TY - JOUR
T1 - Immunogenicity and reactogenicity following MMR vaccination in 5–7-month-old infants
T2 - a double-blind placebo-controlled randomized clinical trial in 6540 Danish infants
AU - Vittrup, Dorthe Maria
AU - Jensen, Andreas
AU - Sørensen, Jesper Kiehn
AU - Zimakoff, Anne Cathrine
AU - Malon, Michelle
AU - Charabi, Salma
AU - Johansen, Marie Ryberg
AU - Simões, Eric A.F.
AU - Kirkby, Nikolai Søren
AU - Buus, Søren
AU - Svensson, Jannet
AU - Stensballe, Lone Graff
N1 - Publisher Copyright:
© 2024 The Authors
PY - 2024
Y1 - 2024
N2 - Background: Measles is a highly contagious viral disease. Vaccinated mothers transfer fewer antibodies during pregnancy, resulting in shortened infant immunity. Earlier primary vaccination might avert the gap in protection. Methods: Healthy 5–7-month-old Danish infants were assigned in a 1:1 ratio to M-M-RVaxPro or placebo (solvent) in a double-blind, randomized trial between April 15, 2019 and November 1, 2021 (ClinicalTrials.gov NCT03780179, EudraCT 2016-001901-18). Eligibility criteria were birth weight >1000 g and gestational age ≥32 weeks. Immunogenicity was measured by plaque reduction neutralization test (PRNT) and IgG ELISA before intervention, four weeks after intervention and routine MMR. Reactogenicity data were collected for six weeks and measured by hazard ratios (HR). Findings: 647 and 6540 infants participated in the immunogenicity and reactogenicity study, respectively; 87% and 99% completed follow-up. After early MMR, seroprotection rates (SPRs) were 47% (13%) in measles PRNT; 28% (2%), 57% (8%) in mumps and rubella IgG (placebo). For measles PRNT, geometric mean ratio was 4.3 (95% CI: 3.4–5.3) between randomization groups after intervention and 1.5 (95% CI: 1.3–1.9) after routine MMR. Reactogenicity was independent of randomization (HR, 1.0; 95% CI: 0.9–1.1). Severe adverse events occurred in 25 infants (HR, 1.8; 95% CI: 0.8–4.0); none deemed vaccine related. Interpretation: Early MMR elicited low SPRs but did not negatively impact short-term responses to a subsequent MMR. MMR at 5–7 months was safe and not associated with higher rates of reactogenicity than placebo. Funding: Innovation Fund Denmark.
AB - Background: Measles is a highly contagious viral disease. Vaccinated mothers transfer fewer antibodies during pregnancy, resulting in shortened infant immunity. Earlier primary vaccination might avert the gap in protection. Methods: Healthy 5–7-month-old Danish infants were assigned in a 1:1 ratio to M-M-RVaxPro or placebo (solvent) in a double-blind, randomized trial between April 15, 2019 and November 1, 2021 (ClinicalTrials.gov NCT03780179, EudraCT 2016-001901-18). Eligibility criteria were birth weight >1000 g and gestational age ≥32 weeks. Immunogenicity was measured by plaque reduction neutralization test (PRNT) and IgG ELISA before intervention, four weeks after intervention and routine MMR. Reactogenicity data were collected for six weeks and measured by hazard ratios (HR). Findings: 647 and 6540 infants participated in the immunogenicity and reactogenicity study, respectively; 87% and 99% completed follow-up. After early MMR, seroprotection rates (SPRs) were 47% (13%) in measles PRNT; 28% (2%), 57% (8%) in mumps and rubella IgG (placebo). For measles PRNT, geometric mean ratio was 4.3 (95% CI: 3.4–5.3) between randomization groups after intervention and 1.5 (95% CI: 1.3–1.9) after routine MMR. Reactogenicity was independent of randomization (HR, 1.0; 95% CI: 0.9–1.1). Severe adverse events occurred in 25 infants (HR, 1.8; 95% CI: 0.8–4.0); none deemed vaccine related. Interpretation: Early MMR elicited low SPRs but did not negatively impact short-term responses to a subsequent MMR. MMR at 5–7 months was safe and not associated with higher rates of reactogenicity than placebo. Funding: Innovation Fund Denmark.
KW - Early immunization
KW - Immunogenicity
KW - Measles vaccination
KW - MMR
KW - Reactogenicity
U2 - 10.1016/j.eclinm.2023.102421
DO - 10.1016/j.eclinm.2023.102421
M3 - Journal article
C2 - 38292039
AN - SCOPUS:85182576412
VL - 68
JO - EClinicalMedicine
JF - EClinicalMedicine
SN - 2589-5370
M1 - 102421
ER -