Table 5.

Efficacy results for RAS wild-type CRYSTAL, FIRE-3 and CALGB 80405 cetuximab trial patients, according to tumour location

	CRYSTAL					FIRE-3					CALGB 80405
	Right-sided tumours N=84		Left-sided tumours N=280			Right-sided tumours N=88			Left-sided tumours N=306		Right-sided tumours N=149		Left-sided tumours N=325
Parameter	FOLFIRI	FOLFIRI +cetux	FOLFIRI		FOLFIRI +cetux	FOLFIRI +bev		FOLFIRI +cetux	FOLFIRI +bev	FOLFIRI +cetux	CTa+bev	CTa+cetux	CTa+bev	CTa+cetux
	n = 51	n = 33	n = 138		n = 142	n = 50		n = 38	n = 149	n = 157	n = 78	n = 71	n = 152	n = 173
OS
Median, months	15.0	18.5	21.7		28.7	23.0		18.3	28.0	38.3	29.2	13.7	32.6	39.3
HR (95% CI)	1.08 (0.65–1.81)		0.65 (0.50–0.86)			1.31 (0.81–2.11)			0.63 (0.48–0.85)		1.36 (0.93–1.99)		0.77 (0.59–0.99)
P value	0.77		0.002			0.27			0.002		0.11b		0.05b
P value for interaction	0.09					0.01					0.02
PFS
Median, months	7.1	8.1	8.9		12.0	9.0		7.6	10.7	10.7	10.2	7.5	11.2	12.7
HR (95% CI)	0.87 (0.47–1.62)		0.50 (0.34–0.72)			1.44 (0.92–2.26)			0.90 (0.71–1.14)		1.64 (1.15–2.36)		0.84 (0.66–1.06)
P value	0.66		<0.001			0.11			0.38		0.007b		0.15b
P value for interaction	0.13					0.07					0.002
ORR
Rate, %	33.3	42.4	40.6		72.5	50.0		52.6	61.7	68.8	39.7	42.3	57.9	69.4
Odds ratio (95% CI)	1.45 (0.58–3.64)		3.99 (2.40–6.62)			1.11 (0.48–2.59)			1.37 (0.85–2.19)		1.11 (0.61–2.01)b		1.65 (1.16–2.34)b
P value	0.43			<0.001			0.81		0.19		0.73		0.005
P value for interaction	0.06					0.67					0.26

^aInvestigator choice of FOLFIRI/FOLFOX.

^bAdjusted for treatment arm, protocol chemotherapy, prior adjuvant therapy, prior radiotherapy, age, sex, synchronous disease, in place primary, liver metastases.

Bev, bevacizumab; cetux, cetuximab; CI, confidence interval; CT, chemotherapy; FOLFIRI, fluorouracil, leucovorin and irinotecan; FOLFOX, fluorouracil, leucovorin and oxaliplatin; HR, hazard ratio; ORR, objective response rate; OS, overall survival; PFS, progression-free survival.