Tafasitamab

Tafasitamab is a humanized, CD19-directed cytolytic monoclonal antibody intended for the treatment of B-cell malignancies. It is produced using recombinant DNA technology in Chinese hamster ovary cells, and contains an IgG1/2 hybrid Fc-domain which has been modified with 2 amino acid substitutions to enhance its cytotoxicity relative to non-engineered anti-CD19 antibodies.

The CD19 surface protein is highly expressed on the surface of B-cells, where it appears to play a role in enhancing B-cell receptor signaling. Its relative ubiquity across different stages of B-cell development, including pre-B and mature B-lymphocytes, as well as its presence in several B-cell malignancies (e.g. chronic lymphocytic leukemia (CLL), small lymphocytic lymphoma (SLL), diffuse large B-cell lymphoma (DLBCL)) has made it a desirable target in the treatment these B-cell malignancies. Tafasatimab is designed to bind to and block the activity of the CD19 surface antigen, which ultimately results in the lysis of B-cells (both healthy and malignant).

Having previously received Breakthrough Therapy, Fast Track, and Orphan designations from the FDA, tafasatimab-cxix (Monjuvi®) received an accelerated approval on July 31st, 2020, for the treatment of relapsed or refractory DLBCL in adult patients who cannot receive autologous stem cell transplants. It must be used in combination with lenalidomide, as this combination results in greater efficacy as compared to either agent alone.

Tafasitamab is indicated, in combination with lenalidomide, for the treatment of adult patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) not otherwise specified whom are ineligible for autologous stem cell transplant (ASCT).