Inclusion Criteria:

• Written informed consent (patient's written understanding of and agreement to participate in this study).
• Patients with confirmed extensive small cell lung cancer (SCLC).
• No prior chemotherapy within 5 years of the diagnosis of SCLC.
• Presence of either measurable or non-measurable SCLC by X-ray or physical examination.
• At least 3 weeks since last major surgery (a lesser period is acceptable if decided to be in the best interest of the patient).
• At least 24 hours since prior radiotherapy. Patients who have received radiotherapy must have recovered from any reversible side effects, such as nausea and vomiting.
• Laboratory criteria: Patients must have adequate bone marrow reserve and adequate kidney and liver function.

Exclusion Criteria:

• Symptoms of spreading of the disease to the brain that requires treatment with drugs called steroids.
• Any active infection.
• Severe medical problems other than the diagnosis of SCLC, that would limit the ability of the patient to follow study guidelines or that would expose the patient to extreme risk.
• Ongoing or planned chemotherapy, immunotherapy, radiotherapy, or investigational therapy for the treatment of SCLC.
• Use of an investigational drug within 30 days before the first dose of study medication.
• Women who are pregnant or lactating.
• Patients of child-bearing potential who refuse to practice an adequate form of birth control.
• Patients with clinical evidence of any stomach or intestinal (GI) condition.
• Patients requiring treatment with the drug cyclosporin A.