Novavax Inc, Rockville, Md, and the University of Massachusetts Medical School have concluded a preclinical study of a respiratory syncytial virus (RSV) vaccine candidate. The vaccine candidate incorporates certain virus-like-particles (VLPs) and is Novavax’s first recombinant VLP for the prevention of RSV. The VLP contains the core protein of Newcastle disease virus decorated with a human RSV attachment glycoprotein, which is important for inducing immunity against the RSV.
The candidate VLP vaccine induced strong antibody responses against RSV, protected mice against RSV replication in the lungs, and did not lead to enhanced inflammation of the airways. The data supports continued development of this and additional RSV VLP vaccine candidates containing other proteins important for immunity.
"I am pleased we have been able to demonstrate that virus-like particles, based on Newcastle disease virus proteins, can be used as a platform for the development of human vaccines," says Trudy G. Morrison, PhD, professor of molecular genetics and microbiology, who presented the results of the study, supported by Novavax, at the 2nd Vaccine Congress in Boston on December 9, 2008.
To conduct the study, mice were immunized with one of four doses of the RSV VLP vaccine candidate, inactivated RSV, live RSV, or a placebo. The antibody responses to the RSV VLPs were higher than the antibody responses to inactivated or live RSV. Antibody titers also increased with higher VLP doses.