Monoclonal antibodies are a type of biologic medication that may be used to treat rheumatoid arthritis if other treatments aren’t effective. There are several different ways monoclonal antibodies target rheumatoid arthritis disease activity.

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Rheumatoid arthritis (RA) is an autoimmune disease in which your immune system attacks your joint tissue. This leads to symptoms like joint pain, stiffness, and swelling.

The treatment of RA often involves medications that help to lessen your body’s immune response, preventing further joint damage. Some RA drugs are monoclonal antibodies.

Antibodies are proteins made by your immune system, typically in response to exposure to viruses or bacteria. They bind to a specific target, called an antigen, and help to protect you from future exposures.

A monoclonal antibody (mAb) works by the same principle. mAbs are produced in a lab and target a specific factor in your body, such as a protein on the surface of a cell.

Because of their specificity, mAbs can provide a more targeted treatment approach than other drugs that have a more general effect. They treat a wide variety of conditions, including autoimmune diseases, cancer, and migraine.

The Food and Drug Administration (FDA) has approved several mAbs for the treatment of RA. These mAbs target a variety of factors involved in RA disease.

mAbs fall under the category of RA treatment called disease-modifying antirheumatic drugs (DMARDs). They’re classified as biologic DMARDs, or more simply as “biologics,” because they come from a living source.

TNF-alpha inhibitors

TNF-alpha is a signaling protein called a cytokine that’s made by your immune system. When it binds to its receptors, it increases inflammation. mAbs that bind to TNF-alpha can block its activity, lowering inflammation levels.

The TNF-alpha inhibiting mAbs approved for the treatment of RA include:

IL-6 receptor inhibitors

IL-6 is another cytokine that’s associated with inflammation. IL-6 receptor inhibitors bind to the receptor for IL-6, preventing IL-6 from binding to it. This helps to reduce inflammation.

The available mAbs that inhibit the IL-6 receptor in RA are sarilumab (Kevzara) and tocilizumab (Actemra).

B-cell inhibitors

B cells, a type of immune cell that makes antibodies, may also contribute to RA disease. mAbs that inhibit B cells bind to a protein on their surface called CD20. Rituximab (Rituxan) is a mAb that inhibits B cells and can be used to treat RA.

Other antibody-derived drugs for RA

There are also drugs for RA that aren’t made up of an entire mAb but are instead composed of parts or fragments of antibodies. These include:

  • abatacept (Orencia), a drug that blocks the activation of T cells, an immune cell that’s also involved in inflammation
  • certolizumab (Cimzia), a TNF-alpha inhibitor
  • etanercept (Enbrel), a TNF-alpha inhibitor

Before prescribing mAbs for your RA, a doctor will consider your medical history to make sure it’s safe for you to take a mAb. They may also order tests to look at your levels of blood cells and liver enzymes.

mAbs affect the activity of your immune system. This means you’re at a higher risk of infection while you’re taking them.

Because of this, a doctor will make sure that you don’t currently have an active infection. They’ll also check for chronic infections like tuberculosis, hepatitis B, or hepatitis C.

Additionally, live vaccines, such as the measles, mumps, and rubella (MMR) vaccine and the chickenpox vaccine, aren’t recommended for people taking mAbs. Before starting a mAb, a doctor may ask you to update your vaccines, including vaccines for:

How you receive your mAb treatment will depend on which one is prescribed to you. The frequency at which you receive treatment can also vary based on the mAb you’re taking.

In some situations, you’ll be able to give yourself your mAb by injecting it under your skin. You’ll be instructed on how and where to inject your mAb and will need to rotate injection sites so one particular area doesn’t become irritated.

The mAbs that you can inject yourself include:

  • adalimumab (Humira)
  • sarilumab (Kevzara)
  • tocilizumab (Actemra)

Other mAbs can be given at a doctor’s office, either by using an intravenous (IV) infusion or by injecting the medication under the skin, depending on the specific medication. These include:

  • golimumab (Simponi)
  • infliximab (Remicade)
  • rituximab (Rituxan)
  • tocilizumab (Actemra)

Infusions for the above mAbs usually take around 2 to 4 hours.

After taking your mAb, it’s important to notify a doctor if you have significant side effects or develop symptoms of an infection. If you develop an infection, your mAb treatment is typically stopped until your infection clears.

Like any type of drug, mAbs can have a variety of side effects. These can vary based on the specific type of mAb that you’re taking for your RA. Some examples of common side effects associated with the mAbs used for RA are:

Serious side effects of mAbs are rare but can occur. For example, because they suppress immune activity, all mAbs are associated with an increased risk of serious infections.

Additionally, TNF-alpha inhibitors can cause:

Biologics like mAbs are typically only recommended when traditional DMARDs haven’t been effective at managing RA. Methotrexate is the traditional DMARD that’s preferred for treating RA.

In some cases, you may have a combination treatment with a mAb and methotrexate. A 2021 review notes that some mAbs, such as TNF-alpha inhibitors, are more effective when combined with methotrexate.

When you first start on mAbs, it’s important to be patient. This is because it can take months to receive the full effect of these drugs.

RA is also a complex condition. As such, a specific mAb may work well for one person and not for another.

A 2021 study notes that while 50% to 70% of people with RA respond to biologic DMARDs like mAbs, a significant amount don’t respond or have an adverse reaction to them.

If your mAb treatment isn’t effectively managing your RA, a doctor may switch you to another mAb or a different type of RA drug.

mAb treatment for RA can be costly. For example, a 2018 report found that the average yearly prescription cost for infliximab (Remicade) was $17,335.

Another 2018 report found that yearly RA-specific medical costs were significantly higher for individuals taking biologics like mAbs than for individuals using other treatment types.

A 2020 study looked at several biologics for RA, including adalimumab (Humira), golimumab (Simponi), and tocilizumab (Actemra). From 2010 to 2019, list prices increased for every product.

The researchers also found that the average estimated yearly out-of-pocket cost for biologics for RA was lower in 2019 ($4,801) than it was in 2010 ($6,108). However, much of the cost savings are being lost to drug price increases.

Biosimilars are another option. They are almost identical to the original biologic and are manufactured when the drug patent expires. Biosimilars are less expensive alternatives to biologics.

What are the other drug types used to treat rheumatoid arthritis?

Other drugs that may be used to treat RA include:

What are lifestyle modifications for rheumatoid arthritis?

Lifestyle modifications that can help with RA and can be used along with medications are:

How many people have rheumatoid arthritis?

It’s estimated that 1.3 million adults in the United States have RA. This is about 0.6% to 1% of the adult population.

Monoclonal antibodies are sometimes used to treat RA. They fall under a class of RA drugs called biologics and are only typically prescribed if traditional DMARDs haven’t been effective at managing your RA.

There are several different types of mAb used for RA. These vary off of the aspect of the immune system that they target. The aim of all mAbs is to lower the levels of inflammation in the body, thereby slowing or stopping joint damage.

All mAbs for RA come with a variety of side effects. If a doctor recommends a mAb for your RA, be sure to discuss the various benefits and risks of that specific mAb with the doctor before starting on it.