1. Immunogenicity of a Third Scheduled Dose of Rotarix in Australian Indigenous Infants: A Phase IV, Double-blind, Randomized, Placebo-Controlled Clinical Trial
- Author
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Middleton, BF, Danchin, M, Jones, MA, Leach, AJ, Cunliffe, N, Kirkwood, CD, Carapetis, J, Gallagher, S, Kirkham, L-A, Granland, C, McNeal, M, Marsh, JA, Waddington, CS, Snelling, TL, Middleton, BF, Danchin, M, Jones, MA, Leach, AJ, Cunliffe, N, Kirkwood, CD, Carapetis, J, Gallagher, S, Kirkham, L-A, Granland, C, McNeal, M, Marsh, JA, Waddington, CS, and Snelling, TL
- Abstract
BACKGROUND: Rotarix (GlaxoSmithKline) oral rotavirus vaccine is licensed as 2 doses in the first 6 months of life. In settings with high child mortality rates, clinical protection conferred by 2 doses of Rotarix is reduced. We assessed vaccine immune response when an additional dose of Rotarix was given to Australian Aboriginal children 6 to <12 months old. METHODS: ORVAC is a 2-stage, double-blind, randomized, placebo-controlled trial. Australian Aboriginal children 6 to <12 months old who had received 1 or 2 prior doses of Rotarix rotavirus vaccine were randomized 1:1 to receive an additional dose of Rotarix or matched placebo. The primary immunological end point was seroresponse defined as an anti-rotavirus immunoglobulin A level ≥20 AU/mL, 28-56 days after the additional dose of Rotarix or placebo. RESULTS: Between March 2018 and August 2020, a total of 253 infants were enrolled. Of these, 178 infants (70%) had analyzable serological results after follow-up; 89 were randomized to receive Rotarix, and 89 to receive placebo. The proportion with seroresponse was 85% after Rotarix compared with 72% after placebo. There were no occurrences of intussusception or any serious adverse events. CONCLUSIONS: An additional dose of Rotarix administered to Australian Aboriginal infants 6 to <12 months old increased the proportion with a vaccine seroresponse. CLINICAL TRIALS REGISTRATION: NCT02941107.
- Published
- 2022