8. For male or female patient of child producing potential: Must agree to use contraception or take measures to avoid pregnancy during the study and for 180 days for female and male patients, of the final FOLFIRI dose. Patients who receive single agent napabucasin without FOLFIRI must agree to use contraception or take measures to avoid pregnancy during the study and for 30 days for female patients and 90 days for male patients, of the final napabucasin dose.