Extended antigen sparing potential of AS03-adjuvanted pandemic H1N1 vaccines in children, and immunological equivalence of two formulations of AS03-adjuvanted H1N1 vaccines: results from two randomised trials

Table 4 Study in adults: haemagglutinin inhibition (HI) antibodies to A/California/7/2009 (H1N1)v-like strain after vaccination (ATP cohorts for immunogenicity and persistence)

Group	Time	N	Seroconversion rate		Seroconversion factor		Seroprotection rate
	point		%	(95% CI)	Ratio	(95% CI)	%≥1:40	(95% CI)
Q-Pan	Pre	164	-	-	-	-	13.4	(8.6; 19.6)
	Day 21	164	93.9	(89.1; 97.0)	32.0	(26.5; 38.6)	97.6	(93.9; 99.3)
	Day 42	155	98.7	(95.4; 99.8)	63.2	(52.6; 75.9)	100	(97.6; 100)
	Month 6	154	91.6	(86.0; 95.4)	21.7	(18.1; 25.9)	97.4	(93.5; 99.3)
	Month 12	146	72.6	(64.6; 79.7)	11.0	(9.1; 13.3)	82.9	(75.8; 88.6)
D-Pan	Pre	164	-	-	-	-	11.6	(7.1; 17.5)
	Day 21	164	97.6	(93.9; 99.3)	41.5	(34.3; 50.2)	100	(97.8; 100)
	Day 42	155	99.4	(96.5; 100)	63.0	(52.2; 76.1)	100	(97.6; 100)
	Month 6	156	92.3	(86.9; 96.0)	22.0	(18.5; 26.1)	96.8	(92.7; 99.0)
	Month 12	144	75.7	(67.9; 82.4)	11.0	(9.2; 13.2)	84.0	(77.0; 89.6)

N number of subjects with available results (for seroconversion rate and seroconversion factor, N - the number of subjects with pre- and post-vaccination results available), % - percentage of subjects; 95% CI - 95% confidence interval; Seroconversion: For initially seronegative subjects (i.e., HI titres <1:10), antibody titre ≥ 1:40 after vaccination. For initially seropositive subjects, post-vaccination HI titre ≥ 4 fold the pre-vaccination antibody titre. Seroconversion Factor -mean[log₁₀(post-vaccination GMT/pre vaccination GMT)]; Pre = prior to vaccination, Day 21 etc- 21 days post vaccination. CBER Criteria were fulfilled if: the lower limit of the 95% CI for SCR was >40%, and the lower limit of the 95% CI for % ≥1:40 was >70%. CHMP Criteria were fulfilled if: the point estimate for SCR was > 40% and, the post-vaccination point estimate for % ≥1:40 was >70% and, the point estimate for SCF was > 2.5. See Table 1 for details of treatment groups.

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