Part 1

Inclusion Criteria:

- Histologically or cytologically confirmed solid tumour refractory to standard therapy
or for whom no established therapy exists

- Age >= 18 years

- Karnofsky performance status of >= 70%

- Life expectancy of >= 3 months

- Absolute neutrophil count of >= 1.5 × 109/l, platelet count of ³ 100 × 109/l,
haemoglobin level of ³ 10 g/dl (>= 6.2 mmol/l) (prior transfusion is permitted)

- Normal hepatic and renal function as defined by serum bilirubin £ 1.5 times the upper
limit of normal, ALT and AST £ 2.5 times the upper limit of normal (£ 5 times the
upper limit of normal in the presence of hepatic metastases), creatinine clearance ³
50 ml/min (by Cockroft-Gault formula)

- Male and female patients

- Written informed consent to participate in the study

Part 1 Exclusion Criteria:

- More than two previous courses of documented myelosuppresive chemotherapy (epidermal
growth factor targeted therapy does not constitute a course of chemotherapy)

- CNS metastases (a CT or MRI scan should be done if there is a clinical suspicion of
CNS metastases)

- Major surgery, chemotherapy or radiation therapy (except palliative) within 4 weeks
of treatment start

- Previous investigational cytotoxic treatment for malignant disease within 30 days
before the start of the study

- Any treatment with non-oncological investigational drugs within 30 days before the
start of the study

- Pregnancy or breast feeding (all women of childbearing potential must have a
pregnancy test before inclusion in the study; post-menopausal women must be
amenorrhoeic for at least 12 months). Female patients must use adequate contraceptive
protection.

- Fertile males not willing to use contraception or whose female partners are not using
adequate contraceptive protection

- Uncontrolled infections

- Clinically significant cardiac impairment or unstable ischaemic heart disease
including a myocardial infarction within three months of study entry

- History of alcoholism, drug addiction, or any psychiatric or psychological condition
which in the opinion of the investigator would impair study compliance

- History of hypersensitivity to sulphonamides

- Prior severe or unexpected reaction to fluoropyrimidine therapy (which may be
explained by dihydropyrimidine dehydrogenase deficiency or hypersensitivity to 5-FU)

- Malabsorption syndrome or other condition which may affect absorption of drug

- Concurrent or previous malignancy of a different tumour type within five years of
starting the study except for adequately treated non-melanoma skin cancer or cervical
intraepithelial neoplasia

- Treatment within two weeks before the start of the study with any of the following:
coumarin anti-coagulants, terfenadine, cisapride, cyclosporin, tacrolimus,
theophylline, diazepam, sulphonylurea hypoglycaemics, phenytoin, or carbamazepine

- Legal incapacity

Part 2

Inclusion Criteria:

- Ambulant patients with progressive metastatic CRC who have received prior treatment
with 5 FU and irinotecan and/or oxaliplatin either as single agents or in
combination. Either 5 FU and/or irinotecan and/or oxaliplatin may have been
administered in the adjuvant setting or for the treatment of metastatic disease.
Patients who have received both 5-FU and irinotecan or oxaliplatin in the adjuvant
setting only must have experienced disease recurrence within one year of starting
chemotherapy.

- At least one unidimensionally measurable lesion according to the RECIST criteria

- Age ³ 18 years

- Karnofsky performance status of ³ 70%

- Life expectancy of ³ 3 months

- Absolute neutrophil count of ³ 1.5 × 109/l, platelet count of ³ 100 × 109/l,
haemoglobin level of ³ 10 g/dl (³ 6.2 mmol/l) (prior transfusion is permitted)

- Normal hepatic and renal function as defined by serum bilirubin £ 1.5 times the upper
limit of normal, ALT and AST £ 2.5 times the upper limit of normal (£ 5 times the
upper limit of normal in the presence of hepatic metastases), creatinine clearance ³
50 ml/min (by Cockroft-Gault formula)

- Male and female patients

- Written informed consent to participate in the study

Part 2 Exclusion Criteria:

- Prior chemotherapy other than 5-FU, irinotecan and/or oxaliplatin

- CNS metastases (a CT or MRI scan should be done if there is a clinical suspicion of
CNS metastases)

- Major surgery, chemotherapy or radiation therapy (except palliative) within 4 weeks
of treatment start

- Previous investigational cytotoxic treatment for malignant disease within 30 days
before the start of the study

- Any treatment with non-oncological investigational drugs within 30 days before the
start of the study

- Pregnancy or breast feeding (all women of childbearing potential must have a negative
pregnancy test before inclusion in the study; post-menopausal women must be
amenorrhoeic for at least 12 months). Female patients must use adequate contraceptive
protection.

- Fertile males not willing to use contraception or whose female partners are not using
adequate contraceptive protection

- Uncontrolled infections

- Clinically significant cardiac impairment or unstable ischaemic heart disease
including a myocardial infarction within three months of study start

- History of alcoholism, drug addiction, or any psychiatric or psychological condition
which in the opinion of the investigator would impair study compliance

- History of hypersensitivity to sulphonamides

- Prior severe or unexpected reaction to fluoropyrimidine therapy (which may be
explained by dihydropyrimidine dehydrogenase deficiency or hypersensitivity to 5-FU)

- Malabsorption syndrome or other condition which may affect absorption of drug

- Concurrent or previous malignancy of a different tumour type within five years of
starting the study except for adequately treated non-melanoma skin cancer or cervical
intraepithelial neoplasia

- Treatment within two weeks before the start of the study with any of the following:
coumarin anti-coagulants, terfenadine, cisapride, cyclosporin, tacrolimus,
theophylline, diazepam, sulphonylurea hypoglycaemics, phenytoin, or carbamazepine

- Legal incapacity