Rituximab belongs to a group of cancer drugs known as monoclonal antibodies. These drugs are sometimes called targeted (biological) therapies. They work by ‘targeting’ specific proteins (receptors) on the surface of cells.
Rituximab targets a protein called CD20. This is found on the surface of white blood cells called B-lymphocytes (B-cells).
CD20 is found on normal B-cells. It is also found on most of the abnormal (malignant) B-cells that occur in many types of NHL, and some of the abnormal B-cells that occur in CLL.
Rituximab locks on to CD20. It then triggers the body’s immune system to attack the cells and destroy them. Rituximab destroys both abnormal and normal B-cells. Once treatment is over, the body can replace the normal B-cells.