Standardization of the methods and reference materials used to assess virus content in varicella vaccines

Table 2 Results of the collaborative study using the vaccine sample (Suduvax (Green Cross Corp., Korea) and Varilrix (GlaxoSmithKline, Belgium)). The results of the collaborative study by method were compared to the virus content (titer) of the vaccine (titer unit: log₁₀PFU/ dose)

Vaccine	Laboratory^a	Method	Result
Vaccine	Laboratory^a	Method	GMT^b	95 % C.I.^c	P-value^*
Suduvax	A	PSM^d	3.53	3.49, 3.57	0.8661
	A	AOM^e	3.54	3.50, 3.58	0.8661
	B	PSM^d	4.01	3.98, 4.05	<.0001
	B	AOM^e	3.28	3.25, 3.32	<.0001
	C	PSM^d	3.74	3.67, 3.81	0.4627
	C	AOM^e	3.70	3.64, 3.78	0.4627
	D	PSM^d	3.68	3.66, 3.70	0.3658
	D	AOM^e	3.70	3.68, 3.71	0.3658
Varilrix	A	PSM^d	3.86	3.82, 3.91	0.5064
	A	AOM^e	3.88	3.84, 3.93	0.5064
	B	PSM^d	4.17	4.14, 4.20	<.0001
	B	AOM^e	3.46	3.43, 3.49	<.0001
	C	PSM^d	3.75	3.68, 3.82	<.0001
	C	AOM^e	4.02	3.96, 4.10	<.0001
	D	PSM^d	3.70	3.68, 3.72	<.0001
	D	AOM^e	3.76	3.74, 3.78	<.0001

^aLaboratory: one of the participating laboratories, the National Center for Lot Release, Green Cross Corp. (Korea), SK Chemicals (Korea), and Korea Vaccine Co. (Korea) (in randomized order)
^b GMT, Geometric mean titer
^c 95 % C.I., 95 % confidence interval
^d PSM, Plaque staining method
^d AOM, Agar overlay method
^* P-value: ANOVA test

ISSN: 1743-422X