New Study Aims to Improve Bladder Cancer Treatment with High-Dose Intravenous Vitamin C

Researchers at The University of Kansas Cancer Center have secured a $3.6 million grant from the U.S. Department of Defense to study high-dose intravenous Vitamin C for treating muscle-invasive bladder cancer. This type of cancer, affecting 25% of bladder cancer patients, occurs when cancer cells spread to the muscle layer of the bladder wall.

Cisplatin-based chemotherapy before surgery is the standard treatment for most bladder cancer types. However, more than half of patients with muscle-invasive bladder cancer cannot receive this treatment due to underlying health issues. To address this treatment gap, researchers are launching a Phase II clinical trial that explores an innovative combination therapy: high-dose intravenous Vitamin C alongside the chemotherapies gemcitabine and carboplatin. Results from their phase I trial showed that this combination shrunk tumor size in up to one-third of patients before surgery. In addition, this therapy was well-tolerated, with few side effects, and patients maintained their quality of life throughout the treatment.

John Taylor, III, MD, MS, professor in the department of Urologic Surgery and Cancer Biology and co-leader of the cancer center’s Drug Discovery, Delivery and Experimental Therapeutics research program, is leading the multi-site study.

“Intravenous Vitamin C achieves significantly higher levels in the blood than oral intake,” Dr. Taylor explained. “Administering it intravenously allows us to reach supratherapeutic levels, where Vitamin C can be toxic to cancer cells.”

Bladder cancer is one of the costliest cancers to treat over a patient’s lifetime. In 2020, the cost of treating bladder cancer in the United States was nearly $6 billion.

“Vitamin C is a comparatively low-cost and readily available therapy,” Dr. Taylor said. “For people who are ineligible for the standard chemotherapy regimen, this new approach has the potential to be practice changing.”

Collaborative effort

The phase I study was conducted at KU Cancer Center. The phase II study will be conducted at both KU Cancer Center and the University of Iowa Holden Comprehensive Cancer Center.

“Researchers at The University of Iowa Holden Comprehensive Cancer Center are established experts on Vitamin C, making them the perfect partner as we move into phase II of the trial,” Dr. Taylor said. “This is a truly collaborative effort that is only possible at major academic medical centers like ours.”

Participant recruitment is expected to start by the end of 2024.

Disclaimer

The work was supported by the Assistant Secretary of Defense for Health Affairs endorsed by the Department of Defense, in the amount of $3,560,880, through the Peer Reviewed Cancer Research Program under Award No. (CA230241, Award No. HT9425-24-1-0797). Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the Assistant Secretary of Defense for Health Affairs or the Department of Defense.