delNS1 H5N1

delNS1 H5N1 is a live attenuated intranasal vaccine candidate for the prevention of highly pathogenic avian influenza A (H5N1) infection. It is engineered by deleting the nonstructural protein 1 (NS1) gene from the influenza virus backbone, rendering it replication-deficient and unable to antagonize host interferon responses. This deletion enhances safety while maintaining immunogenicity. The vaccine induces robust mucosal and systemic immunity—including neutralizing antibodies, mucosal IgA, and T-cell responses—after a single intranasal dose in animal models such as mice, ferrets, macaques, and hamsters. It provides cross-protection against diverse clades of H5 viruses and demonstrates accelerated viral clearance or complete protection after one or two doses in preclinical studies[2][4][5]. Developed using an influenza virus vector-based platform by teams at HKU (University of Hong Kong) and CVVT (China Veterinary Vaccine Technology), delNS1 H5N1 is positioned as a rapid-response pandemic preparedness tool due to its single-dose efficacy and ability to induce strong upper respiratory tract immunity[4][5].

Other names

VN1203ΔNS1ΔNS1 H5N1 vaccine candidate