Invivyd Selects VBY329 as Potential Best-in-Class RSV Antibody for Pediatric Prevention
核心洞察
Invivyd has identified VBY329 (搜索), a monoclonal antibody candidate that demonstrates 1.5-fold greater antiviral potency than nirsevimab and up to 500-fold enhanced neutralization against nirsevimab-resistant RSV (搜索) variants.
The company plans to advance VBY329 (搜索) toward IND readiness in the second half of 2026 for pediatric RSV (搜索) prophylaxis in a market expected to reach $3-4 billion annually by 2030.
VBY329 (搜索) was developed using Invivyd's proprietary antibody discovery platform and targets RSV (搜索) prevention in newborns, infants, and children under 24 months.
Invivyd, Inc. (Nasdaq: IVVD) has announced the selection of VBY329 (搜索), a potentially best-in-class monoclonal antibody candidate designed to prevent Respiratory Syncytial Virus (搜索) (RSV (搜索)) infections in newborns, infants, and children. The investigational antibody was generated using Invivyd's proprietary antibody discovery technology platform and represents a significant advancement in pediatric RSV prophylaxis.
Superior Potency Against RSV Variants
VBY329 (搜索) demonstrates substantial improvements over current standard of care treatments in laboratory testing. The candidate shows 1.5-fold greater antiviral potency on average than nirsevimab and 1.2-fold greater potency than clesrovimab against established authentic RSV (搜索) strains representing circulating variants.
Most notably, VBY329 (搜索) exhibits up to approximately 500-fold greater enhanced neutralization activity against RSV F protein (搜索) variants resistant to nirsevimab in pseudovirus assays. These assays reflect contemporary, circulating, nirsevimab-resistant variants associated with various RSV (搜索) A and B strains, addressing a critical gap in current treatment options.
"Following a screen that required greater resistance to variation than can be seen with class-leader nirsevimab, we have also achieved a major step change in average product potency compared to nirsevimab and clesrovimab," commented Robert Allen, Ph.D., Chief Scientific Officer of Invivyd. "These biophysical properties are understood to predict the extent of protection from lower respiratory tract infection following from RSV (搜索) infection in babies, as well as expanding the duration of likely protection."
Extended Protection Window
The antibody candidate incorporates half-life extension technology and biophysical properties expected to confer equivalent or greater in vivo half-life compared to nirsevimab and clesrovimab. Combined with its higher potency, these characteristics may expand the protective window of VBY329 (搜索) compared to standard of care treatments.
VBY329 (搜索)'s development followed a rigorous discovery strategy that required demonstration of differential binding activity against pre-fusion stabilized F proteins from RSV (搜索)-A2 and RSV-B313726, as well as proteins encoding resistance determinants to nirsevimab. The candidate also demonstrated improved neutralization potency within a pseudovirus panel representing this collection of variants.
Development Timeline and Market Opportunity
Invivyd expects to advance VBY329 (搜索) toward IND readiness in the second half of 2026 for development in pediatric RSV (搜索) prophylaxis. The company is moving the candidate into IND-enabling processes and plans to present in vitro VBY329 data at a future medical congress.
The pediatric RSV (搜索) prophylaxis market represents a significant commercial opportunity, described as a blockbuster pharmaceutical market in 2024 that is expected to grow to $3-4 billion in annual revenues globally by 2030. RSV is a common respiratory illness and the leading cause of hospitalization for infants in the United States.
"RSV (搜索) prophylaxis among babies and children under 24 months is a blockbuster, rapidly growing pharmaceutical market that frees our youngest, most vulnerable Americans, including newborns, from a high-burden pathogen, all without requiring the immune stimulation of a vaccine," noted Marc Elia, Chairman of the Invivyd Board of Directors.
Broader Pipeline Development
Beyond VBY329 (搜索), Invivyd continues to investigate additional monoclonal antibodies through its proprietary technology platform. The company's additional discovery efforts focus on ultra-long half-life RSV (搜索) antibodies with the aim of developing a candidate RSV vaccine-alternative for elderly and immunocompromised populations.
The company also continues to explore monoclonal antibodies for protection and treatment of other important infectious diseases, such as measles, among vulnerable populations. Invivyd previously received emergency use authorization from the U.S. FDA in March 2024 for a monoclonal antibody in its pipeline of innovative antibody candidates.
Monoclonal antibodies have served vulnerable young children and their care teams for almost 30 years, providing a model for other infectious diseases where populations would benefit from robust protection beyond the capabilities of a vaccine.