Monoclonal antibodies are drugs that recognise, target and stick to particular proteins on the surface of cancer cells. They can stimulate the body’s immune system to destroy these cells.


A monoclonal antibody called rituximab is used to treat B cell lymphomas like WM. It targets the protein CD20 found on B-lymphocytes and is given as a drip into a vein (infusion). Rituximab may be given with chemotherapy and/or steroids and the combination then has an ‘R’ added (e.g R-Bendamustine). It may cause allergic reactions at the time of the infusion (and rarely afterwards), the first infusion is given over six hours to try and limit this reaction. Subsequent infusions can usually be given over 60-90 minutes.

Ofatumumab (Arzerra®) and obinutuzumab (GA101)

Ofatumumab (Arzerra®) and obinutuzumab (GA101) are newer anti-CD20 monoclonal antibodies that also appear effective in indolent lymphomas including WM. However, they are not easily obtainable outside of clinical trials.

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