory review for relapsed/refractory DLBCL in the EU and is in ongoing phase 1b/2 development in this setting or relapsed/refractory follicular lymphoma (FL) in several countries. Various other polatuzumab vedotin combination therapy regimens are also in phase 1b/2 development for relapsed/refractory non-Hodgkin lymphoma (NHL) [including DLBCL and FL] or in phase 2 or 3 development for previously untreated DLBCL, while polatuzumab vedotin monotherapy has been in phase 1 development for relapsed/refractory B-cell NHL in Japan. This article summarizes the milestones in the development of polatuzumab vedotin leading to this first approval for its use in combination with bendamustine plus rituximab for relapsed/refractory DLBCL.