Phase I/II Study to Evaluate Nab-paclitaxel in Substitution of CPT11 or Oxaliplatin in FOLFIRINOX Schedule as First Line Treatment in Metastatic Pancreatic Cancer

Inclusion Criteria:

* . Males or females ≥ 18 years old and ≤ 75 years old;
* Histological or cytological evidence of a diagnosis of pancreatic ductal adenocarcinoma;
* Written informed consent prior to any study-specific procedures; 4. Measurable metastatic disease, defined in according to RECIST Version 1.1 (Eisenhower et al. 2009), that had not previously been treated with CT for metastatic disease;
* Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1 ;
* Absence of previous abdominal radiotherapy on target lesions (except radiation therapy analgesic if it has not been performed on measurable targets);
* Absence of heart failure or angina or infarction within 12 months previous inclusion;
* Have adequate organ function including:

Hematologic: absolute neutrophil count (ANC) ≥ 1.5 x 109/L, platelets ≥ 100 x 109/L.

Hepatic: Bilirubin ≤ 1.5 times upper limits of normal (ULN) (Pts may have endoscopic or radiologic stenting to treat biliary obstructions).

Renal: Serum creatinine within normal limits ≤1.5 times ULN.

Exclusion Criteria:

* Age of 76 years or older;
* Endocrine or acinar pancreatic carcinoma;
* Previous radiotherapy for measurable lesions;
* Central nervous system metastasis;
* Other concomitant cancer or history of cancer outside a carcinoma in situ of the cervix or basal or squamous cell of the skin;
* Pts already included in another clinical trial with other experimental drugs;
* Current active infection;
* Have serious pre-existing medical conditions or serious concomitant systemic disorders that would compromise the safety of the patient or his/her ability to complete the study, at the discretion of the investigator (for example, unstable angina pectoris, or a clinically significant history of cardiac disease or uncontrolled diabetes mellitus);
* Females who are pregnant or lactating;
* Unable to undergo medical test for geographical, social or psychological reason
* Known dihydropyrimidine dehydrogenase (DPD) deficiency