Thursday, April 25, 2019
Serum presence of BCMA prevents ADC Targeting
The researchers at Oncotherapeutics have discovered something very interesting about the BCMA targeting biologic therapies in multiple myeloma patients. This paper documents the presence of BCMA antigen in serum which effectively acts as a competitive inhibitor for the antibody attempting to reach to tumor cells.
The levels of this inhibition were high enough to interfere with tumor binding and to inhibit the effectiveness of the therapy.
This is interesting as it adds another level of complexity to the choice of antigen targeting when developing a biologic. Is it possible that a rapid internalization would be correlated with a rapid explusion and presence of inhibitory levels in the serum? Or is this likely a non-consequential side effect which should not cause much concern?