Type Whole antibody Target CD20 AHFS/Drugs.com Monograph | Source Human Trade names Arzerra MedlinePlus a610009 | |
Ofatumumab (trade name Arzerra, also known as HuMax-CD20) is a fully human monoclonal antibody (for the CD20 protein) which appears to inhibit early-stage B lymphocyte activation. It is FDA approved for treating chronic lymphocytic leukemia that is refractory to fludarabine and alemtuzumab (Campath) and has also shown potential in treating Follicular non-Hodgkin’s lymphoma, Diffuse large B cell lymphoma, rheumatoid arthritis and relapsing remitting multiple sclerosis. Ofatumumab has also received conditional approval in Europe for the treatment of refractory chronic lymphocytic leukemia. This makes ofatumumab the first marketing application for an antibody produced by Genmab, as well as the first human monoclonal antibody which targets the CD20 molecule that will be available for patients with refractory CLL.
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Medical uses
Its only indication that has received regulatory approval is Chronic lymphocytic leukaemia (CLL).
FDA Approval
It first received FDA approval on April 17, 2014, for use in combination with chlorambucil, for the treatment of previously untreated patients with CLL for whom fludarabine-based therapy is considered inappropriate MHRA approval on the 19th of April 2010,
EMA Approval
EMA approval on the 14th of June 2010 and Health Canada approval on the 13th of August 2012.
Adverse effects
Adverse effects by frequency:
Very common (>10% frequency):
Common (1-10% frequency):'
Uncommon (0.1-1% frequency):
Rare (<0.1% frequency):
Ofatumumab has received a black box warning regarding the potential for it to cause progressive multifocal leukoencephalopathy and Hepatitis B reactivation. Likewise it is also advised that doctors watch cautiously for small bowel obstruction, neutropenia, thrombocytopenia, infusion reactions or an increased risk for infection.
Contraindications
It is contraindicated in individuals that have hypersensitivity to ofatumumab or any of its excipients.
Interactions
No formal drug interaction studies have been conducted with ofatumumab. Although it is advised that patients are not administered live virus vaccines (e.g. the oral polio vaccine) while undergoing treatment with ofatumumab due to the compromised ability to fight the attenuated viruses seen in patients being treated with ofatumumab.
Mechanism
Ofatumumab is a humanised anti-CD20 monoclonal antibody whose epitope is distinct from that of rituximab. The CD20 antigen is expressed on solely B cell lymphocytes. Compared with rituximab, ofatumumab binds more tightly to CD20 with a slower off-rate. It causes cytotoxicity in the cells that express CD20 by means of complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC).
Clinical trials
Status of clinical trials of ofatumumab conducted by Genmab and GSK, as of late 2010.