The purpose of this study is to determine whether CO-1.01 is safe and effective in the treatment of patients with metastatic pancreatic cancer and low hENT1 expression compared with gemcitabine.

Pancreatic cancer is a very serious form of cancer. The majority of patients present with unresectable disease, and the condition is often not diagnosed until the cancer is relatively advanced. The standard first-line treatment for patients with unresectable pancreatic cancer is gemcitabine monotherapy. Unfortunately many of these patients fail to derive benefit from this treatment. No clinical or molecular marker has been established to predict benefit from gemcitabine therapy, so patients are treated empirically until evidence of disease progression or worsening performance status.

The potential for human equilibrative nucleoside transporter-1 (hENT1) expression to predict survival in gemcitabine-treated patients has been studied, and data suggest that patients with low levels of tumor cell hENT1 expression derive less benefit from gemcitabine treatment than patients with high levels of tumor cell hENT1 expression. These data support the hypothesis to be tested in this study that patients with pancreatic tumors expressing low levels of hENT1 will derive minimal benefit from gemcitabine, but will receive benefit from CO-1.01 (gemcitabine elaidate) which enters tumor cells in a hENT1-independent fashion.

Inclusion Criteria:

• Metastatic pancreatic ductal adenocarcinoma (i.e., Stage 4).
• Histological/cytological confirmation of metastatic tissue (not primary tumor) by a central pathology laboratory (H&E stain) to ensure sufficient material is available for later hENT1 analysis.
• Adjuvant chemotherapy/radiotherapy ≥ 6 months prior to randomization.
• Palliative radiotherapy (if administered) ≥ 1 month prior to randomization.
• CT scan ≤30 days prior to randomization
• Performance Status (ECOG) 0 or 1.
• Estimated life expectancy ≥ 12 weeks.
• Age ≥ 18 years.
• Adequate hematological and biological function.
• Written consent on an Institutional Review Board/Institutional Ethics Committee-approved Informed Consent Form prior to any study-specific evaluation.

Exclusion Criteria:

• Prior palliative chemotherapy for pancreatic cancer.
• Radical pancreatic resections (e.g., Whipple procedure) are not allowed < 6 months prior to randomization. Exploratory laparotomy, palliative (e.g., bypass) surgery, or other procedures (e.g., stents) are not allowed < 14 days prior to randomization. In both cases the patient must be sufficiently recovered and stable.
• Symptomatic brain metastases.
• Participation in other investigational drug clinical studies ≤ 30 days prior to randomization.
• Concomitant treatment with prohibited medications.
• History of allergy to gemcitabine or eggs.
• Presence of any serious or unstable concomitant systemic disorder incompatible with the clinical study (e.g., substance abuse, uncontrolled intercurrent illness including active infection, arterial thrombosis, symptomatic pulmonary embolism).
• Any disorder that would hamper protocol compliance.
• Prior nonpancreatic malignancy treated with chemotherapy. Prior malignancies treated with surgery or radiotherapy alone must be in remission ≥ 3 years. The following prior malignancies are allowable irrespective of when they occurred: in situ carcinoma of the cervix, in situ ductal breast cancer, low-grade local bladder cancer, and nonmelanotic skin cancer.
• Females who are pregnant or breastfeeding.
• Refusal to use adequate contraception for fertile patients (females and males during the study and for 6 months after the last study treatment). Adequate forms of contraception are double-barrier methods (condoms or diaphragm with spermicidal jelly or foam); oral, depot, or injectable contraceptives; intrauterine devices; tubal ligation.
• Any other reason the investigator considers the patient should not participate in the study.

The only disclosure restriction on the PI is that the sponsor can review results communications prior to public release and can embargo communications regarding trial results for a period that is more than 60 days but less than or equal to 120 days from the time submitted to the sponsor for review. The sponsor cannot require changes to the communication and cannot extend the embargo.