Immunogenicity and safety of a novel liposomal influenza subunit vaccine (INFLUSOME-VAC) in young adults.
Influenza and its complications account for substantial morbidity and mortality among young adults and especially among the elderly. In young adults, immunization provides 70-90% protection, while among the elderly the vaccine may be only 30-40% effective; hence the need for new, more immunogenic vaccines. We compared the safety and immunogenicity of a novel IL-2-supplemented liposomal influenza vaccine (designated INFLUSOME-VAC) with that of a commercial subunit vaccine and a commercial split virion vaccine in young adults (mean age 28 years) in the winter of 1999-2000. Seventy-three healthy young adults were randomly assigned to be vaccinated intramuscularly with the following: a commercial subunit vaccine (n = 17, group A), INFLUSOME-VAC (n = 36, group B), and a commercial split virion vaccine (n = 20, group C). The three vaccines contained equal amounts of hemagglutinin (approximately 15 microg each) from the strains A/Sydney (H3N2), A/Beijing (H1N1), and B/Yamanashi. INFLUSOME-VAC induced higher geometric mean HI titers and higher-fold increases in HI titers against all three strains, compared with the two commercial vaccines. In addition, seroconversion rates for the A/Sydney and B/Yamanashi strains were significantly higher (P < 0.05) compared with the split virion vaccine, and significantly higher for the three strains compared with the subunit vaccine (69-97% vs 35-65%, P < or = 0.02). Moreover, the anti-neuraminidase response was significantly greater (P = 0.05) in group B vs group A. INFLUSOME-VAC caused mild local pain at the injection site in a significantly higher proportion of the vaccinees (83%). Thus, INFLUSOME-VAC is an immunogenic and safe vaccine in young adults.
Ben-Yehuda
Arie
A
Department of Internal Medicine, Hebrew University-Hadassah Medical School and Hadassah Hospital, Jerusalem, Israel. benyehuda@hadassah.org.il
Joseph
Aviva
A
Zeira
Evelyne
E
Even-Chen
Simcha
S
Louria-Hayon
Igal
I
Babai
Ilan
I
Zakay-Rones
Zichria
Z
Greenbaum
Evgenia
E
Barenholz
Yechezkel
Y
Kedar
Eli
E
D000293:Adolescent; D000328:Adult; D000818:Animals; D005260:Female; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology; D006801:Humans; D009980:Influenza A virus / Q000276:immunology*; D009981:Influenza B virus / Q000276:immunology*; D007252:Influenza Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000276:immunology; D007251:Influenza, Human / Q000517:prevention & control*; D007376:Interleukin-2 / Q000235:genetics / Q000276:immunology; D008081:Liposomes / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009439:Neuraminidase / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology
D019267:Hemagglutinin Glycoproteins, Influenza Virus; D007252:Influenza Vaccines; D007376:Interleukin-2; D008081:Liposomes; D011994:Recombinant Proteins; D009439:Neuraminidase