Clinical Trial of High-dose Vitamin C for Advanced Pancreatic Cancer

This is a phase II study. It is designed to provide information about if high-dose ascorbate (vitamin C) increases survival for pancreatic cancer patients. The hypothesis is that vitamin C is well tolerated and increases cancer treatment effectiveness, lengthening survival time for patients with advanced pancreatic cancer.

Adenocarcinoma of the pancreas is the fourth leading cause of cancer death in the United States and is increasing in incidence; the prognosis remains dismal. We propose to investigate an entirely new approach, using pharmacological ascorbate, combined with Gemcitabine, to treat this cancer. Intravenous ascorbate (i.e., ascorbic acid, vitamin C), but not oral ascorbate, produces high plasma concentrations, which are in the range that can be cytotoxic to tumor cells. Though ascorbate has been utilized in cancer therapy, few studies have investigated intravenous deliver of ascorbate. Preliminary studies from our group have demonstrated that ascorbate induces oxidative stress and cytotoxicity in pancreatic cancer cells; this cytotoxicity appears to be greater in tumor vs. normal cells. We hypothesize that production of H2O2 mediates the increased susceptibility of pancreatic cancer cells to ascorbate-induced metabolic oxidative stress. Gemcitabine is the standard chemotherapy drug used to treat pancreatic cancer.