Table 4.

Combined assessment of infliximab and anti-infliximab for people with loss of response receiving infliximab

Steenholdt et al 26	ADAbs+	ADAbs−	Total	Population and anti-TNFα therapy; tests
Anti-TNFα−	NOR=8	NOR=2	NOR=10	Failure on infliximab, continued failure or gain of response at 12 weeks; RIA. Prevalence of NOR=44.9%
	RESP=6	RESP=1	RESP=7
Anti-TNFα+	NOR=1	NOR=20	NOR=21
	RESP=3	RESP=28	RESP=31
Total	NOR=9	NOR=22	NOR=31
	RESP=9	RESP=29	RESP=38

The probability of a patient returning each of the four possible test result combinations was:

ADAbs+/anti-TNFα−, 0.203; ADAbs+/anti-TNFα+, 0.058; ADAbs−/anti-TNFα−, 0.00.043; ADAbs−/anti-TNFα+, 0.696.

The probabilities of failing to gain a response according to category of test result were 0.571, 0.250, 0.667 and 0.417, respectively.

ADAbs, antidrug antibodies; LOR, loss of response; RESP, responders; NOR, no regain of response; TNF, tumour necrosis factor.