Not just a Trump-touted 'cure': Monoclonal antibodies may be 'bridge' to coronavirus vaccine
Antibody drugs like the one that President Donald Trump praised after treatment earlier this month aren't just for COVID-19. For the past 30 years, this type of medicine has been used to treat cancer, inflammatory diseases, and infections. Although experts say this type of medicine could make a change for COVID-19, it is not a "cure," as the president has sometimes touted, nor is it intended to replace a vaccine.
Antibodies are our natural response to infection. They can be obtained from the blood of recovered patients or - with the help of modern technology - produced synthetically in a laboratory.
The idea of using antibodies as a medical treatment dates back to the 1890s, when Emil von Behring successfully treated children suffering from a severe bacterial infection called diphtheria with antibody-containing serum from the blood of horses recently exposed to the same bacteria. The discovery earned him the first Nobel Prize in Medicine.
Almost a century later, scientists Georges J. F. Köhler and César Milstein learned to construct cells that produced many copies of a single antibody that could be used to treat disease in the 1970s. These drugs, known as monoclonal antibodies, use concentrated, high numbers of identical antibodies to target a very specific target.
MORE: Trump's COVID-19 treatment was developed using cells originally taken from fetal tissue
The first monoclonal antibody was approved for use in kidney transplant rejection in the 1980s. By 2019, the Food and Drug Administration had approved 79 monoclonal antibody drugs.
"Antibodies make up some of the most important drugs in the world for treating cancer to autoimmune diseases," said Dr. Eline Luning Prak, professor of pathology at the University of Pennsylvania.
The drugs, sometimes called "biologics," treat a variety of diseases - from cancer to eczema to certain types of arthritis. Humira, the branded version of a drug called adalimumab, was the world's best-selling drug in 2018, generating $ 19.9 billion in sales for drug maker AbbVie.
PHOTO: Regeneron Pharmaceuticals' company logo appears on a building on the company's Westchester campus in Tarrytown, New York on September 17, 2020. (Brendan McDermid / Reuters, File)
And last week, biotech company Regeneron - the same company that receives the Trump drug - received FDA approval for its first Ebola treatment, Inmazeb, a mixture of three monoclonal antibodies. These antibodies target parts of the external protein that Ebola uses to attach to and infect human cells.
When it comes to COVID-19, antibody drugs, all of which are still experimental and not yet proven to work, block the virus' ability to attach to and infect cells in the body. Companies like Regeneron, Eli Lilly, and AstraZeneca are currently in late-stage trials.
"These antibodies have been engineered to bind to very specific sites on the SARS-CoV-2 spike protein," explained Dr. Thomas Campbell, a physician at the University of Colorado Medical School who heads the Colorado office for Regeneron's COVID-19 trials to treat antibodies.
"It's a way to give you quick protection when you're already in trouble," said Prak. The drugs are designed to protect patients who are already infected when the body doesn't have enough time to develop its own immune response.
MORE: An Unusual Patient, An Unusual Treatment: Trump and the Risks of VIP Syndrome
Monoclonal antibodies are not the same as convalescent plasma - another high-profile experimental COVID-19 treatment. The treatments are similar, however, with both being shorthand for the body's natural defense against a foreign invader - a concept known as passive immunity.
Convalescent plasma, according to Prak, is "a mixture of hundreds or thousands of different antibodies" that target multiple sites on the virus. Monoclonal antibody treatments have a high concentration of a single specific antibody, making the drug more effective than convalescent plasma.
These treatments, used for a wide variety of diseases, are not without risk. Depending on where in the body the antibodies bind, the drugs can cause different effects. Pharmaceutical company Genentech, for example, withdrew efalizumab, which was originally approved for the treatment of psoriasis, from the US market because it was linked to the risk of fatal brain infections in 2009.
PHOTO: In this undated picture from a video made available by Regeneron Pharmaceuticals on Friday, October 2, 2020, vials are being examined at the company's facilities in New York state for an experimental coronavirus antibody drug effort. (Regeneron via AP)
Another company, Janssen, stopped making a synthetic antibody in 2010, partly due to serious side effects, some of which were potentially fatal.
Although synthetic antibodies are currently being tested to prevent COVID-19 in addition to treating the disease, researchers do not yet know if this type of drug can fight off the virus. And they say that even if it works, protection will likely only last a short time.
"If they last a few weeks to a month, they will likely run out of protection in six months or a year," Campbell said.
MORE: Trump falsely dismisses the virus threat: "You catch it, you get better and you are immune."
Alternatively, vaccines teach the body to recognize foreign invaders like the new coronavirus and give the body a longer lasting immunity.
However, experts say monoclonal antibodies could act as a "bridge" to a vaccine and work together to fight the pandemic.
"The people most at risk of COVID are the ones who may have rather poor vaccine responses," said Prak. "In this population, this type of therapy could be very useful."
Miranda Rosenberg, M.D., is a dermatologist at the University of Miami and a member of the ABC News Medical Unit.
Not just a "cure" touted by Trump: Monoclonal antibodies can act as a "bridge" to the coronavirus vaccine originally published on abcnews.go.com
Click to receive the most important news as a notification!
'The Bachelorette': Who Is Zach Jackson?
Blockbuster deal: Callaway announces merger with Topgolf
UK Vaccines Taskforce Chair says early COVID-19 vaccines may be imperfect: The Lancet
Oscar Pistorius: BBC removes documentary trailer after backlash
'I Don't Feel Safe': Pa. Mom Filed Protective Order Against Husband, Who's Now Accused of Murder
Will the Electoral College favor Biden or Trump? Here’s what researchers predict