ve response rate (ORR) 16.4% vs. 4.2%.
With respect to the KRAS status, tumour samples were only available from 23% of the patients (300 of 1298). From the KRAS eva luated population 64% of the patients (192) had KRAS wild-type tumours and 108 patients KRAS mutations. On the basis of this data and since no independent review of imaging data was conducted, results in relation to mutation status are considered non-interpretable.
• EMR 62 202-007: This randomised study in patients with metastatic colorectal cancer after failure of irinotecan-based treatment for metastatic disease as the last treatment before study entry compared the combination of cetuximab and irinotecan (218 patients) with cetuximab monotherapy (111 patients).
The combination of cetuximab with irinotecan compared to cetuximab alone reduced the overall risk of disease progression by 46% and significantly increased objective response rate. In the randomised trial, the improvement in overall survival time did not reach statistical significance; however, in the follow-up treatment, nearly 50% of the patients of the cetuximab alone arm received a combination of cetuximab and irinotecan after progression of disease, which may have influenced overall survival time.
Cetuximab as a single agent
• CA225025: This randomised study in patients with metastatic colorectal cancer who had received prior oxaliplatin-, irinotecan- and fluoropyrimidine-based treatment for metastatic disease compared the addition of cetuximab as a single agent to best supportive care (BSC) (287 patients) with best supportive care (285 patients). The proportion of patients with KRAS wild-type tumours from the patient population eva luable for KRAS status comprised 58%.
The efficacy data generated in this study are summarised in the table below:
|
KRAS wild-type population
|
KRAS mutant population
|
|
Variable/ statistic
|
Cetuximab plus BSC
|
BSC
|
Cetuximab plus BSC
|
BSC
|
|
|
(N=117)
|
(N=113)
|
(N=81)
|
(N=83)
|
|
OS
|
|
|
|
months, median
|
9.5
|
4.8
|
4.5
|
4.6
|
|
(95% CI)
|
(7.7, 10.3)
|
(4.2, 5.5)
|
(3.8, 5.6)
|
(3.6, 5.5)
|
|
Hazard Ratio (95% CI)
|
0.552 (0.408, 0.748)
|
0.990 (0.705, 1.389)
|
|
p-value
|
<0.0001
|
0.9522
|
|
PFS
|
|
|
|
months, median
|
3.7
|
1.9
|
1.8
|
1.8
|
|
(95% CI)
|
(3.1, 5.1)
|
(1.8, 2.0)
|
(1.7, 1.8)
|
(1.7, 1.8)
|
|
|
|
