Monoclonal antibodies (mAbs) are manufactured proteins that behave similarly to antibodies found naturally in the body. Researchers initially developed them for treating certain cancers but have now expanded their use to include conditions such as COVID-19.

The immune system naturally produces antibodies, which are proteins that can bind to certain types of foreign bodies, such as viruses and bacteria. However, some foreign substances can escape the detection of antibodies or overwhelm their response. Since cancer originates within the body’s own tissue, the immune system may have difficulty identifying cancer cells as being foreign.

Monoclonal antibodies supplement the body’s natural immune response, increasing its effectiveness at fighting certain infections and diseases.

Monoclonal antibodies gained widespread attention as researchers sought ways to treat COVID-19.

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Monoclonal antibodies are a type of synthetic, manufactured, antibody.

The immune system makes a wide range of antibodies. These are proteins that bind to specific antigens on target cells, such as bacteria.

Monoclonal antibodies work similarly, binding only to specific antigens. This can help the body fight disease. In some cases, the process can also identify disease by seeking out only the cells monoclonal antibodies bind to. Monoclonal antibodies can also carry treatments, such as cancer drugs, only to specific cells.

Monoclonal antibodies have several potential uses. They bind only to specific antigens, which makes them useful as a targeted intervention that leaves healthy cells alone.

Treating disease

Monoclonal antibodies can treat certain diseases by binding only to target cells. For example, a doctor may recommend monoclonal antibody therapy for certain types of cancer, such as breast cancer with specific hormonal markers.

This targeted therapy reduces the need to rely on broader therapies like chemotherapy that also kill healthy cells.

Monoclonal antibodies can work alone to supplement the activity of the immune system. A doctor may also use them to carry certain medications, such as anti-cancer drugs, only to specific cells.

Identifying disease

Monoclonal antibodies bind only to specific antigens. This can be useful in diagnosing certain diseases or assessing whether certain diseases are still present after treatment.

For example, researchers have used monoclonal antibodies to detect the presence of latent cytomegalovirus. They can also detect the presence of certain types of tumors or identify the location of cancer.

Because they are a relatively new innovation, researchers are still developing new ways to use them.

Researchers have identified numerous potential uses for monoclonal antibodies, and ongoing studies continue to identify more potential options.

Some current uses include:

  • Treating cancer, such as the drug blinatumomab. This drug binds to CD19 on leukemia cells, and CD3 on T cells, which helps T cells more effectively fight certain types of leukemia.
  • Treating certain hormonal breast cancers. For example, some monoclonal antibodies can target hormone receptors in certain types of breast cancers.
  • Treating COVID-19, especially in individuals at an increased risk of developing it. A number of monoclonal antibodies can help treat COVID-19, though some strains are less receptive to the drugs.

Numerous monoclonal antibody therapies may treat or slow the spread of cancer.

The three types include:

  • Naked monoclonal antibodies: These antibodies do not contain any drugs or radioactive material. They can either boost the body’s natural immune response or target certain diseased cells. One example is alemtuzumab, which can treat some types of chronic lymphocytic leukemia by binding to an antigen on lymphocytes.
  • Conjugated monoclonal antibodies: These mAbs deliver chemotherapy or radioactive substances directly to cancer cells. This targets diseased cells while reducing damage to healthy cells. For example, ibritumomab tiuxetan targets an antigen on B cells and can treat certain forms of non-Hodgkin’s lymphoma.
  • Bispecific monoclonal antibodies: These drugs can attach to two different antigens. For example, blinatumomab attaches to an antigen on leukemia cells, as well as one on T cells, making it easier for T cells to find and fight acute lymphocytic leukemia.

Different monoclonal antibodies have slightly different side effects, and the side effects also vary from person to person. In general, people may experience:

  • skin reactions at the injection site, such as:
    • swelling
    • itching
    • redness or discoloration
    • a bump
    • pain
  • flu-like symptoms such as:
    • fever
    • chills
    • low energy
    • feeling unwell
  • heart disease and heart failure
  • high blood pressure
  • skin and mouth sores that may become infected
  • heart attacks
  • allergic reactions, including serious and life threatening ones

Some side effects are not as common. Individuals can speak with their healthcare professional about any side effects and concerns they may have.

Some questions to ask a doctor or specialist before using monoclonal antibodies include:

  • What does the data show about the effectiveness of this treatment?
  • Are there other treatments I should try first?
  • Are other treatments more likely to be effective?
  • Can monoclonal antibodies cure this disease?
  • If this disease is incurable, by how long might monoclonal antibodies prolong survival?
  • What are the risks of treatment, and what should I do if I experience side effects?

What are the disadvantages of monoclonal antibodies?

Monoclonal antibodies can be expensive and inaccessible without insurance. Like other medications, they may also cause side effects, including serious diseases such as heart failure. Monoclonal antibodies are not always effective.

What are the three types of monoclonal antibodies?

Monoclonal antibodies may be naked, which means they contain no drugs or radioactive ingredients and work by amplifying the immune system. They may be conjugated, which means they deliver drugs to affected cells. Or they may be bispecific, which means they bind to two different types of antigens.

How effective are monoclonal antibodies for COVID?

The effectiveness of monoclonal antibodies for COVID depends on the strain of COVID a person has, but these antibodies tend not to be effective for more recent versions. They may reduce the length and severity of illness but do not cure the infection.

Monoclonal antibodies are an emerging treatment for many diseases but show significant promise for treating cancer. This is because these antibodies can target specific cells without leading to the harmful systemic effects that many traditional drugs cause.

Researchers continue to explore options for using these medications as well as factors that increase their effectiveness and safety.