The San Antonio Medical Foundation (SAMF) has awarded Texas Biomedical Research Institute Professor Jordi B. Torrelles, Ph.D., with a $173,000 grant to study a modified Mycobacterium bovis Bacillus Calmette et Guérin (BCG) vaccine shown to have promise for treating bladder cancer. BCG is a weakened strain of Mycobacterium bovis, a vaccine for tuberculosis. BCG is the main intravesical immunotherapy for early stage bladder cancer, meaning the drug is directly injected into the bladder. BCG immunotherapy is used to prompt the immune system into attacking cancer cells.
About 2.3% of the world population (170 million people) will be diagnosed with bladder cancer at some point during their lifetime, making this disease a major global public health issue. Bladder cancer occurs predominantly in elderly men. The American Cancer Society estimates there will be 80,470 new cases of bladder cancer in the U.S. in 2019 and 17,670 deaths from the disease.
For early stages of bladder cancer, the current standard therapy is surgical removal followed by several treatments with the live bacteria tuberculosis vaccine, BCG. BCG therapy is ineffective in approximately 30-40% of cases and disease recurs in up to 50% of patients. For later stages of bladder cancer, treatment involves complete removal of the bladder.
“Our goal is to dramatically improve treatment for bladder cancer by injection of a modified BCG vaccine into bladder cancer tumors in affected patients,” explained Torrelles, Professor and Lead of Texas Biomed’s Population Health program. “Through our work in developing a more efficacious tuberculosis vaccine, we have developed a biochemical procedure that removes toxic fats from the cell surface of BCG creating what we call dBCG. Our current results show that dBCG is much safer to administer to mucosal sites like the lung and the bladder and has significantly improved efficacy.”
Based on an innovative concept and current data, Dr. Torrelles and Robert Svatek, M.D. at UT Health San Antonio are principal investigators together on this project. They anticipate that direct injection of dBCG into bladder cancer tumors will reduce recurrence and progression of cancer. They are hopeful this approach will enable therapy for bladder cancer that does not involve removal of the bladder. Dr. Torrelles predicts this will be game-changing for those who suffer from bladder cancer.
At Texas Biomed, Dr. Torrelles will be responsible for the production of the modified BCG vaccine to be tested in bladder cancer mouse models by Dr. Svatek. Dr. Torrelles, Varsin Archer, M.S., and Hong Dixon, Ph.D., at Southwest Research Institute, will supervise and be involved in the analytical quality controls for the production of the modified BCG for the mouse studies conducted by Dr. Svatek.
Russell Ault with Texas Biomed and Juan I. Moliva, Ph.D. with the National Institutes of Health are also involved in this study.