Second TB vaccination boosts immunity in bladder cancer patients and reduces cancer recurrence, pilot study suggests

Two doses of a simple tuberculosis vaccination after surgery helps the immune system fight cancer cells and could greatly improve patient outcomes for the most common type of bladder cancer, according to a pilot study of 40 patients.

Initial results from the RUTIVAC-1 Trial were presented at the European Association of Urology (EAU) Congress in Madrid.

In the randomized controlled trial, administering the vaccine alongside standard treatment led to an elevated immune response, which is known to improve the body’s ability to suppress future tumors. Patients who received the vaccine had no discernible side effects and every patient was cancer-free after five years.

Bladder cancer is the ninth most common cancer in the world, with over 600,000 people diagnosed in 2022. Non-muscle invasive bladder cancer is an early-stage cancer that affects the lining of the bladder and has not progressed into the deeper muscle layer.

Following surgery to remove the tumor, bladder cancer patients are typically given a live Bacillus Calmette Guerin (BCG) inoculation directly into the bladder to help their immune system destroy any remaining cancer cells. While this reduces the chances of their cancer coming back, up to 50% of patients go on to experience disease recurrence or progression.

Principal Investigator, Dr. Cecilia Cabrera, of IrsiCaixa and IGTP, Barcelona, and colleagues tested whether an additional injection of a non-live TB vaccine, called RUTI, would further boost patients’ immune response in a small pilot study.

They found that the RUTI vaccine significantly enhanced the BCG-induced immune response compared with the control group. RUTI vaccination was also associated with significantly higher progression-free survival, with every patient in the RUTI group tumor-free five years later compared with 13 of 18 patients in the control group.

Dr. Cabrera says, “We expected that the RUTI vaccine would improve the immune response for patients, but we didn’t know what effect this might have on cancer progression over five years. It was very surprising for us to see such a vast improvement in cancer progression even with such a small group of patients.”

RUTI vaccination was also well tolerated by patients, with only a mild reaction at the injection site and no systemic adverse effects.

Dr. Cabrera says, “This was a small pilot study, but we’ve been really encouraged by the reduction in disease recurrence and progression in patients treated with the RUTI vaccine.

“We were particularly pleased to see that these results are further supported by an exploratory sub-analysis including only high-grade T1 bladder cancer patients. With such high rates of recurrence in bladder cancer, finding new ways to prevent this is very important.”

RUTI is being developed as a therapeutic vaccine against tuberculosis by Archivel Farma SL. In parallel, RUTI is being developed as an immunotherapeutic agent for bladder cancer as a collaboration between IrsiCaixa, IGTP and Archivel Farma.

Joost Boormans, Professor of Urology at the Erasmus University Medical Center, The Netherlands, and a member of the EAU Scientific Congress Office, said, “This is a well-conducted pilot study and shows promising results.

“With just two injections over and above standard treatment, the burden on patients is very small and I look forward to seeing whether further studies in larger cohorts continue to demonstrate the benefits to patients and improve their outcomes.”

The researchers caution that a larger trial will be needed to confirm the results before the treatment can be considered for wider use.

Two doses of a simple tuberculosis vaccination after surgery helps the immune system fight cancer cells and could greatly improve patient outcomes for the most common type of bladder cancer, according to a pilot study of 40 patients.

Initial results from the RUTIVAC-1 Trial were presented at the European Association of Urology (EAU) Congress in Madrid.

In the randomized controlled trial, administering the vaccine alongside standard treatment led to an elevated immune response, which is known to improve the body’s ability to suppress future tumors. Patients who received the vaccine had no discernible side effects and every patient was cancer-free after five years.

Bladder cancer is the ninth most common cancer in the world, with over 600,000 people diagnosed in 2022. Non-muscle invasive bladder cancer is an early-stage cancer that affects the lining of the bladder and has not progressed into the deeper muscle layer.

Following surgery to remove the tumor, bladder cancer patients are typically given a live Bacillus Calmette Guerin (BCG) inoculation directly into the bladder to help their immune system destroy any remaining cancer cells. While this reduces the chances of their cancer coming back, up to 50% of patients go on to experience disease recurrence or progression.

Principal Investigator, Dr. Cecilia Cabrera, of IrsiCaixa and IGTP, Barcelona, and colleagues tested whether an additional injection of a non-live TB vaccine, called RUTI, would further boost patients’ immune response in a small pilot study.

They found that the RUTI vaccine significantly enhanced the BCG-induced immune response compared with the control group. RUTI vaccination was also associated with significantly higher progression-free survival, with every patient in the RUTI group tumor-free five years later compared with 13 of 18 patients in the control group.

Dr. Cabrera says, “We expected that the RUTI vaccine would improve the immune response for patients, but we didn’t know what effect this might have on cancer progression over five years. It was very surprising for us to see such a vast improvement in cancer progression even with such a small group of patients.”

RUTI vaccination was also well tolerated by patients, with only a mild reaction at the injection site and no systemic adverse effects.

Dr. Cabrera says, “This was a small pilot study, but we’ve been really encouraged by the reduction in disease recurrence and progression in patients treated with the RUTI vaccine.

“We were particularly pleased to see that these results are further supported by an exploratory sub-analysis including only high-grade T1 bladder cancer patients. With such high rates of recurrence in bladder cancer, finding new ways to prevent this is very important.”

RUTI is being developed as a therapeutic vaccine against tuberculosis by Archivel Farma SL. In parallel, RUTI is being developed as an immunotherapeutic agent for bladder cancer as a collaboration between IrsiCaixa, IGTP and Archivel Farma.

Joost Boormans, Professor of Urology at the Erasmus University Medical Center, The Netherlands, and a member of the EAU Scientific Congress Office, said, “This is a well-conducted pilot study and shows promising results.

“With just two injections over and above standard treatment, the burden on patients is very small and I look forward to seeing whether further studies in larger cohorts continue to demonstrate the benefits to patients and improve their outcomes.”

The researchers caution that a larger trial will be needed to confirm the results before the treatment can be considered for wider use.