2. Patients who previously received BBI608 for treatment of PDAC on the BBI608-118 (BBI608-201PANC) study may continue with BBI608 in monotherapy between discontinuation of the first chemotherapy backbone and start of the second chemotherapy backbone. Patients may begin chemotherapy backbone on a date determined by the investigator and medical monitor for the sponsor after a minimum of 14 days and a maximum of 30 days since last receiving anti-cancer treatment which included BBI608, provided that all treatment-related adverse events have resolved or have been deemed irreversible (except for alopecia).