Vivaldi Biosciences’ Universal Influenza Vaccine Shows Potential to Block Virus Transmission and Disease Spread
Study Results to be Presented at World Vaccine Congress
FORT COLLINS, Colorado and VIENNA, Austria – April 17, 2025 – Vivaldi Biosciences Inc., a clinical-stage biotechnology company developing nasal spray vaccines for viral respiratory diseases, will present data on the potential of its DeltaFLU universal influenza vaccine to block virus transmission at the World Vaccine Congress in Washington, DC on April 24.
Amy Aspelund, Vice President of Research and Development at Vivaldi Biosciences, will present data at the World Vaccine Congress showing that immunization with DeltaFLU blocks transmission of highly divergent influenza type A and type B viruses. The studies were conducted in ferrets, a well-characterized animal model of influenza infection and immunity in humans.
A universal influenza vaccine that both protects against all influenza virus strains and blocks transmission would be a significant advance in preventing influenza and reducing the disease burden, especially in the event of a pandemic. Influenza viruses are transmitted from an infected to a susceptible person mainly by airborne droplets produced by sneezing or coughing. An infected individual can spread influenza even before symptoms of illness begin. Influenza can spread rapidly in settings where people are in close proximity. Seasonal influenza infects up to 10% of adults and 30% of children worldwide every year, leading to millions of cases of severe illness and up to 650,000 deaths annually. An influenza pandemic could cause millions of deaths.
Vivaldi is developing DeltaFLU to protect against all influenza virus strains that cause disease in humans: all seasonal influenza type A and B strains, and emerging influenza virus strains with pandemic potential.
DeltaFLU vaccine strains have been successfully evaluated in four clinical trials. Additional Phase 1 and Phase 1/2 studies of DeltaFLU, funded by the NIAID and European Union, are scheduled for 2025. An EU-funded Phase 2 clinical challenge study planned for 2027. The ferret transmission studies confirmed previous findings showing DeltaFLU induces a broad immune response against influenza type A groups 1 and 2 viruses and type B viruses. The studies also confirmed earlier work showing that DeltaFLU protects immunized ferrets against challenge with broadly divergent type A and B strains, i.e., universal protection.
Administered as a nasal spray, DeltaFLU is composed of genetically attenuated influenza vaccine strains from which the NS1 gene is deleted. Deletion of NS1 results in the ability of DeltaFLU to induce interferon, conferring a self-adjuvant effect and activating multiple mechanisms of the immune response, including broadly cross-neutralizing antibodies in the nasal passages, systemic antibodies and T cells. The rapid immune response in the nasal passages creates a first line of defense at the point of entry of infectious viruses. Distinct from live attenuated influenza vaccines licensed and in development, DeltaFLU vaccine strains are replication-deficient. DeltaFLU vaccine strains do not form viral progeny and there is no detectable shedding of vaccine virus from recipients.
About Vivaldi Biosciences
Vivaldi is developing intranasal vaccines for superior protection against respiratory diseases. The company’s clinical-stage vaccines are the DeltaFLU universal influenza vaccine, for protection against all influenza A and B strains; and DelNS1 H5N1, a Phase 2-ready vaccine for protection against highly pathogenic influenza H5N1 strains with pandemic potential. The company’s Delta-19 combination vaccine for Covid-19 and influenza is in preclinical development. Vivaldi’s Vero cell-based vaccine manufacturing system uses patented advances in production and purification for high yields and excellent purity. Vivaldi is a venture-backed company with operations at the Research Innovation Center at Colorado State University, Fort Collins, Colorado, and in Vienna, Austria. NGN Capital LLC is the company’s lead investor. Learn more at www.vivaldibiosciences.com. Connect with Vivaldi Biosciences on Linkedin and Twitter.
Contact
Bill Wick, CEO, Vivaldi Biosciences
Tel: +1 650-400-8915
bill.wick@vivaldibiosciences.com