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Live-Attenuated Respiratory Syncytial Virus Vaccine With Deletion of RNA Synthesis Regulatory Protein M2-2 and Cold Passage Mutations Is Overattenuated.

ABSTRACT: Background:The live respiratory syncytial virus (RSV) candidate vaccine LIDcp?M2-2 is attenuated through deletion of M2-2 and 5 cold-passage mutations. Methods:RSV-seronegative children aged 6-24 months received a single intranasal dose of 105 plaque-forming units (PFU) of LIDcp?M2-2 or placebo. RSV serum antibodies, vaccine infectivity, and reactogenicity were assessed. Results:Four of 11 (36%) vaccinees shed vaccine virus with median peak titers of 1.6 log10 PFU/mL by quantitative culture and 4.5 log10 copies/mL by polymerase chain reaction; 45% had ?4-fold rise in serum-neutralizing antibodies. Respiratory symptoms or fever were common in vaccinees (64%) and placebo recipients (6/6, 100%). Conclusions:RSV LIDcp?M2-2 is overattenuated. Clinical Trial Numbers.?NCT02890381, NCT02948127.

SUBMITTER: Cunningham CK

PROVIDER: S-EPMC6559275 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Live-Attenuated Respiratory Syncytial Virus Vaccine With Deletion of RNA Synthesis Regulatory Protein M2-2 and Cold Passage Mutations Is Overattenuated.

Cunningham Coleen K CK Karron Ruth R Muresan Petronella P McFarland Elizabeth J EJ Perlowski Charlotte C Libous Jennifer J Thumar Bhagvanji B Gnanashanmugam Devasena D Moye Jack J Schappell Elizabeth E Barr Emily E Rexroad Vivian V Aziz Mariam M Deville Jaime J Rutstein Richard R Yang Lijuan L Luongo Cindy C Collins Peter P Buchholz Ursula U

Open forum infectious diseases 20190506 6

<h4>Background</h4>The live respiratory syncytial virus (RSV) candidate vaccine LIDcpΔM2-2 is attenuated through deletion of M2-2 and 5 cold-passage mutations.<h4>Methods</h4>RSV-seronegative children aged 6-24 months received a single intranasal dose of 10<sup>5</sup> plaque-forming units (PFU) of LIDcpΔM2-2 or placebo. RSV serum antibodies, vaccine infectivity, and reactogenicity were assessed.<h4>Results</h4>Four of 11 (36%) vaccinees shed vaccine virus with median peak titers of 1.6 log<sub> ...[more]

PMID: 31211158

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Dataset Information

Live-Attenuated Respiratory Syncytial Virus Vaccine With Deletion of RNA Synthesis Regulatory Protein M2-2 and Cold Passage Mutations Is Overattenuated.

Publications

Live-Attenuated Respiratory Syncytial Virus Vaccine With Deletion of RNA Synthesis Regulatory Protein M2-2 and Cold Passage Mutations Is Overattenuated.

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