Gem-TABS in Unresectable Pancreatic Carcinoma

Inclusion Criteria: * Patients must have histologically confirmed pancreatic adenocarcinoma that is metastatic or unresectable. * Patients previously untreated with chemotherapy in the metastatic setting. Prior 5-FU or capecitabine treatment is allowed if: 1) it was given as part of a combined modality chemoradiation regimen in the adjuvant setting and; 2) no greater than 30% of bone marrow was included in the field and; 3) the treatment free interval has been ≥ 6 weeks. * Patients must have measurable disease, defined as at least one lesion that can be measured in at least one dimension (longest diameter to be recorded) as ≥ 20 mm with conventional techniques or as ≥ 10 mm with spiral CT scan. * ECOG performance status ≤2 (Karnofsky ≥60%). * Patients must have normal organ and marrow function as defined below: * leukocytes ≥ 3,000/μl * absolute neutrophil count ≥ 1,500/μl * platelets ≥ 100,000/μl * total bilirubin ≤2.5 X institutional upper limit of normal * AST(SGOT)/ALT(SGPT) ≤2.5 X institutional upper limit of normal - or - * AST(SGOT)/ALT(SGPT) ≤5 X institutional upper limit of normal in patients with liver metastasis * creatinine ≤1.5 X institutional upper limit of normal and creatinine clearance \> 30 ml/min (Cockcroft-Gault method) * Has a negative serum or urine pregnancy test within 7 days prior to initiation of therapy (female patients of childbearing potential). Postmenopausal women must have been amenorrheic for at least 12 months to be considered of non-childbearing potential. Patients will agree to continue contraception for 30 days from the date of the last study drug administration. * Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: * Patients who have had prior chemotherapy for pancreatic adenocarcinoma in the metastatic setting * Patients who have received chemoradiation within the last 6 weeks prior to registration * Patients with known allergy or severe reactions to gemcitabine * Patients with uncontrolled hypertension and history of uncontrolled congestive heart failure * Patients may not be receiving any other investigational agents or received investigational agents within the 28 days prior to registration. * Patients with known brain metastases are excluded. * Patients with active (not in remission) malignancies other than pancreatic cancer * Pregnant women are excluded from this study because gemcitabine is a Class D agent with the potential for teratogenic or abortifacient effects. * Patients with immune deficiency are at increased risk of lethal infections when treated with marrow-suppressive therapy. Therefore, HIV-positive patients receiving combination antiretroviral therapy are excluded from the study. * Patients who require ongoing (chronic) treatment with medications, the absorption of which may be altered by NaHCO3 (benzodiazepines, flecainide, ketoconazole, lithium, iron salts, methenamine, methotrexate, quinidine, sulfa-containing antibiotics, and tetracycline), and cannot be switched to alternate medications are excluded. * Patients who routinely use antacids including sodium bicarbonate, aluminum hydroxide, and calcium carbonate are excluded. * Patients with a documented history of severe\* COPD are excluded. \*defined as GOLD stage III or greater. For patients with a documented history of COPD, pulmonary function tests to establish GOLD stage must be documented within 6 weeks prior to start of protocol therapy.