Ofatumumab Overview

Introduction of Ofatumumab

Ofatumumab, also known as HuMax-CD20, is an IgG1ĸ type fully human monoclonal antibody directed against CD20 antigen that expressed on normal B lymphocytes (pre-B- to mature B-lymphocyte) and on B-cell CLL. The molecular weight of ofatumumab is approximately 149 kDa. This drug was developed by Novartis Pharma AG and was designed for the treatment of chronic lymphocytic leukemia (CLL). In 2009, ofatumumab was approved by the U.S. Food and Drug Administration (FDA) for the treatment of chronic lymphocytic leukemia that is refractory to fludarabine and Arzerra. Ofatumumab was also conditional approved by Health Canada on August 2012, and by European Medicines Agency on April 19, 2010 for the treatment of chronic lymphocytic leukemia. In addition, this drug also received Therapeutic Goods Administration (TGA) approval and Japan Medical Devices Evaluation Center approval in 2013. In addition to CLL, ofatumumab also has also shown potential in treating follicular lymphoma, diffuse large B cell lymphoma, rheumatoid arthritis and relapsing remitting multiple sclerosis.

Mechanism of Action Ofatumumab

Ofatumumab is the active substance of Arzerra and has been designed to attach to a protein called CD20. Ofatumumab was found to inhibit the early-stage B lymphocyte activation. Thus, Ofatumumab became 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. Ofatumumab was designed to bind specifically to both the small and large extracellular loops of the CD20 molecule. Upon administration, the Fab domain of ofatumumab binds to the CD20 molecule and the Fc domain mediates immune effector functions. Binding of ofatumumab to CD20 stimulates the body’s immune system to attack the cancerous B-cells, helping to control the disease. In addition, by attaching to CD20, ofatumumab also could induce recruitment and activation of the complement pathway at the cell surface, leading to complement-dependent cytotoxicity and resultant lysis of tumour cells, and induce cell death through antibody-dependent cell-mediated cytotoxicity.

Fig.1 Mechanism of action of Ofatumumab

Table 1. Clinical Projects of Ofatumumab *

Table 2. Approved Drugs of Ofatumumab**

INN (trade name)	Therapeutic area	Dose	Strength	Route	Company	Marketing start	Market
Arzerra	Chronic lymphocytic leukemia	Injection	100mg /5ml	Intravenous Infusion	Glaxo Grp Ltd	October 26, 2009
Arzerra	Chronic lymphocytic leukaemia	Concentrate for solution	20 mg / ml	Intravenous infusion	Novartis Europharm Ltd	April 19, 2010
Arzerra	Recurrent or refractory CD20 positive chronic lymphocytic leukemia	Concentrate for solution	50ml/vial	Intravenous infusion	Novartis Pharma Co., Ltd.	25th March,  2013
Arzerra	Chronic lymphocytic leukaemia	Solution	100 mg / 5 ml	Intravenous infusion	Novartis Pharmaceuticals Canada Inc	August 13, 2012
Arzerra	Chronic lymphocytic leukaemia	Solution	1000 mg / 50 ml	Intravenous infusion	Novartis Pharmaceuticals Canada Inc	August 13, 2012
Arzerra	Chronic lymphocytic leukaemia	Injection	20 mg/mL	Intravenous infusion	Novartis Pharmaceuticals Australia Pty Ltd	February 11, 2013

What We Provide

Therapeutic Antibody

Ofatumumab

We provide high-quality Ofatumumab for use in WB, FC, IP, ELISA, Neut, FuncS, IF and most other immunological methods. For lab research use only, not for diagnostic, therapeutic or any in vivo human use.

Reference
* The table was excerpted from the following website
https://clinicaltrials.gov/ct2/results?term=Ofatumumab

** Information presented in the table were collected from the following website:
https://search.tga.gov.au/s/search.html?collection=tga-websites-web&query=Ofatumumab
https://www.ema.europa.eu/en/medicines/human/EPAR/arzerra

For research use only. Not intended for any clinical use.