Background: : The multinational MABEL study of 1147 patients with metastatic colorectal cancer (mCRC) who had recently failed an irinotecan-containing regimen confirmed in a community practice setting the efficacy and safety of cetuximab combined with irinotecan.
Methods: : This report describes a post hoc analysis of the influence of prophylactic premedication on the incidence of infusion-related reactions (IRRs) in the MABEL study. The analysis was focused on the subpopulation of patients premedicated with antihistamines either with (n = 700) or without (n = 422) corticosteroids. Stepwise Cox regression modeling was used to examine the explanatory value of the type of premedication on progression-free survival (PFS) and overall survival (OS) times.
Results: : The incidence of IRRs was lower in the group of patients who received antihistamine plus corticosteroid (9.6%) compared with those who received antihistamine alone (25.6%). A similar trend was seen for grade 3 or 4 IRRs (1.0% vs 4.7%, respectively). The 12-week PFS rates (61% vs 60%), median PFS (16.1 vs 13.1 weeks) and OS (9.2 vs 9.0 months) times for patients who received, respectively, antihistamines with and without corticosteroids were similar. Cox regression modeling did not identify any impact of type of premedication used (antihistamine with or without corticosteroids) on the efficacy of treatment in relation to PFS or OS.
Conclusions: : Prophylactically premedicating mCRC patients with both antihistamine and a corticosteroid appeared to reduce the frequency of cetuximab-associated IRRs. Given that this was a post hoc analysis, caution must be exercised in the interpretation of these data, which require formal confirmation in a randomized study. Cancer 2010. (c) 2010 American Cancer Society.