Inclusion Criteria:

Subjects should meet all of the following criteria to participate in
the trial.

- Histologically confirmed colorectal or gastric cancer patients who are chemonaive or
failed to 1st line chemotherapy

- Subjects who are expected to receive toxicity test at least once after FOLFIRI
treatment.

- Aged 18 years or older.

- ECOG performance status of ≤ 2.

- Anticipated life expectancy of ≥ 3 months.

- Clinically acceptable function of bone marrow, kidney and liver function as below.

1. ANC ≥ 1500/mm3 and platelet count ≥ 100,000/mm3

2. Serum total bilirubin ≤ 1.5 x ULN, alkaline phosphatase ≤ 2.5 x ULN, Serum ALT
and AST ≤ 2.5 x ULN (Serum ALT and AST ≤ 5 x ULN, if liver metastases are
present)

3. Serum creatinine ≤ 1.5 mg/dL or CLcr > 60 ml/min

- Subjects whose written informed consent can be obtained prior to their participation
in the trial.

Exclusion Criteria: Subjects who meet any of the following criteria should not be included
in the trial.

- Pregnant or breast feeding women

- Serious concurrent complication, severe active infection.

- Subjects with chronic diarrhea, paralytic ileums, pulmonary fibrosis or pneumonia
interstitialis

- Subjects with epilepsia or severe psychiatric disorders.

- Subjects who are regarded to be unsuitable for this trial by the investigator.

- Subjects who are participating in other clinical trials

- Subjects who have received prior chemotherapy including irinotecan.