Cetuximab and irinotecan/5-fluorouracil/folinic acid is a safe combination for the first-line treatment of patients with epidermal growth factor receptor expressing metastatic colorectal carcinoma.
BACKGROUND
To investigate the safety/tolerability of the EGFR-antibody cetuximab when added to irinotecan/5-fluorouracil (5-FU)/folinic acid (FA) for first-line treatment in patients with metastatic colorectal cancer (mCRC).


METHODS
Twenty-one patients with untreated, metastatic, EGFR-expressing CRC received cetuximab 400 mg/m(2) as an initial dose, and thereafter 250 mg/m(2) weekly. In addition, patients received infusional 5-FU (24 h) in two dose levels (1500 mg/m(2), low 5-FU group, n = 6 or 2000 mg/m(2), high 5-FU group, n = 15), plus FA at 500 mg/m(2) and irinotecan at 80 mg/m(2), weekly x6 q50d.


RESULTS
Twenty patients were assessable for tolerability after the first cycle. There were no dose limiting toxicities (DLTs) in the low 5-FU group and three DLTs (20%) in the high 5-FU group (two patients with diarrhea grade 3 and one patient with diarrhea grade 4). In the low 5-FU group all six patients received >80% of the planned dose. In the high 5-FU group, seven of 14 patients (50%) received < or =80% of the planned chemotherapy dose during the first cycle due to dosage reductions whilst treatment delays occurred in 10/14 patients. During the whole study period, the common grade 3/4 adverse events were acne-like rash (38%) and diarrhea (29%). Chemotherapy did not affect the pharmacokinetics of cetuximab determined at weeks 1 and 4. Fourteen patients (67%, 95% CI 47% to 87%) had a confirmed response, and six (29%) had stable disease. Median time to progression was 9.9 months [lower 95% confidence limit (CL) 7.9, upper 95% CL not reached]. Median survival time was 33 months (lower CL 20, upper CL not reached). Four patients received secondary surgery with curative intent, and a fifth was potentially eligible for surgery but declined.


CONCLUSIONS
Addition of cetuximab to weekly infusional 5-FU/FA plus irinotecan is safe and first data suggest a promising activity. The 5-FU dose of 1500 mg/m(2) is recommended for further studies.
Folprecht
G
G
University Hospital, Dresden, Germany.
Lutz
M P
MP
Schöffski
P
P
Seufferlein
T
T
Nolting
A
A
Pollert
P
P
Köhne
C-H
CH
D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives; D000068818:Cetuximab; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D018450:Disease Progression; D066246:ErbB Receptors / Q000378:metabolism*; D005472:Fluorouracil / Q000008:administration & dosage; D006801:Humans; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage; D008875:Middle Aged; D009362:Neoplasm Metastasis
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000077146:Irinotecan; D066246:ErbB Receptors; D000068818:Cetuximab; D002955:Leucovorin; D005472:Fluorouracil; D002166:Camptothecin