tetano
Editor, Senior Moderator
Vaccine. 2019 Jul 30. pii: S0264-410X(19)31006-0. doi: 10.1016/j.vaccine.2019.07.085. [Epub ahead of print]
[h=1]Safety and immunogenicity of unadjuvanted subvirion monovalent inactivated influenza H3N2 variant (H3N2v) vaccine in children and adolescents.[/h] Munoz FM[SUP]1[/SUP], Anderson EJ[SUP]2[/SUP], Bernstein DI[SUP]3[/SUP], Harrison CJ[SUP]4[/SUP], Pahud B[SUP]4[/SUP], Anderson E[SUP]5[/SUP], Creech CB[SUP]6[/SUP], Berry AA[SUP]7[/SUP], Kotloff KL[SUP]7[/SUP], Walter EB[SUP]8[/SUP], Atmar RL[SUP]9[/SUP], Bellamy AR[SUP]10[/SUP], Chang S[SUP]11[/SUP], Keitel WA[SUP]9[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVE:[/h] In response to the emergence of influenza viruses with pandemic potential, we evaluated a swine-origin influenza A/H3N2 variant (H3N2v) vaccine in children.
[h=4]STUDY DESIGN:[/h] This multicenter phase II open-label study assessed the safety and immunogenicity of two doses, 21 days apart, of investigational unadjuvanted subvirion monovalent inactivated H3N2v vaccine administered via intramuscular injection. Children 6-35 months of age received 7.5mcg or 15mcg of hemagglutinin (HA)/dose; children 3-17 years of age received 15mcg HA/dose. Safety and reactogenicity were assessed by measuring the occurrence of solicited injection site and systemic reactions in the 7 days after each vaccination; adverse events were assessed for 42 days and serious adverse events for 7 months after the first vaccination. Immunogenicity was evaluated by measuring hemagglutination inhibition (HAI) and neutralizing (Neut) antibodies to H3N2v prior to and 21 days after each vaccination. Cross-reactivity against seasonal H3N2 strains was evaluated.
[h=4]RESULTS:[/h] The H3N2v vaccine was well tolerated. Transient mild to moderate injection site tenderness, pain and erythema was observed, with the most commonly reported systemic reactogenicity being irritability in children 6-35 months, and headache and fatigue in children 9-17 years old. Children 6-35 months old, whether they received 7.5mcg or 15mcg/dose, had low HAI and Neut antibody responses after two doses compared to older children. Children under 9 years of age required two doses of vaccine to demonstrate a response, while 9-17 year olds responded well after one dose. Previous influenza vaccination and older age were associated with higher immune responses to H3N2v vaccine. Children 9-17 years of age also developed cross-reactive antibodies against recent seasonal H3N2 influenza viruses.
[h=4]CONCLUSION:[/h] The H3N2v vaccine was safe and immunogenic in children and adolescents. Age-related increases in immunogenicity against H3N2v and seasonal H3N2 viruses were observed, suggesting prior priming via infection and/or immunization. Clinical trial registry: The trial is registered with clinicaltrial.gov: NCT02100436.
Copyright ? 2019 Elsevier Ltd. All rights reserved.
[h=4]KEYWORDS:[/h] Adolescents; Children; Cross-reactive antibodies; H3N2 variant; Immunogenicity; Influenza; Safety
PMID: 31375440 DOI: 10.1016/j.vaccine.2019.07.085
[h=1]Safety and immunogenicity of unadjuvanted subvirion monovalent inactivated influenza H3N2 variant (H3N2v) vaccine in children and adolescents.[/h] Munoz FM[SUP]1[/SUP], Anderson EJ[SUP]2[/SUP], Bernstein DI[SUP]3[/SUP], Harrison CJ[SUP]4[/SUP], Pahud B[SUP]4[/SUP], Anderson E[SUP]5[/SUP], Creech CB[SUP]6[/SUP], Berry AA[SUP]7[/SUP], Kotloff KL[SUP]7[/SUP], Walter EB[SUP]8[/SUP], Atmar RL[SUP]9[/SUP], Bellamy AR[SUP]10[/SUP], Chang S[SUP]11[/SUP], Keitel WA[SUP]9[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]OBJECTIVE:[/h] In response to the emergence of influenza viruses with pandemic potential, we evaluated a swine-origin influenza A/H3N2 variant (H3N2v) vaccine in children.
[h=4]STUDY DESIGN:[/h] This multicenter phase II open-label study assessed the safety and immunogenicity of two doses, 21 days apart, of investigational unadjuvanted subvirion monovalent inactivated H3N2v vaccine administered via intramuscular injection. Children 6-35 months of age received 7.5mcg or 15mcg of hemagglutinin (HA)/dose; children 3-17 years of age received 15mcg HA/dose. Safety and reactogenicity were assessed by measuring the occurrence of solicited injection site and systemic reactions in the 7 days after each vaccination; adverse events were assessed for 42 days and serious adverse events for 7 months after the first vaccination. Immunogenicity was evaluated by measuring hemagglutination inhibition (HAI) and neutralizing (Neut) antibodies to H3N2v prior to and 21 days after each vaccination. Cross-reactivity against seasonal H3N2 strains was evaluated.
[h=4]RESULTS:[/h] The H3N2v vaccine was well tolerated. Transient mild to moderate injection site tenderness, pain and erythema was observed, with the most commonly reported systemic reactogenicity being irritability in children 6-35 months, and headache and fatigue in children 9-17 years old. Children 6-35 months old, whether they received 7.5mcg or 15mcg/dose, had low HAI and Neut antibody responses after two doses compared to older children. Children under 9 years of age required two doses of vaccine to demonstrate a response, while 9-17 year olds responded well after one dose. Previous influenza vaccination and older age were associated with higher immune responses to H3N2v vaccine. Children 9-17 years of age also developed cross-reactive antibodies against recent seasonal H3N2 influenza viruses.
[h=4]CONCLUSION:[/h] The H3N2v vaccine was safe and immunogenic in children and adolescents. Age-related increases in immunogenicity against H3N2v and seasonal H3N2 viruses were observed, suggesting prior priming via infection and/or immunization. Clinical trial registry: The trial is registered with clinicaltrial.gov: NCT02100436.
Copyright ? 2019 Elsevier Ltd. All rights reserved.
[h=4]KEYWORDS:[/h] Adolescents; Children; Cross-reactive antibodies; H3N2 variant; Immunogenicity; Influenza; Safety
PMID: 31375440 DOI: 10.1016/j.vaccine.2019.07.085