Monoclonal Antibodies: Purpose, Risks & Results

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This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

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Monoclonal antibodies (mAbs) are treatments that target specific proteins and help your immune system fight disease. They can also reduce inflammation caused by your immune system. Healthcare providers use monoclonal antibodies to treat autoimmune diseases, cancer, neurological diseases, osteoporosis, infectious diseases and more.

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Monoclonal antibodies (also called moAbs or mAbs) are treatments that help your immune system fight diseases or block proteins that cause diseases. They’re made up of many copies (clones) of a single antibody that recognize a specific target. Scientists make monoclonal antibodies in a lab.

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Antibodies are proteins made by your immune system. They seek out specific targets and stick to them. This prevents their function and/or allows your immune cells to destroy the cells the targets are attached to.

Monoclonal antibodies are most often used to treat cancer, autoimmune diseases and inflammatory conditions. But they’re also used to treat:

Asthma and allergies
Eye conditions
High cholesterol
Neurological conditions
Migraines
Osteoporosis
Some infections, including RSV and Ebola

Scientists also use monoclonal antibodies in medical research and testing.

Monoclonal antibody treatments work in different ways, depending on what they’re designed to treat. They can:

Mark cells so that your immune system knows to destroy them
Cause cancer cells to die
Block proteins that cancer cells need to grow
Block blood vessel growth to cancer cells
Block proteins that cause inflammation or disease
Slow down (suppress) your immune system so it doesn’t attack your body or a transplanted organ
Be used to deliver radiation or chemotherapy directly to a target

You’ll receive monoclonal antibodies through an IV in a vein. A healthcare provider will monitor you for any signs of reaction or side effects to the treatment. How often and how long you’ll need the treatment depends on what you’re being treated for.

In some cases, your healthcare provider might also prescribe a monoclonal antibody that’s injected under your skin (subcutaneous). A provider might give it to you at the hospital. Or they’ll teach you how to give yourself a shot, usually in your belly or upper thigh.

The main benefit of monoclonal antibody treatments is that they’re made to attach to a very specific target. This can mean fewer side effects than other treatments.

Some monoclonal antibodies are designed to suppress your immune system, which may make you less able to fight off germs. Many “rev up” your immune system, which can cause unwanted and sometimes serious side effects, or infusion reactions. These include:

Common signs of infusion reactions include:

Rash
Fever
Chills
Shortness of breath
Sweating
Blood pressure changes
Racing heart

Your provider may slow down the infusion or reduce the dose to avoid infusion reactions.

Talk to your healthcare provider about what kind of side effects or reactions to look out for. Call them or go to the emergency room if you’re having an unexpected reaction after monoclonal antibody treatment.

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No, monoclonal antibody treatments aren’t what people typically think of as chemotherapy. They’re often called biologics, targeted therapy or immunotherapy, depending on how they work.

Your immune system is a powerful tool. Monoclonal antibodies can use that tool to target harmful cells or substances in your body. Healthcare providers use monoclonal antibodies to treat many types of illnesses and conditions. Your provider can talk to you about what you can expect with your specific treatment.

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Cleveland Clinic’s health articles are based on evidence-backed information and review by medical professionals to ensure accuracy, reliability and up-to-date clinical standards.

Cáceres MC, Guerrero-Martín J, Pérez-Civantos D, Palomo-López P, Delgado-Mingorance JI, Durán-Gómez N. The importance of early identification of infusion-related reactions to monoclonal antibodies (https://pubmed.ncbi.nlm.nih.gov/31447561/). Ther Clin Risk Manag. 2019 Aug 1;15:965-977. Accessed 12/10/2025.
Chabner BA, Fathi AT, Raje NS, et al. Pharmacology and Toxicity of Antineoplastic Drugs. In: Kaushansky K, Prchal JT, Burns LJ, Lichtman MA, Levi M, Linch DC, eds. Williams Hematology. 10th ed. McGraw-Hill Education; 2021.
Gklinos P, Papadopoulou M, Stanulovic V, Mitsikostas DD, Papadopoulos D. Monoclonal Antibodies as Neurological Therapeutics (https://pmc.ncbi.nlm.nih.gov/articles/PMC7912592/). Pharmaceuticals (Basel). 2021 Jan 26;14(2):92. Accessed 12/10/2025.
National Cancer Institute (U.S.). Monoclonal Antibodies (https://www.cancer.gov/about-cancer/treatment/types/immunotherapy/monoclonal-antibodies). Posted 9/24/2025. Accessed 12/10/2025.
Pantaleo G, Correia B, Fenwick C, Joo VS, Perez L. Antibodies to combat viral infections: development strategies and progress (https://pubmed.ncbi.nlm.nih.gov/35725925/). Nat Rev Drug Discov. 2022 Sep;21(9):676-696. Accessed 12/10/2025.

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Peptide Therapy Guide Editorial Team