• Vaccine Name: D46/NS2/N/ΔM2-2-HindIII
• Target Pathogen: Human Respiratory Syncytial Virus
• Target Disease: Respiratory tract disease
• Manufacturer: Charles river Laboratories
• Type: Live, attenuated vaccine
• Status: Licensed
• Host Species for Licensed Use: Human
• M2-2 gene engineering:
  • Type: Deletion
  • Description: (McFarland et al., 2020)The vaccine uses backbone of LId/M2-2 vaccine but has a 234 nucleotide M2-2 deletion with the same structure as in MEDI/m2-2
  • Detailed Gene Information: Click Here.
• Immunization Route: intranasal immunization
• Description: (McFarland et al., 2020)The vaccine, D46/NS2/N/ΔM2-2-HindIII, is a cDNA-derived version of RSV subgroup A, strain A2. In addition, D46/NS2/N/ΔM2-2-HindIII has the MEDI/ΔM2-2 assignments at the only 2 amino acid positions that differ between MEDI/ΔM2-2 and LID/ΔM2-2. D46/NS2/N/ΔM2-2-HindIII contains the complete 112-nucleotide 3’ noncoding region of the SH gene that is present in biological RSV A2 but was deleted in LID/ΔM2-2. D46/NS2/N/ΔM2-2-HindIII was recovered from cDNA in qualified Vero cells.

Human Response

• Host age: (McFarland et al., 2020) Children greater than 6 months and less than 25 months of age.
• Host gender: (McFarland et al., 2020) Male and Female
• Vaccination Protocol: he study included children ≥6 and <25 months of age who were healthy, had no current or past lung disease, and were RSV seronegative at screening (McFarland et al., 2020)
• Side Effects: During the 28 days after inoculation, mild upper respiratory tract and/or febrile events occurred in both vaccine and placebo recipients, with 76%. All respiratory symptoms in both groups were grade 1. Grade 2 fever occurred in 1 vaccinee and 1 placebo recipient. Of the 16 vaccinees with respiratory or febrile illness, illness was concurrent with vaccine alone detected in NW specimens in 12, vaccine plus rhinovirus in 2, vaccine plus rhinovirus and adenovirus in 1, and parainfluenza type 4 and no vaccine virus in 1. (McFarland et al., 2020)
• Efficacy: (McFarland et al., 2020) When administered to RSV-naive 6–24 month-old infants and children, the RSV D46/NS2/N/ΔM2-2-HindIII candidate vaccine was well tolerated, was highly infectious (100% of participants had evidence of vaccine shedding and/or a serum RSV antibody response), and resulted in excellent induction of serum RSV-specific antibodies, including neutralizing antibodies.
• Description: (McFarland et al., 2020)The D46/NS2/N/ΔM2-2-HindIII vaccine had excellent infectivity and generated robust neutralizing antibody and anti-RSV F protein IgG responses.