High-dose vitamin C: Promising treatment extends survival of pancreatic cancer patients

A study published in the November issue of Redox Biology has found that adding intravenous, high-dose vitamin C to a chemotherapy regimen doubled the survival of patients with late-stage, metastatic pancreatic cancer from eight months to 16 months.

“This is a deadly disease with very poor outcomes for patients. The median survival is eight months with treatment, probably less without treatment, and the five-year survival is tiny. When we started the trial, we thought it would be a success if we got to 12 months survival, but we doubled overall survival to 16 months. The results were so strong in showing the benefit of this therapy for patient survival that we were able to stop the trial early,” explains Joseph J. Cullen, MD, FACS, a professor of Surgery and Radiation Oncology at the University of Iowa, in a statement to StudyFinds.

The study consisted of 34 patients with stage 4 pancreatic cancer who were randomized to two groups. One group received standard chemotherapy (gemcitabine and nab-paclitaxel). The other group received the same chemotherapy plus intravenous infusions of 75 grams of vitamin C three times a week.

The average survival for patients who received chemotherapy and vitamin C was 16 months. Patients who received only chemotherapy survived an average of just eight months.

“Not only does it increase overall survival, but the patients seem to feel better with the treatment. They have fewer side effects, and appear to be able to tolerate more treatment, and we’ve seen that in other trials, too,” Cullen says. 

There is additional evidence of the benefit of intravenous high-dose vitamin C in cancer treatment. Bryan Allen, MD, PhD, a professor and chief of Radiation Oncology at the University of Iowa, and Cullen collaborated on a trial of high dose vitamin C with chemotherapy and radiation for glioblastoma, a deadly brain cancer. These patients also showed a significant increase in survival.

Cullen, Allen, and their colleagues have been conducting research on the anti-cancer effect of high-dose, IV vitamin C for two decades. They demonstrated that IV vitamin C produces high levels in the blood that cannot be achieved by taking vitamin C orally. The high concentration results in changes in cancer cells which makes them more vulnerable to chemotherapy and radiation. Cullen describes the results of their innovation and perseverance as highly encouraging.

“Through every step of the process, it continued to improve. We did it in cells, it worked great. We did it in mice, it worked great. Then our phase one trials looked very promising. So, the progression has just been phenomenal, really,” Cullen tells StudyFinds. “For example, in one of our phase 1 trials for pancreatic cancer, where we combine high-dose IV vitamin C with radiation, we still have three long-term survivors. They’re out nine years at this point, which is far beyond the typical survival range.”

In addition to Cullen and Allen, the UI team also included physicians and researchers from the Departments of Surgery, Radiation Oncology, and Internal Medicine in the UI Carver College of Medicine, as well as the UI College of Public Health and the Medical College of Wisconsin in Milwaukee.