Update on Monoclonal Antibodies
One of the most effective weapons we have had in the battle against the SARS-CoV-2 coronavirus has been monoclonal antibodies. Unfortunately, late last month the U.S. Food and Drug Administration (FDA) pulled its approval for two of the monoclonal antibody therapies that have been in use since early last year because they don’t work against the omicron variant of the virus.
Since then, our primary care doctors at Cohen Medical Associates in Delray Beach have received a number of calls asking for more information.
So here’s what we know at this time.
What are monoclonal antibodies?
Monoclonal antibodies are a laboratory-created type of treatment first developed in the 1970s to prevent the rejection of transplanted organs and tissue.
The synthetic proteins in monoclonal antibodies work by mimicking the body’s natural immune system. They can, therefore, offer immediate protection against COVID-19 instead of waiting for the body to mount its own response. This gives the body time to make its own antibodies to fight off the virus.
In most cases, they also prevent further infection of more cells, effectively halting the disease process. Given to those with mild to moderate COVID-19 symptoms, or who are at high risk of admittance to the hospital or dying from COVID-19, studies have shown they can be 75-80 percent effective in preventing worsening of symptoms.
Why pull the two monoclonal antibodies?
Early in January, the National Institutes of Health (NIH) updated its guidelines to advise against the use of two types of monoclonal antibodies because studies had shown they were not effective against the omicron variant, which now accounts for more than 99 percent of COVID-19 cases nationwide, according to the Centers for Disease Control and Prevention (CDC).
Their findings were based on several scientific studies, including trials by the manufacturers of the drugs, showing that the drugs didn’t work against the predominant omicron variant.
“That’s why the FDA withdrew it,” infectious disease specialist Dr. Larry Bush of Wellington told WPTV. “I think they look at it like, if they allow [ineffective monoclonal antibody treatments] to go on, it potentially harms you because it keeps you from going to get something that could help you.”
Despite some people’s contention that they are in fact effective against omicron, research indicates they are not.
Risks of the treatment
And these drugs are not risk-free.
The NIH reports the therapy may cause several side effects, including:
- mild pain
- bleeding, bruising, or soreness of the skin
More severe reactions can include:
- thrombotic-type episodes (blood clots)
- arterial hypertension
- changes in heart activity
- slowed bone marrow activity
- impaired renal function
Other treatments still available
Although these two particular monoclonal antibody treatments were pulled, there is still a third type available at some area hospitals: sotrovimab, produced by GlaxoSmithKline.
And according to the Florida Health Department, AstraZeneca’s Evusheld monoclonal antibody therapy has authorization for pre-exposure prevention of COVID-19 in those who are moderate to severely immunocompromised or for individuals who have a history of severe reactions to COVID-19 vaccines.
The oral antiviral pills Paxlovid and Molnupiravir are available by prescription only for those who are considered to be at high risk for severe illness (i.e., possible hospitalization or death) from COVID-19, so you will need to let us know if you have had a positive test result for COVID-19 and want to try these drugs.
In addition, to be eligible for Paxlovid you must be age 12 or older. To be eligible for Molnupiravir, you must be age 18 or older.
Finally, last month the FDA approved the intravenous treatment remdesivir. It has approval for use in outpatients who are at high risk of admittance to the hospital. Its limited use previously applied to those in hospital settings, because administration calls for trained clinicians in three doses over three days. Still, it has proven effective treatment, reducing the risk of hospitalization and death by 87 percent when given soon after diagnosis, according to a December study.
Prevention is best
Even with all these treatments (some of which are currently in short supply), the best protection remains the vaccines.
“Unfortunately, the demand [for treatments] has clearly outstripped the supply,” Bush told WPTV. “The recommendation is still for people to make sure you’re vaccinated and have a booster. And if you do get diagnosed with COVID [after being vaccinated], most likely you’re going to be fine and have mild disease.”
“But if you have a mild to moderate underlying risk factor, you should try to get sotrovimab,” he added.
Risk factors include obesity, diabetes, kidney disease, heart or lung disease, or being over the age of 60.
If you have questions or have tested positive for COVID-19 and are at high risk of hospitalization or dying from the illness, be sure to contact us to help you determine the best course of treatment for you.