- Belimumab is a fully human IgG1 anti BLyS monoclonal. By blocking circulating BLyS it
avoids activation of BCMA, BAFF-R or TACI.
- Atacicept is a recombinant fusion protein built with the extracellular ligand binding portion of TACI. It blocks activation of TACI by APRIL or BLyS.
- BR3-Fc is a recombinant fusion protein built with the extracellular ligand binding portion of BR3. It blocks activation of BAFF-R by BLyS.
- Rituximab and other anti CD20 monoclonals destroy B lymphocytes bearing this antigen.
Abbreviations : APRIL a proliferation inducing ligand; BAFF B cell activation factor of the TNF family (also known as BLyS); BAFF-R receptor for BAFF; Bcl-2 B cell lymphoma gene 2; BCMA B cell maturation antigen; BLyS B lymphocyte stimulator;
BR3 BAFF receptor 3 (also known as BAFF-R); NFk B nuclear factor kappa B; TACI transmembrane activator and calcium modulator and cyclophylin ligand interactor
With Belimumab and Atacicept B cell depletion seems less profound and less longlasting than with Rituximab. But this is only a preliminary impression after the June 2007 EULAR (European League Against Rheumatism).
- Alemtuzumab, humanized anti CD52, highly expressed on T & B lymphocytes, was approved in 2001 (FDA) for treatment of chronic lymphocytic leukemia, It shows long lasting activity in multiple sclerosis.