While many are hopeful that monoclonal antibodies will prove to be a powerful treatment, they also show some potential as a preventative measure.
Dr. Stuart Cohen is chief of the Division of Infectious Diseases and director of Hospital Epidemiology and Infection Prevention at UC Davis Health.
“As opposed to a vaccine trial, which we call active immunity where we’re expecting the body to make its own immune system, this is what we call passive immunity where the immune system – or immune substances in this case – are given to people,” explained Dr. Cohen.
Many of the possible antibody treatments being studied are made of more than one antibody – also known as a cocktail.
“What has been seen with some viruses is that if you have a single target, the virus can develop resistance and avoid that single target. So by using two, you sort of decrease the chance of the virus developing resistance and basically being able to go through these monoclonal antibodies,” he said.
Giving someone antibodies directly means the protection kicks in sooner than if they received a vaccine, because it can take several days for the body’s immune system to respond to a vaccine and begin producing its own antibodies.
While monoclonal antibodies and vaccines for COVID-19 have yet to be proven effective and safe, theoretically, immunity does not last as long with monoclonal antibodies as it would with a vaccine.
“What typically happens is it takes a couple of months to clear these antibodies out of the human body, and then you’re not protected. It’s like you’ve never received anything,” said Dr. Cohen.
Monoclonal antibodies are also very complicated and expensive to manufacture, which means they cannot be produced at the same scale as vaccine candidates.
So while they present a lot of potential in fighting the virus, Dr. Cohen says ultimately, “the vaccine is the best way to put this pandemic into a box and move forward.”