Valproic Acid/Simvastatin Plus Gemcitabine/Nab-paclitaxel Based Regimens in Untreated Metastatic Pancreatic Adenocarcinoma Patients

Inclusion Criteria: Written informed consent to study procedures and to correlative studies. Histologically or cytologically proven metastatic PDAC. No prior treatments (chemotherapy, radiation or surgery) for PDAC Either sex aged ≥ 18 years. Eastern Cooperative Oncology Group (ECOG) Performance Status ≤1 at study entry. Imaging-documented measurable disease, according to RECIST 1.1 criteria. Known dihydropyrimidine dehydrogenase (DPD) activity is mandatory for patients enrolled in PAXG scheme. Adequate bone marrow haematological function: absolute neutrophil count (ANC) ≥ 1.5 x 109/L AND platelet count ≥ 100 x 109/L AND haemoglobin ≥ 9 g/dL. Adequate liver function: total bilirubin ≤ 1.5 x upper limit of normal (ULN) or ≤ 2 in case of biliary stent) and aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ≤ 5 X ULN. Adequate renal function: serum creatinine ≤ 1.5 mg/dL OR creatinine clearance ≥ 60 mL/min in males and ≥50 mL/min in females (calculated according to Cockroft-Gault formula). Exclusion Criteria: Prior malignancy within one year. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin that has undergone potentially curative therapy or in situ cervical cancer. Prior chemotherapy or any other medical treatment for metastatic PDAC (previous adjuvant chemotherapy is allowed if terminated > 6 months previously). Patients who have had prior treatment with an HDAC inhibitor and patients who have received compounds with HDAC inhibitor-like activity, such as valproic acid. Current use of statins or fibrates or any medication for hypercholesterolemia for any time during the 3 months before the study. Proven hypersensitivity to statins. Major surgical intervention within 4 weeks prior to enrollment; Pregnancy and breast-feeding. Brain metastasis. Evidence of severe or uncontrolled systemic disease or any concurrent condition which in the investigator's opinion makes it undesirable for the patient to participate in the study, or which would jeopardize compliance with the protocol, or would interfere with the results of the study. Patients with long QT-syndrome or QTc interval duration > 480 msec or concomitant medication with drugs prolonging QTc (see list in the appendix). History of poor co-operation, non-compliance with medical treatment, unreliability or any condition that may impair the patient's understanding of the Informed consent form. Participation in any interventional drug or medical device study within 30 days prior to treatment start. Patients who cannot take oral medication, who require intravenous alimentation, have had prior surgical procedures affecting absorption, or have active peptic ulcer disease. Sexually active males and females (of childbearing potential) unwilling to practice contraception (barrier contraceptive measure or oral contraception) during the study and until 6 months after the last trial treatment.