Updated COVID vaccines have been available in the United States since September. These updated vaccines are designed to target the XBB coronavirus variant, which had been causing the majority of COVID cases in 2023.
But what if a different variant starts to take over this winter? A new study published in Nature offers reassuring data.
“Our research shows that the updated vaccines likely produce a strong antibody response to several variants including XBB.1.5, EG.5.1, and BA.2.86,” says Lihong Liu, PhD, assistant professor of medical sciences at Columbia University’s Vagelos College of Physicians and Surgeons, who co-led the research with David D. Ho, MD, the Clyde’56 and Helen Wu Professor of Medicine, professor of microbiology & immunology, and director of the Aaron Diamond AIDS Research Center.
Related—Reviving an Ineffective Class of COVID DrugsMonoclonal antibody therapy is crucial for protecting immunocompromised people from COVID, but virus evolution has incapacitated all previously effective monoclonal antibodies. Liu and Ho identified two new monoclonal antibodies that neutralize all current variants, making them prime candidates for development into new COVID drugs for people with weak immune systems.
The researchers found that XBB breakthrough-induced antibodies successfully neutralized the spike protein of not only the XBB.1.5 variant, but also the EG.5.1, and BA.2.86 variants. Since the updated vaccines are based on XBB, they likely protect against the EG.5.1 and BA.2.86 variants as well.
“While these results are encouraging, it’s essential to remain vigilant, as the virus continues to circulate and evolve,” Liu says. “It could quickly develop further mutations that make the current vaccines and therapies less effective at any point, so it’s important that we keep monitoring it and doing these studies on antibody effectiveness.”
By genetically modifying BA.2.86, the researchers identified six mutations that increased the resistance of the spike protein to antibodies. This important information will help virologists track which newly evolved variants could pose a greater danger in the future.
Evolutionary tree of COVID-19 variants.