Adalimumab

Adalimumab is an injectable prescription drug used to treat diseases of the immune system; it is marketed by Abbot as Humira. It is one of three drugs that work by inhibiting the potent inflammatory molecule tumor necrosis factor-alpha (TNF-alpha); the others are etanercept (Enbrel) and infliximab (Remicade). Like etanercept and infliximab, adalimumab is a large protein molecule made with recombinant DNA technology. Adalimumab is a monoclonal antibody of the IgG1 subtype that has been "humanized", meaning that all of its components are derived from human molecules.

Uses

Adalimumab is approved for use in several diseases and shows promise in several others for which it is not approved ("off-label" indications). The approved indications include:

• Rheumatoid arthritis
• Juvenile idiopathic arthritis
• Psoriatic arthritis
• Ankylosing spondylitis
• Crohn disease
• Plaque psoriasis

How Adalimumab Is Taken

Adalimumab is sold as a sterile solution to be injected subcutaneously; a typical dose would be 0.8 mL of solution containing 40 mg of the drug.

How It Works

Adalimumab works by binding to and thereby inactivating TNF-alpha.

Benefits

In Crohn disease, adalimumab is comparable to infliximab and etanercept because the three drugs have a common mechanism of action. Adalimumab offers the advantage of subcutaneous administration, meaning that patients can keep the drug at home and inject it themselves—drugs that must be given by vein take longer to infuse and require a hospital or outpatient clinic setting. Adalimumab also allows a reduction in the use of steroids, with avoidance of some unwelcome side effects that steroids have. The fully human nature of adalimumab may reduce the risk of patients mounting an immune response against the drug.^[1]

Risks and Precautions

The most common adverse reaction with adalimumab is injection site reactions, including pain, redness, or itching where the drug is injected. Because adalimumab alters the function of the immune system, infections are an expected risk for people taking the drug. Tuberculosis, invasive fungal infections, and other opportunistic infections have been observed in people treated with adalimumab.

The risk of some types of cancer is increased in people taking adalimumab, presumably because an intact immune system provides some protection against cancer which is diminished by the drug.^[2]

References

1. ↑ Devlin SM, Panaccione R. Adalimumab for the treatment of Crohn's disease. Expert Opin Biol Ther. 2008 Jul;8(7):1011-9.Abstract
2. ↑ Scheinfeld N. A comprehensive review and evaluation of the side effects of the tumor necrosis factor alpha blockers etanercept, infliximab and adalimumab. J Dermatolog Treat. 2004 Sep;15(5):280-94. Abstract