Dataset Information

Evaluation of the Safety, Tolerability and Immunogenicity of ShigETEC, an Oral Live Attenuated Shigella-ETEC Vaccine in Placebo-Controlled Randomized Phase 1 Trial.

ABSTRACT: Shigella spp. and enterotoxigenic Escherichia coli (ETEC) cause high morbidity and mortality worldwide, yet no licensed vaccines are available to prevent corresponding infections. A live attenuated non-invasive Shigella vaccine strain lacking LPS O-antigen and expressing the ETEC toxoids, named ShigETEC was characterized previously in non-clinical studies. ShigETEC was evaluated in a two-staged, randomized, double-blind and placebo-controlled Phase I clinical trial. A single dose of increasing amounts of the vaccine was given to determine the maximum tolerated dose and increasing number of immunizations were administered with an interval based on the duration of shedding observed. Oral immunization with ShigETEC was well tolerated and safe up to 4-time dosing with 5 × 1010 colony forming units. ShigETEC induced robust systemic immune responses against the Shigella vaccine strain, with IgA serum antibody dominance, as well as mucosal antibody responses evidenced by specific IgA in stool samples and in ALS (Antibodies in Lymphocyte Supernatant). Anti- ETEC toxin responses were detected primarily in the 4-times immunized cohort and for the heat-labile toxin correlated with neutralizing capacity. ShigETEC is a promising vaccine candidate that is scheduled for further testing in controlled human challenge studies for efficacy as well as in children in endemic setting for safety and immunogenicity.

SUBMITTER: Girardi P

PROVIDER: S-EPMC8879453 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Evaluation of the Safety, Tolerability and Immunogenicity of ShigETEC, an Oral Live Attenuated <i>Shigella</i>-ETEC Vaccine in Placebo-Controlled Randomized Phase 1 Trial.

Girardi Petra P Harutyunyan Shushan S Neuhauser Irene I Glaninger Katharina K Korda Orsolya O Nagy Gábor G Nagy Eszter E Szijártó Valéria V Pall Denes D Szarka Krisztina K Kardos Gábor G Henics Tamás T Malinoski Frank J FJ

Vaccines 20220221 2

<h4>Background</h4><i>Shigella</i> spp. and enterotoxigenic <i>Escherichia coli</i> (ETEC) cause high morbidity and mortality worldwide, yet no licensed vaccines are available to prevent corresponding infections. A live attenuated non-invasive <i>Shigella</i> vaccine strain lacking LPS O-antigen and expressing the ETEC toxoids, named ShigETEC was characterized previously in non-clinical studies.<h4>Methods</h4>ShigETEC was evaluated in a two-staged, randomized, double-blind and placebo-controlle ...[more]

PMID: 35214798

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Dataset Information

Evaluation of the Safety, Tolerability and Immunogenicity of ShigETEC, an Oral Live Attenuated Shigella-ETEC Vaccine in Placebo-Controlled Randomized Phase 1 Trial.

Publications

Evaluation of the Safety, Tolerability and Immunogenicity of ShigETEC, an Oral Live Attenuated <i>Shigella</i>-ETEC Vaccine in Placebo-Controlled Randomized Phase 1 Trial.

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