title: Panitumumab: a review of its use in metastatic colorectal cancer.
abstract: Panitumumab (Vectibix(R)) is a recombinant, fully human, IgG2 anti-epidermal growth factor receptor (EGFR) monoclonal antibody. This article reviews the clinical efficacy of intravenous panitumumab in combination with chemotherapy in the first- and second-line treatment of metastatic colorectal cancer and as monotherapy in chemotherapy-refractory metastatic colorectal cancer, as well as summarizing its pharmacological properties and tolerability. Panitumumab is indicated for use in patients with wild-type rather than mutant KRAS tumours. The efficacy of intravenous panitumumab 6 mg/kg administered every 2 weeks was examined in randomized, open-label, multicentre, phase III trials in patients with metastatic colorectal cancer. When administered as first- or second-line treatment in combination with chemotherapy, panitumumab plus chemotherapy prolonged progression-free survival to a significantly greater extent than chemotherapy alone in patients with wild-type KRAS tumours; no significant between-group difference in overall survival was seen in the second-line treatment trial. In patients with mutant KRAS tumours, progression-free survival was significantly shorter with panitumumab plus oxaliplatin-based chemotherapy than with oxaliplatin-based chemotherapy alone in the first-line treatment trial, with no significant difference between patients receiving panitumumab plus irinotecan-based chemotherapy (FOLFIRI) and those receiving FOLFIRI alone in the second-line treatment trial. In chemotherapy-refractory patients with metastatic colorectal cancer, panitumumab monotherapy plus best supportive care prolonged progression-free survival to a significantly greater extent than best supportive care alone in both the overall population and in patients with wild-type KRAS tumours, but not in those with mutant KRAS tumours; there was no significant between-group difference in overall survival. Panitumumab has an acceptable tolerability profile when administered as monotherapy or in combination with chemotherapy. It is associated with the skin-related toxicities characteristic of EGFR inhibitors and appears to have a low risk of immunogenicity. In conclusion, in patients with wild-type KRAS tumours, panitumumab is a useful option in combination with chemotherapy for the first- and second-line treatment of metastatic colorectal cancer or as monotherapy for the treatment of chemotherapy-refractory metastatic colorectal cancer.
authors.affiliation: Adis, a Wolters Kluwer Business, Auckland, New Zealand. demail@adis.co.nz
authors.forename: Gillian M
authors.initials: GM
authors.lastname: Keating
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects* / Q000493:pharmacokinetics / Q000627:therapeutic use*; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000493:pharmacokinetics / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols; D017326:Clinical Trials, Phase III as Topic; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000401:mortality / Q000473:pathology; D018572:Disease-Free Survival; D066246:ErbB Receptors / Q000037:antagonists & inhibitors; D005260:Female; D011905:Genes, ras; D006801:Humans; D008297:Male; D051379:Mice; D009362:Neoplasm Metastasis; D000077544:Panitumumab; D016032:Randomized Controlled Trials as Topic
chemical_list: D000911:Antibodies, Monoclonal; D000970:Antineoplastic Agents; D000077544:Panitumumab; D066246:ErbB Receptors