Table of Contents
- What is BACILLUS CALMETTE-GUÉRIN (BCG), TICE?
- How Does BCG Work?
- Medical Conditions Treated
- How is BCG Administered?
- Current Clinical Trials
- Efficacy of BCG Treatment
- Potential Side Effects
- Important Considerations for Patients
What is BACILLUS CALMETTE-GUÉRIN (BCG), TICE?
BACILLUS CALMETTE-GUÉRIN (BCG), TICE is a type of immunotherapy used primarily in the treatment of non-muscle invasive bladder cancer (NMIBC). It is a live attenuated strain of Mycobacterium bovis, originally developed as a vaccine against tuberculosis. In the context of bladder cancer treatment, BCG is used to stimulate the immune system to fight cancer cells.[1]
BCG is also known by other names, including TICE BCG and BCG (BACILLUS CALMETTE-GUÉRIN), LIVE ATTENUATED STRAIN TICE. It is available as a powder for intravesical suspension, which means it is prepared as a liquid to be instilled directly into the bladder.[2]
How Does BCG Work?
When BCG is introduced into the bladder, it triggers an immune response. The body’s immune system recognizes the BCG bacteria as foreign and launches an attack. This immune activation not only targets the BCG bacteria but also the cancer cells in the bladder. The exact mechanism is not fully understood, but it is believed that BCG causes the body to produce certain proteins and activate immune cells that can recognize and destroy cancer cells.[1]
Medical Conditions Treated
BCG is primarily used to treat high-risk non-muscle invasive bladder cancer (HR NMIBC). This includes:[1]
- T1 tumors (tumors that have grown into the connective tissue layer beneath the bladder lining)
- High-grade/G3 tumors (fast-growing, aggressive tumors)
- Carcinoma in situ (CIS) – a flat, high-grade cancer confined to the bladder lining
- Multiple, recurrent, and large (≥3cm diameter) tumors
BCG is used both as an initial treatment for newly diagnosed NMIBC and as a treatment for NMIBC that has persisted or recurred following initial BCG therapy.[1]
How is BCG Administered?
BCG is administered through a procedure called intravesical instillation. This means the medication is delivered directly into the bladder through a catheter. The typical treatment schedule includes:[2]
- Induction therapy: Weekly treatments for 6 weeks
- Maintenance therapy: Three weekly treatments at 3, 6, 12, 18, and 24 months after initial treatment
The dose is typically one vial of TICE BCG or an equivalent dose of another approved BCG strain. For patients with persistent disease, a re-induction course may be given.[2]
Current Clinical Trials
BCG is currently being studied in several clinical trials to further improve its efficacy and explore new treatment combinations. Two notable trials are:
- KEYNOTE-676: This phase 3 trial is studying the combination of BCG with pembrolizumab (an immunotherapy drug) in patients with high-risk NMIBC.[1]
- POTOMAC: Another phase 3 trial evaluating the combination of BCG with durvalumab (another immunotherapy drug) in BCG-naïve patients with high-risk NMIBC.[2]
These trials aim to determine if combining BCG with other immunotherapies can improve outcomes for patients with bladder cancer.
Efficacy of BCG Treatment
BCG has shown significant efficacy in treating non-muscle invasive bladder cancer. Clinical trials are measuring various outcomes to assess its effectiveness, including:[1][2]
- Complete Response Rate (CRR): The proportion of patients whose cancer completely disappears after treatment
- Disease-Free Survival (DFS): The length of time after treatment that a patient survives without any signs or symptoms of cancer
- Event-Free Survival (EFS): The length of time after treatment that a patient remains free of certain negative events related to their cancer
- Overall Survival (OS): The length of time patients survive after treatment
- Time to cystectomy: The time until a patient requires surgical removal of the bladder
Potential Side Effects
While BCG is generally well-tolerated, it can cause side effects. Common side effects may include:[1][2]
- Urinary frequency and urgency
- Painful urination
- Blood in the urine
- Flu-like symptoms (fever, chills, fatigue)
In rare cases, more serious side effects can occur, such as BCG infection. Patients should report any persistent or severe side effects to their healthcare provider immediately.
Important Considerations for Patients
If you’re considering or undergoing BCG treatment for bladder cancer, keep in mind:
- BCG is a form of immunotherapy, not chemotherapy. It works by stimulating your immune system.
- The treatment requires multiple visits over an extended period, including maintenance therapy.
- Your doctor will monitor your response to treatment through regular cystoscopies and other tests.
- Inform your healthcare provider about all medications you’re taking and any other health conditions you have.
- Clinical trials are ongoing to improve BCG treatment and explore combination therapies. Ask your doctor if you might be eligible for any clinical trials.
BCG therapy has significantly improved outcomes for many patients with non-muscle invasive bladder cancer. However, each patient’s situation is unique, and treatment decisions should be made in consultation with a healthcare team specializing in bladder cancer care.
