An antibody created by scientists is effective against a variety of COVID-19 variants, as well as related coronaviruses that could emerge now or in the future.
A monoclonal antibody shows promising results in neutralizing different variants of SARS-CoV-2 and other related animal viruses that might pose risks to humans. This antibody, known as SC27, has recently been detailed in Cell Reports Medicine.
This discovery allows for the potential development of broader and more effective treatments to combat current and upcoming COVID variants.
The monoclonal antibody SC27 was identified, created, and provisionally patented by a research team led by Greg Ippolito, Ph.D., who recently joined Texas Biomedical Research Institute (Texas Biomed) from the University of Texas at Austin. Other leaders in the team included Jason Lavinder, Ph.D., at UT and Ralph Baric, Ph.D., at the University of North Carolina at Chapel Hill.
“Other antibodies for COVID-19 have lost their effectiveness as SARS-CoV-2 has mutated over the years,” Dr. Ippolito, an Associate Professor, states. “Our new study indicates that the virus is less likely to evade this treatment because SC27 binds to several regions of the virus’s spike protein, including parts that mutate less frequently.”
SC27 functions in two significant ways: it blocks the ACE2 binding site, which the virus uses to connect with, enter, and infect human cells. Additionally, it attaches to a concealed or “cryptic” site on the bottom of the spike protein that tends to remain unchanged across variants, allowing SC27 to recognize a wide range of variants and related viruses. This recognition is critical, as an antibody must closely match the virus’s shape to neutralize it effectively; otherwise, the virus can escape the immune system.
The researchers assessed SC27 against 12 different viruses, including the original SARS-CoV-2, ongoing variants, and related coronaviruses found in bats and pangolins. The antibody proved effective in lab tests and protected mice from both tested variants.
“This makes it more comprehensive and effective than any other monoclonal antibody reported in scientific literature to date and surpasses previous FDA-approved antibodies,” Dr. Ippolito noted, although he emphasized that SC27 still requires testing in human clinical trials.
The research team aims to partner with industry to advance the SC27 monoclonal antibody treatment, which could be especially beneficial for immunocompromised patients who cannot receive vaccines. It may also serve as an emergency treatment during future outbreaks of new variants or coronaviruses. The next steps will involve preclinical studies with larger animal models, including nonhuman primates, which are crucial for evaluating how fully functioning immune systems respond to the treatment before moving to human testing.
Interestingly, SC27 was detected in individuals after receiving mRNA COVID-19 vaccines. Previously, this type of “class 1/4” antibody—known for binding to two distinct parts or “epitopes” of the spike protein—had only been found after natural infection from SARS-1.
“This is excellent news, as it shows that vaccines can encourage the production of these stronger and more effective antibodies,” Dr. Ippolito explains. “It indicates that future vaccine designs can aim to generate these antibodies and provide a sure way to gauge which vaccines will be the most effective.”
