Types Of Monoclonal Antibodies & Which Are FDA-Approved

Monoclonal antibodies have been in the news as a Covid-19 treatment and preventative measure. But monoclonal antibody therapy has been used for decades for conditions other than Covid-19. What types of monoclonal antibodies are there? Are they safe according to the FDA? Keep reading to learn more!

What are monoclonal antibodies?

Antibodies are proteins naturally produced by the immune system to protect the body from antigens – harmful substances that can damage the body like viruses, bacteria, parasites, or fungi. Monoclonal antibodies are lab-created to target specific antigens. They are created by harvesting antibodies from people who have recovered from a particular illness and then replicating them in a laboratory.

What are the different types of monoclonal antibodies and what do they treat?

There are numerous types of monoclonal antibodies that are FDA approved to treat a variety of conditions. Some examples include:

• Humira (adalimumab) is used to treat moderate-to-severe rheumatoid arthritis, psoriatic arthritis, and Crohn’s disease. It reduces the signs and symptoms of these conditions, inhibits disease progression, and can improve physical function. Other monoclonal antibody therapies that treat rheumatoid arthritis include rituximab and Cimzia.
• Xolair (omalizumab) is used to treat asthma, reducing attacks through the prevention of reactions caused by antigens like pollens or bacteria.
• Amevive (alefacept) treats psoriasis by preventing antigens from triggering immune responses that result in skin plaques. Another monoclonal antibody therapy that targets psoriasis is Raptiva.
• Synagis (palivizumab) is used to prevent Respiratory Syncytial Virus (RSV) in infants. It is not used to treat infection.
• Hercepin (trastuzumab) is part of a chemotherapy regimen to treat breast cancer. It is believed to block cancer cell receptors, blocking cancer growth. Other monoclonal antibodies that treat cancers include rituximab and Campath.

What types of monoclonal antibodies are FDA-Approved for Covid-19?

Currently, no monoclonal therapy for Covid-19 has U.S. Food and Drug Administration (FDA) approval. Because of the demands of the pandemic, the FDA instead has been issuing Emergency Use Authorization (EUA) for Covid-19 treatments.

The Pfizer vaccine was recently upgraded from EUA to having full FDA approval, and other Covid-19 vaccines and therapies are expected to receive the same as FDA administrative requirements are fulfilled.

There are two Covid-19 monoclonal antibody treatments which currently have FDA EUA:

• Sotrovimab by GlaxoSmithKline and Vir: This drug was shown to reduce hospitalization or fatality from Covid-19 by 85% compared to patients who did not receive monoclonal antibody treatment.
• Actemra (tocilizumab) by Genentech: This monoclonal antibody therapy was already an established treatment for autoimmune diseases like rheumatoid arthritis. Because it is already widely available, it quickly emerged as a Covid-19 therapy. It works by reducing inflammatory response, which is linked to severe disease progression in those infected with Covid-19.

Previously, the two treatments below were available for use under the FDA’s EUA, but that authorization was lifted in February of 2022.

• REGEN-COV2 by Regeneron: This monoclonal antibody treatment is a combination drug containing casirivimab and imdevimab. When compared to a placebo group in a recent study, there was an 80% reduction in hospitalization in infected patients who were treated with Regeneron.
• Bamlanivimab and bamlanivimab & etesevimab by Eli Lilly and Company: These therapies emerged early in the pandemic and proved effective against the originating strains. However, they lost efficacy as Covid-19 strains evolved, proving less effective against variants like Delta. EUA was temporarily paused for this drug, but it recently was reinstated specifically for the treatment of strains against which it is most effective.

What are FDA recommendations regarding monoclonal antibodies for Covid-19?

Monoclonal antibodies are available by prescription only to those who are at high risk of severe disease progression from Covid-19. The FDA guidelines defining who is at risk include people in the following groups:

• Pregnant people
• Obese people, including adults with a Body Mass Index (BMI) of 30 or higher, or children ages 12-17 with a BMI equal or greater to the 85th percentile
• People age 65 years or older
• People with certain medical conditions, including but not limited to immune disorders, chronic kidney diseases, diabetes, chronic respiratory diseases, cardiovascular diseases, hypertension, neurodevelopmental disorders, or medical-related technological dependence

Monoclonal antibodies can be prescribed regardless of vaccination status, though it should be noted that vaccination significantly reduces the likelihood that monoclonal antibody treatment will be necessary in the first place. Monoclonal antibodies must be administered within 10 days of when symptoms develop, before the body’s inflammatory response to the virus is triggered. People who have been hospitalized or prescribed oxygen are not eligible for monoclonal antibody therapy as it is too late for the treatment to make an impact.

Covid-19 monoclonal antibodies have FDA EUA to be prescribed for two purposes:

• To try and prevent infection after exposure
• To prevent severe symptoms from developing after testing positive

Studies are ongoing to explore monoclonal antibody therapy as a means of preventing the spread of Covid-19 between members of the same household. In those who have tested positive, monoclonal antibody treatments reduced hospitalization risk by 60-70%.

Experts agree that no types of monoclonal antibodies are sufficient alternatives to vaccination. The immunity benefits of monoclonal antibody therapy only last a month, versus the sustained protection of over six or more months provided by vaccination. The high cost of monoclonal antibody treatments, combined with the limited timeframe in which they can be given, makes vaccination the more practical and responsible choice.

Related:

• What Is The Easiest Way To Get A Covid-19 Test Before Traveling?
• The Differences Between Rapid PCR Vs RT-PCR Covid Testing
• How To Get A Same Day Rapid PCR Test In LA
• What Is The Cepheid 4-Plex And How Does It Work?
• How Does A Rapid PCR Test Work?