tetano
Editor, Senior Moderator
J Infect Dis. 2015 Feb 3. pii: jiv056. [Epub ahead of print]
[h=1]Safety and Immunogenicity of a Subvirion Monovalent Unadjuvanted Inactivated Influenza A/H3N2 Variant (H3N2v) Vaccine in Healthy Persons≥18 Years Old.[/h] Keitel WA, Jackson LA, Edupuganti S, Winokur PL, Mulligan MJ, Thornburg NJ, Patel SM, Rouphael NG, Lai L, Bangaru S, McNeal MM, Bellamy AR, Hill HR; for the VTEU H3N2v Vaccine Study Work Group.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Variant influenza A/H3N2 viruses (H3N2v) have transmitted recently from pigs to humans in the US. Vaccines strategies are needed.
[h=4]METHODS:[/h] Healthy adults received 2 doses of subvirion H3N2v vaccine [15 ?g of hemagglutinin/dose] 21 days apart in this open-label trial. Serum hemagglutination inhibition (HAI) and neutralizing (Neut) antibody (Ab) titers were measured before and 8 and 21 days after each dose. Memory B cell (MBC) responses were assessed.
[h=4]RESULTS:[/h] Vaccine was well tolerated. 40% of subjects had an HAI Ab titer ≥40 prevaccination. 87% (CI: 79-93%) and 73% (CI: 63-81%) of subjects 18-64 y.o. (N=98) and ≥65 y.o. (N=90), respectively, had an HAI titer ≥40 21 days after dose 1 (p=0.01); 51% (CI: 0.41-0.61%) and 52% (0.41-.62%) of younger and older subjects developed ≥4-fold rises in titer, respectively (p=NS). Neut Ab response patterns were similar. GMTs were higher in younger subjects. Dose 2 provided no significant enhancement in responses. Cross-reactive MBCs were detected prevaccination and expanded after vaccination. Preexisting H3N2v-specific MBCs positively correlated with early increases in vaccine-induced Ab.
[h=4]CONCLUSIONS:[/h] In most healthy adults, one 15 ?g dose of vaccine elicited levels of HAI antibodies associated with protection. Studies in children and the elderly are indicated to define their immunization needs.
? The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
PMID: 25649171 [PubMed - as supplied by publisher]
[h=1]Safety and Immunogenicity of a Subvirion Monovalent Unadjuvanted Inactivated Influenza A/H3N2 Variant (H3N2v) Vaccine in Healthy Persons≥18 Years Old.[/h] Keitel WA, Jackson LA, Edupuganti S, Winokur PL, Mulligan MJ, Thornburg NJ, Patel SM, Rouphael NG, Lai L, Bangaru S, McNeal MM, Bellamy AR, Hill HR; for the VTEU H3N2v Vaccine Study Work Group.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Variant influenza A/H3N2 viruses (H3N2v) have transmitted recently from pigs to humans in the US. Vaccines strategies are needed.
[h=4]METHODS:[/h] Healthy adults received 2 doses of subvirion H3N2v vaccine [15 ?g of hemagglutinin/dose] 21 days apart in this open-label trial. Serum hemagglutination inhibition (HAI) and neutralizing (Neut) antibody (Ab) titers were measured before and 8 and 21 days after each dose. Memory B cell (MBC) responses were assessed.
[h=4]RESULTS:[/h] Vaccine was well tolerated. 40% of subjects had an HAI Ab titer ≥40 prevaccination. 87% (CI: 79-93%) and 73% (CI: 63-81%) of subjects 18-64 y.o. (N=98) and ≥65 y.o. (N=90), respectively, had an HAI titer ≥40 21 days after dose 1 (p=0.01); 51% (CI: 0.41-0.61%) and 52% (0.41-.62%) of younger and older subjects developed ≥4-fold rises in titer, respectively (p=NS). Neut Ab response patterns were similar. GMTs were higher in younger subjects. Dose 2 provided no significant enhancement in responses. Cross-reactive MBCs were detected prevaccination and expanded after vaccination. Preexisting H3N2v-specific MBCs positively correlated with early increases in vaccine-induced Ab.
[h=4]CONCLUSIONS:[/h] In most healthy adults, one 15 ?g dose of vaccine elicited levels of HAI antibodies associated with protection. Studies in children and the elderly are indicated to define their immunization needs.
? The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
PMID: 25649171 [PubMed - as supplied by publisher]