A Study of Xeloda (Capecitabine) in Combination With Oxaliplatin in Patients With Metastatic Colorectal Cancer.

A Study of Xeloda (Capecitabine) in Combination With Oxaliplatin in Patients With Metastatic Colorectal Cancer.

An Open-label Study to Assess the Pharmacokinetic Interaction Between Xeloda and Oxaliplatin in Patients With Metastatic Colorectal Cancer.

This single arm study will investigate possible pharmacokinetic interactions between Xeloda and oxaliplatin, and assess whether the pharmacokinetics of Xeloda and/or oxaliplatin is influenced by the addition of Avastin. All subjects will provide samples for pharmacokinetic analysis during the first 3 cycles of treatment. In cycles 1 and 2 patients will receive a treatment regimen containing Xeloda (1000mg/m2 bid) and oxaliplatin (130mg/m2 iv) and in cycle 3 Avastin (7.5mg/kg iv) will be added to the regimen. The anticipated time on study treatment is 3-12 months, and the target sample size is <100 individuals.

Area Under The Plasma Concentration-Time Curve From Zero To Infinity (AUC0-Inf) of 5'-Deoxy-5-fluorouridine 5'-(DFUR)

AUC0-infinity represents the area under the concentration-time curve of the analyte (5'-DFUR) in plasma over the time interval from 0 extrapolated to infinity. The analyte 5'-DFUR, the direct precursor of 5-fluorouracil (5-FU), is considered to be the most important metabolite of capecitabine in plasma. The unit of measure was nanograms per millilitre per hour (ng/mL * hr).

AUC0-infinity represents the area under the concentration-time curve of the analyte (free platinum) in plasma over the time interval from 0 extrapolated to infinity. AUC0-inf for free platinum was calculated for each participant from the concentration-data obtained on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3. Free platinum is not bound to plasma proteins and is considered to be the most clinically significant measure of pharmacological and toxicological activity.

Predose , 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the 2 hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3.

AUC0-infinity represents the area under the concentration-time curve of the analytes (5'-DFCR, 5-FU, and FBAL) in plasma over the time interval from 0 extrapolated to infinity. After oral administration, capecitabine is first metabolized in the liver to 5'-deoxy-5-fluorocytidine (5'-DFCR), which is then converted to 5'-DFUR, and then catalytically activated to 5-FU.

Area under the plasma concentration-time curve from time zero to the time of the last measurable plasma concentration time point of capecitabine and its metabolites (5'-DFUR, 5'-DFCR, 5 FU, and FBAL).

Maximum Plasma Concentration (Cmax) of Capecitabine and Its Metabolites (5'-DFUR, 5'-DFCR, 5 FU, and FBAL)

Cmax is defined as maximum observed analyte concentration of capecitabine and its metabolites (5'-DFUR, 5'-DFCR, 5 FU, and FBAL)

Elimination Half-life Period (t1/2 Beta) of Capecitabine and Its Metabolites (5'-DFUR , 5'-DFCR, 5 FU, and FBAL)

t1/2 Beta is the time measured for the plasma concentration to decrease by 1 half to its original concentration of capecitabine and its metabolites (5'-DFUR , 5'-DFCR, 5 FU, and FBAL)

AUC0-infinity represents the area under the concentration-time curve of the analyte (total platinum) in plasma over the time interval from 0 extrapolated to infinity.

Pre-dose, and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the two hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3

Area under the plasma concentration-time curve from time zero to the time of the last measurable plasma concentration time point of Total And Free Platinum.

pre-dose, and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the two hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3.

Pre-dose, and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the two hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3.

T1/2 beta is the time measured for the plasma concentration to decrease by 1 half to its original concentration of total and free platinum.

Pre-dose, and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the two hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3

VSS is defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired blood concentration of a drug. Steady state volume of distribution (Vss) is the apparent volume of distribution at steady-state.

CL is a calculation of the rate at which a drug is removed from the body via renal, hepatic and other clearance pathways, expressed as volume (milliliters) per unit of time (hour).

Pre-dose, and 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48 and 72 hours from the beginning of the two hour oxaliplatin infusion on Days 2 to 5 of Cycle 1, and Days 1 to 4 for Cycle 2 and 3

An adverse event is defined as any untoward medical occurrence in a participant or clinical investigation participant administered a pharmaceutical product. This includes any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. Pre-existing conditions which worsened during the study were also to be reported as AEs.

Number of participants with marked laboratory abnormalities (hematology, coagulation, liver function, renal function, protein, electrolytes, miscellaneous).

Inclusion Criteria: adult patients, >=18 years of age; adenocarcinoma of colon or rectum, with metastatic or locally advanced disease. Exclusion Criteria: previous systemic treatment for advanced or metastatic disease; previous treatment with oxaliplatin or Avastin.