Monoclonal Antibody Therapy

Monoclonal antibodies are used in many drugs, like Humira, as a source of antibody therapy. Monoclonal antibodies are synthetic antibodies, created from cloned B cells¹. They only recognize a single epitope and are expensive to make, so they are only made if these antibodies can result in a substantial profit due to a widespread need and usage of the antibody.

A medication containing a monoclonal antibody that is commonly advertised on television is Humira, or adalimumab. This drug can be used in the treatment of a variety of illnesses: rheumatoid arthritis, psoriatic arthritis, plaque psoriasis, ankylosing spondylitis and Crohn’s disease. It slows or prevents the destruction of joints for patients with arthritis, and it prevents the narrowing of the stomach or intestinal perforation in patients with Crohn’s disease, leading to remission². This drug works by binding to TNF and blocks its ability to produce IFN alpha, reducing inflammation³.

Although it has many benefits to the health of patients battling these specific diseases, adalimumab has considerable side effects as well. Side effects include⁴: 

• Headache
• Rash 
• Nausea 
• Upset stomach 
• Swelling, redness or pain at site of injection 
• Upper respiratory infections 
• Heart failure (shortness of breath, swelling of ankles and feet, sudden weight gain) 
• Immune reactions including a lupus-like syndrome (chest discomfort or pain that does not go away, shortness of breath, joint pain, or rash on your cheeks or arms that gets worse in the sun)
• Liver problems (fatigue, yellow skin or eyes, poor appetite or vomiting, pain on right side of stomach) 
• Psoriasis 
• Hypersensitivity reactions (including anaphylaxis) 
• Reduced levels in blood of platelets and red cells (aplastic anemia)

In addition, it has been associated with many other diseases. It may increase the risk of reactivating the Hepatitis B virus in patients that are chronic carriers. In addition, it may suppress the immune system, so it is associated with minor infections of urinary tract, respiratory tract, and sinuses. Also, it may worsen the symptoms of nervous system diseases. In some studies, cancer developed in patients that took adalimumab. Lastly, it is associated with sepsis, tuberculosis, and fungal infections. If a patient has an active infection, they should not take adalimumab, because it is a TNF blocker medicine that can lower the immune system’s ability to fight off infection⁵.

Because it binds to and blocks the actions of TNF, adalimumab does impact the immune response. TNF is a cytokine of both the innate and acquired immune system, as its sources are macrophages, T cells and NK cells. Its job is to promote inflammation and regulate certain immune functions, and it is cytotoxic for some tumor cells⁶. Adalimumab negatively impacts the innate and acquired immune response because it blocks the actions of TNF, and that is why it is important that patients with an active infection do not take this drug so they can effectively fight off their infection.

Although I had seen this medication widely advertised before writing this blog, I never knew that it used a monoclonal antibody or how it specifically treated patients. It is also interesting to see how many monoclonal antibody therapies are available, considering that they were first made in 1975. Hopefully research in monoclonal antibody therapy can continue so more patients of different diseases can be helped.

References:

1. Anderson, Denise, Sarah N. Salm, Deborah P. Allen, and Eugene W. Nester. Nesters Microbiology: a Human Perspective. New York: McGraw-Hill Education, 2019. p. 465
2. Omudhome Ogbru, PharmD. “Adalimumab (Humira): Arthritis Drug Uses, Dosage & Side Effects.” MedicineNet. MedicineNet, July 1, 2019. https://www.medicinenet.com/adalimumab/article.htm.
3. “Learn How HUMIRA Works for Moderate to Severe Crohn’s Disease.” HUMIRA® Crohn’s Disease Medication | How It Works. Accessed April 19, 2020. https://www.humira.com/crohns/how-humira-works-for-crohns.
4. “HUMIRA® (Adalimumab): A Biologic Treatment Option.” HUMIRA® (adalimumab) | A Biologic Treatment Option. Accessed April 19, 2020. https://www.humira.com/.
5. “HUMIRA® (Adalimumab): A Biologic Treatment Option.” HUMIRA® (adalimumab) | A Biologic Treatment Option. Accessed April 19, 2020. https://www.humira.com/.
6. Anderson, Denise, Sarah N. Salm, Deborah P. Allen, and Eugene W. Nester. Nesters Microbiology: a Human Perspective. New York: McGraw-Hill Education, 2019. p. 370.