TABLE 4.

Responses to 15-mer ELISPOT assays in subjects with baseline anti-Ad5 titers of ≤200 receiving the MRKAd5 trigene or MRKAd5 trivalent vaccine (stage IB)

Peptide pool antigen(s) and vaccinea	Wk 4			Wk 8			Wk 30			Wk 52
	No. of subjects	% Responding	GMb	No. of subjects	% Responding	GM	No. of subjects	% Responding	GM	No. of subjects	% Responding	GM
Gag
Placebo	4	0	12	4	0	27	3	0	27	3	0	42
MRKAd5 trigene	6	50	78	7	43	71	4	75	367	7	71	129
MRKAd5 trivalent	8	88	244	8	75	247	7	100	302	6	83	348
Pol
Placebo	4	0	26	4	0	51	3	0	66	3	0	111
MRKAd5 trigene	6	50	135	7	57	105	4	75	282	7	14	131
MRKAd5 trivalent	8	63	350	8	75	427	7	71	435	6	67	555
Nef
Placebo	4	0	9	4	0	23	3	0	24	3	0	46
MRKAd5 trigene	6	100	199	7	86	172	4	75	385	7	71	233
MRKAd5 trivalent	8	88	257	8	75	188	7	57	221	6	67	239
≥1 peptide pool
Placebo	4	0		4	0		3	0		3	0
MRKAd5 trigene	6	100		7	86		4	75		7	71
MRKAd5 trivalent	8	88		8	88		7	100		6	83
≥2 peptide pools
Placebo	4	0		4	0		3	0		3	0
MRKAd5 trigene	6	67		7	71		4	75		7	71
MRKAd5 trivalent	8	88		8	75		7	71		6	67
All 3 peptide pools
Placebo	4	0		4	0		3	0		3	0
MRKAd5 trigene	6	33		7	29		4	75		7	14
MRKAd5 trivalent	8	63		8	63		7	57		6	67

^aThe MRKAd5 trigene vaccine was given at 0.5×10¹⁰ vg/dose, and the MRKAd5 trivalent vaccine was given at 1.5×10¹⁰ vg/dose.

^bGM, geometric mean ELISPOT response, expressed as the number of spot-forming cells per 10⁶ peripheral blood mononuclear cells.