Protein-designed RSV vaccine in clinical trials

Nanoparticle technology created by researchers at the University of Washington School of Medicine is featured in a vaccine for respiratory syncytial virus (commonly known as RSV). The vaccine is now undergoing testing in human clinical trials.

RSV can infect anyone or any age. It can be serious in infants, the elderly and those with immune-compromising conditions or receiving treatments that lower their resistance. Pneumonia from RSV is a major cause of infant mortality in countries with scarce medical resources.  

The vaccine showed promise in Phase 1 trial results published earlier this year. A new trial is now testing a slightly altered version of the shot in the form of a bivalent vaccine designed to protect against both RSV and human metapneumovirus (HMPV). Older adults are enrolled to receive the bivalent vaccine in the current trial. Initial results are expected in mid-2023. All trials for the vaccine are run through Seattle-based biotechnology company Icosavax.

“(The vaccine) is marching forward in clinical development,” said Neil King, whose UW Medicine lab in the UW Medicine Institute for Protein Design pioneered the nanoparticle technology for the vaccine.

“We're hoping that it will be available in a very short time, maybe a couple of years.”

King is an assistant professor of biochemistry at the University of Washington School of Medicine. His lab’s nanoparticle technology formed the basis of a COVID-19 vaccine, which was approved for clinical use in South Korea this summer.

King says COVID-19 and RSV are just the initial targets for the protein-designed nanoparticle system.  The system is a symmetrical protein platform on which bits of virus that trigger an immune response are arrayed. Among other reasons, the symmetry of the platform, like the symmetrical shapes of viruses, is recognized by the immune system as one of the signs to build up its defenses. 

“I feel like we're just finally at the starting line,” said King. “I feel like the world is in front of us now and there are so many problems to solve. The technology that we have built and are continuing to build will hopefully allow us to solve problems even faster.”

There is currently no approved RSV vaccine in the United States. Two other companies are reporting promising Phase III trial results of their vaccine candidates. Pfizer says its version is safe and effective at protecting newborns when administered to pregnant mothers. That company announced plans to submit an application for Food and Drug Administration approval by the end of 2022. GSK’s candidate was found to be 94% effective at reducing severe disease in older adults.

Download broadcast-ready soundbites detailing the protein-designed RSV vaccine created in Neil King's lab.

UW Medicine