Lab-created monoclonal antibodies, once a leading way of protecting people against COVID-19, are being sidelined because they don’t work against a growing number of coronavirus variants.
“Monoclonals had their day, like the Model T or the biplane,” Carl Dieffenbach, director of the Division of AIDS at the National Institutes of Health and lead of the NIH’s Antiviral Program for Pandemics, told NPR. “Now it’s time to move on.”
More than 3.5 million infusions of monoclonal antibodies have been given in the United States since first being authorized in 2020 before COVID vaccines were available, NPR reported.
Monoclonal antibodies are created in a laboratory and work like the natural antibodies your body makes to fight illness. For COVID-19, they’re designed to bind to spike protein on the virus’s surface, stopping the virus from invading human cells.
But the monoclonal antibodies designed for one strain of COVID may not bind to the spike proteins of other strains. Many companies stopped making monoclonal antibodies because they don’t want to spend millions creating a product that will be quickly scrapped, NPR said.
This is a problem for millions of people with weakened immune systems who may not respond well to COVID vaccines, The Washington Post reported. Those people need antibody therapies for protection.
Last January the FDA revised its emergency use authorization for two monoclonal antibody combinations to treat mild-to-moderate COVID-19, because they are not effective against the dominant Omicron variant. The drugs were for bamlanivimab combined with etesevimab from Eli Lilly and casirivimab with imdevimab from Regeneron.
Drug companies and scientists are trying to develop new monoclonal variants that won’t become outdated as COVID mutates.
The Canadian biotech company Immune Biosolutions is conducting clinical trials on a mist that can be sprayed into a person’s mouth, The Washington Post reported. The Post said an antibody in the drug targets the stem helix of the coronavirus, which has not changed much on variants and subvariants.
Scientists at the Antibody Biology at NIH also taking a similar approach, NPR reported. “We’re looking at other parts of the spike protein that may be more consistent and may be harder to mutate,” said Joshua Tan, chief of the unit.
NPR: “How monoclonal antibodies lost the fight with new COVID variants”
FDA: “Coronavirus (COVID-19) Update: FDA Limits Use of Certain Monoclonal Antibodies to Treat COVID-19 Due to the Omicron Variant unit.”
The Washington Post: “Coronavirus variants are dodging antibody treatments. New lab-made options may help”