Panitumumab and irinotecan every 3 weeks is an active and convenient regimen for second-line treatment of patients with wild-type K-RAS metastatic colorectal cancer.
OBJECTIVE
To evaluate the efficacy and safety profile of the combination of panitumumab and irinotecan every 3 weeks in a phase II trial as second-line treatment in patients with advanced wild-type (WT) K-RAS colorectal cancer (CRC).


METHODS
Fifty-three patients received 9 mg/kg of panitumumab followed by 350 mg/m(2) of irinotecan every 21 days until disease progression, unacceptable toxicity or consent withdrawal.


RESULTS
Median age of patients included was 67 years. All patients had previously received 5-fluorouracil, 84 % oxaliplatin and 8 % irinotecan as first-line treatment. Patients received a median of five infusions of panitumumab and irinotecan. On an intention-to-treat analysis, 12 patients (23 %) achieved partial responses and 22 patients (41 %) achieved disease stabilization. Median progression-free survival and overall survival were 4.5 and 15.1 months, respectively. The most frequent treatment-related severe toxicities per patient were diarrhoea (35.8 %), followed by skin rash (32.1 %), asthenia (18.9 %) and neutropenia (13.2 %). A significant association between clinical response and incidence and grade of skin toxicity was observed (p = 0.0032).


CONCLUSIONS
This study shows that the administration of panitumumab plus irinotecan every 3 weeks is safe, active and feasible as second-line treatment in patients with advanced WT K-RAS CRC.
Medical Oncology Department, Ramón y Cajal University Hospital, Ctra. Colmenar Viejo Km. 9,1, 28034, Madrid, Spain. acarrato@telefonica.net
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Carrato
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Gómez
P
P
Escudero
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Chaves
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Rivera
E
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Marcuello
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González
C
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Grávalos
M
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Constenla
J Luis
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Manzano
F
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Losa
J
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Maurel
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Dueñas
B
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Massuti
J
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Gallego
J
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Aparicio
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Antón
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Aranda
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D000970:Antineoplastic Agents / Q000008:administration & dosage; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives*; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D018572:Disease-Free Survival; D004334:Drug Administration Schedule; D005260:Female; D011905:Genes, ras; D006801:Humans; D000077146:Irinotecan; D008297:Male; D008875:Middle Aged; D000077544:Panitumumab; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D018631:ras Proteins / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; D000077544:Panitumumab; D000077146:Irinotecan; D018631:ras Proteins; D002166:Camptothecin