A Study of Nab-Paclitaxel and Gemcitabine With or Without Olaratumab (LY3012207) in Participants With Metastatic Pancreatic Cancer

Inclusion Criteria:

* Histological or cytological diagnosis of adenocarcinoma of the exocrine pancreas that is metastatic (Stage IV) and not amenable to resection with curative intent.
* If present, clinically significant or symptomatic amounts of ascites should be drained prior to Day 1.
* Have had no prior systemic treatment for metastatic disease. Prior adjuvant or neo-adjuvant chemotherapy or radiochemotherapy (other than nab-paclitaxel) is allowed if completed ≥3 months prior to enrollment and no lingering toxicities are present.
* Prior radiation therapy for treatment of cancer is allowed to \<25% of the bone marrow.
* Phase 2: archival tumor tissue or be willing to provide a pre-treatment biopsy.
* Measurable or nonmeasurable but evaluable disease as defined by the Response Evaluation Criteria in Solid Tumors (RECIST 1.1).
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1.
* Discontinued all previous treatments for cancer ≥4 weeks prior.
* Adequate organ function.
* Life expectancy of at least 3 months.

Exclusion Criteria:

* Serious concomitant systemic disorder.
* Have received first line treatment for metastatic pancreatic cancer.
* Received prior treatment with nab-paclitaxel.
* Have known central nervous system malignancy or metastasis.
* Current hematologic malignancies.
* Participated within the last 30 days in a clinical trial involving an investigational product.
* Women with a positive pregnancy test or lactating.
* Have endocrine pancreatic tumors or ampullary cancer.
* Currently enrolled in another clinical trial.
* Have a known additional malignancy that is progressing or required active treatment within the past 1 year.
* Known allergy to nab-paclitaxel or gemcitabine or any ingredient of study drug formulations.
* Are taking certain anti-coagulant medications such as warfarin and are unable to be switched to other similar medicines.