Table 2.

Immunogenicity profiles of avian H5N1 virus-based vaccines with and without adjuvants.

Manufacturer (trade name)	Antigen	HA dose (μg)	Seroconversion† without adjuvant (%)	Seroconversion with adjuvant (%)	Ref.
Sanofi Pasteur‡	Inactivated split virus	90‡	57		[28,72,73]
	A/Vietnam/1194/2004	45	41
		30	52	67 (alum)#
		15	24	86 (AF03)
		7.5	13	89 (AF03)
		3.8		81 (AF03)
		1.9		72 (AF03)
Novartis§	Inactivated subunit	45	29		[25,74,75]
	A/Vietnam/1203/2004	30	18	14 (alum)
		15	24	7 (alum)
		7.5	34	3 (alum)
	Inactivated subunit	30	18
	A/Vietnam/1203/2004	15	24	63 (MF59)
		7.5	34	23–73 (MF59)
		3.8		65 (MF59)
GSK§	Inactivated split virus	30	41	85 (AS03)	[76,77]
	A/Vietnam/1194/2004	15	35	96 (AS03)
		7.5	16	90 (AS03)
		3.8	4	84–94 (AS03)
CSL¶	Inactivated split virus	45		49 (alum)	[78]
	A/Vietnam/1194/2004	30		48 (alum)
		15		35 (alum)
		7.5		34 (alum)
Baxter§	Vero cell-derived inactivated whole virion	15	68††		[11,14]
	(A/Vietnam/1203/2004)	7.5	62
		3.8	41

Data are from studies in adult subjects, employing the same clade of H5N1 virus antigen and administered following two immunizations either 21 or 28 days apart. Direct comparisons are not possible due to differences in reagents and methodologies to determine HI titers. Ranges are provided in instances where referenced studies contain the same antigen dose level.

^†HA inhibition assays with titer ≥1:40 or ≥fourfold increase in hemagglutination inhibition titer.

^‡FDA approved.

^§EU approved.

^¶Australia approved.

^#No significant difference between non-alum vaccine group.

^††Calculated based on subjects achieving ≥1:20 using the microneutralization assay.

HA: Hemagglutinin; HI: Hemagglutination inhibition.