Gemcitabine + Nab-paclitaxel With LDE-225 (Hedgehog Inhibitor) as Neoadjuvant Therapy for Pancreatic Adenocarcinoma

The investigators propose treating 6-12 patients during the phase 1 portion and 40 patients in the phase 2 stage. Phase 1 Stage: Four cycles of gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m2 on days 1, 8 and 15 in combination with escalating doses (400mg, or 600mg, or 800mg) of LDE-225. After completion of neoadjuvant therapy, the subjects will receive combined chemotherapy and radiation. Then subjects who are eligible for resection will go ahead with surgery. Following resection, subjects will complete two additional cycles of gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m2 in combination with LDE-225. Phase 2 Stage: In the Phase 2 stage the patients will be randomized to receive gemcitabine and nab-paclitaxel with or without the hedgehog inhibitor LDE225: 1. Arm A: Four cycles of gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m on days 1, 8 and 15 in combination with LDE-225 at the recommended phase 2 dose. 2. Arm B: Four cycles of gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m on days 1, 8 and 15. After completion of neoadjuvant therapy, the subjects will receive combined chemotherapy and radiation. Then subjects who are eligible for resection will go ahead with surgery. Following resection, subjects will complete two additional cycles of the pre-surgical therapy. Several correlative laboratory studies will be conducted during the course of this study. They were designed around the goals of providing us with a better understanding of how the stroma-tumor interaction and the intra-tumoral drug levels of gemcitabine are affected with the use of LDE-225. Two additional biopsies are required to participate in this study.