Safety and Pharmacokinetics of Recombinant Anti-EGFr Antibody in Patients With Metastatic Colorectal Cancer

Two dose levels were tested: Recombinant Anti-EGFr Antibody Low-dose level patients received initial dose 100 mg/m2 and 4 weeks later 250 mg/m2 weekly maintenance to the disease progression or unacceptable toxicity or death or withdraw informed consent.High-dose level patients received cetuximab initial dose 400 mg/m2 and 4 weeks later loading 400 mg/m2 and 250 mg/m2 weekly maintenance to the disease progression or unacceptable toxicity or death or withdraw informed consent. Dose limiting toxicity (DLT) was defined as: grade 4 or 3-time grade 3 cutaneous toxicity,successive 3-time infusion suspension due to grade 3 cutaneous toxicity,any other ≥grade 3 adverse reaction or acute pneumonia, interstitial pneumonia, and other lung diseases. Cohorts of 3 patients receive single dose of low-dose group of Recombinant Anti-EGFr Antibody. If the ratio of the dose limiting toxicity (DLT) after a single dose is not more than a third, then high-dose group can be treated.After high-dose(initial dose 400 mg/m2, iv., 2 h),safety will be observed and blood sampling will be taken for a single dose pharmacokinetic analysis.After 4-week continuous administration (loading dose 400 mg/m2, iv., 2 h; maintenance dose 250 mg/m2, iv, 1 h, q1w) until disease progression, unacceptable toxicity reaction, death or revocation of informed consent.As the blood concentration reach steady state, blood sampling will be collected for steady-state pharmacokinetic analysis, for 1 week.After completion of the steady-state pharmacokinetics,patients can receive chemotherapy,and safety (including immunogenicity) and curative effect will be observed.