What Is a Clinical Trial?
A clinical trial is a type of research study that helps doctors learn about diseases and come up with new treatments. By joining a clinical trial, you can get access to cutting-edge experimental medications, which can be especially helpful when you have a condition that's hard to treat, like advanced bladder cancer.
Clinical Trials for Advanced Bladder Cancer
Most cases of advanced bladder cancer can't be cured, and many people go through several different types of treatment to try to slow its progression and control their symptoms. Doctors are constantly trying to improve treatments to get better outcomes.
Recent clinical trials have led to drug breakthroughs. A combination of two newer types of medications – a targeted therapy drug called an antibody-drug conjugate and an immunotherapy drug called a checkpoint inhibitor – is now the recommended treatment for many advanced stages of bladder cancer. And an immune checkpoint inhibitor is also part of the main treatment for earlier stages of muscle-invasive bladder cancer.
Researchers are focused on learning the best uses for these and other types of drugs, and developing new ones. Here's some of what they're investigating:
Drug conjugates
This type of drug combines a powerful anti-cancer medicine with a carrier that attaches to a target on a cancer cell. They're designed to do less damage to healthy cells than other treatments. Several of these drugs are being tested, including:
Antibody-drug conjugates. These use a protein called an antibody to find and attach to another protein called an antigen on a bladder cancer cell, delivering the chemotherapy directly to it. The FDA has approved enfortumab vedotin (Padcev) and trastuzumab deruxtecan (Enhertu). Among others that scientists are studying are:
- Datopotamab deruxtecan (Dato-DXd)
- Disitamab vedotin (Aidixi)
- Sacituzumab govitecan (Trodelvy)
- Sacituzumab tirumotecan (sac-TMT)
- Tisotumab vedotin (Tivdak)
Bicycle toxin conjugates. Like antibody-drug conjugates, these use a string of molecules called a peptide, which is smaller than an antibody, to find and attach to cancer cells. Drugs of this type being tested include zelenectide pevedotin.
Other targeted therapy
Other kinds of targeted therapy include single-agent drugs that can shut off certain processes that cancer cells need to survive and spread. The FDA has approved one such drug, erdafitinib (Balversa), called an FGFR inhibitor. It blocks the action of defective proteins called fibroblast growth factor receptor kinases.
More drugs are in development that have that same target. Other targets under study include checkpoint kinase 1 (CHK1), PARP, and a protein called KIF18A.
Immunotherapy
Immunotherapy uses the power of your body's immune system to kill cancer cells. For treating advanced bladder cancer, clinical trials are focused on:
Checkpoint inhibitors. These kinds of drug blocks the ability of cancer cells to disable your body's immune response. Researchers are now trying to figure out how to tell which patients they'll work for.
Bi-specific T-cell engagers. These drugs bring cancer-fighting T cells directly to cancer cells by attaching themselves to both types of cells.
Cancer vaccines. These teach your immune system to find and fight the cancer by exposing you to manufactured versions of proteins on the cancer cells.
Oncolytic viruses. Certain viruses can be engineered to infect and kill cancer cells. Plus, they can help your immune system recognize and attack the tumor.
Drug combinations
No single treatment for advanced bladder cancer works well for everyone. Many people end up having combinations of treatments. As new drugs are developed, researchers are testing them in new combinations, like using multiple checkpoint inhibitors or multiple antibody-drug conjugates, or adding a kinase inhibitor to an antibody-drug conjugate.
Should You Consider a Clinical Trial for Advanced Bladder Cancer?
Anyone can apply to take part in a clinical trial with their doctor's approval, no matter the stage of the cancer or where you are in the treatment process. But in some situations, a clinical trial may be your best treatment option. Experts encourage you to consider one if:
- You have stage IV (metastatic) bladder cancer.
- You've tried other treatments for advanced bladder cancer, and it stays the same or gets worse.
- The cancer comes back after treatment.
Joining a Clinical Trial
The first step is to talk with your doctor. They can tell you what type of experimental drug could help you and whether it would be safe for you to take part.
How to find a clinical trial
You can find out if there are clinical trials you might join in many ways:
Ask your doctor. They may be connected to a hospital that's doing a trial, or they may know about a local trial you might be right for.
Check with local universities or hospitals. Clinical trials are often done through medical schools and cancer research centers, and they usually have a list of ongoing clinical trials on their websites.
Look online. You can find a number of databases where you can search for clinical trials by location, condition, and type of treatment. Sources include ClinicalTrials.gov, the National Cancer Institute, and the Bladder Cancer Advocacy Network.
Contact a drug company. Drugmakers often have a way to connect you with trials of the drugs they're testing on their websites.
If you see one that looks interesting, you'll want to check whether it's enrolling new patients, and also some basic information like:
- Who's sponsoring the trial
- Where it's taking place
- How long it will go on
You also need to understand what it means when they list the phase of the trial.
Phase I trials use a very small number of people to test a drug for safety.
Phase II trials use a larger number of people to see if the treatment works.
Phase III trials test the new treatment against the standard treatment. Researchers try to see how the effectiveness and side effects compare. These trials usually involve hundreds of people. In cancer drug trials, some get the standard treatment plus the new treatment, and others get the standard treatment alone or combined with a fake drug called a placebo.
Phase IV trials come after the FDA has approved a new treatment. They look at long-term safety and effectiveness.
Are you eligible?
Once you've found a clinical trial you'd like to join, you'll talk with a member of the research team to see if it's a good fit for you. Trials have certain types of patients they're looking for. With advanced bladder cancer, they'll want to know things like:
- Whether the cancer is muscle invasive or non-muscle invasive
- Whether you're newly diagnosed or have already started treatment
- If the cancer cells have certain gene mutations
- Which treatments you've already had and how well they worked
- If the cancer is getting worse or has come back after other treatment
How clinical trials work
Before you enroll in a clinical trial, the research team will give you details about the study goals, procedure, possible benefits and risks, and your responsibilities. Take as much time as you need to read over the information and ask questions. You'll then sign an informed consent document that says you understand everything and agree to take part.
During the study, you'll have tests and treatments on a schedule that's laid out by the research team.
Clinical trials usually don't cost you anything to take part, and you may get paid for your time or travel expenses. Your insurance will probably cover the standard treatment, while the drug company will provide the study medication and cover any added tests and doctor visits.
Researchers take care to protect your private information, and you are free to quit at any time for any reason.
Pros and Cons of Clinical Trials
On the plus side, you may be able to try the latest treatments for advanced bladder cancer that aren't available to other people. While there's no guarantee, the test drug could work better for you.
There are also risks. Experimental drugs are tested for safety before people get them, but it's possible you could have serious side effects. You'll likely have extra doctor visits, tests, and travel.
Ultimately, it's up to you whether you think the possible benefits outweigh the risks.
Show Sources
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SOURCES:
National Comprehensive Cancer Network: "NCCN Guidelines for Patients: Bladder Cancer 2025."
American Cancer Society: "Clinical Trials,""Immunotherapy for Bladder Cancer,""Targeted Therapy Drugs for Bladder Cancer," "Treatment of Bladder Cancer, Based on the Stage and Other Factors,""Finding a Clinical Trial,""Phases of Clinical Trials,""Things to Consider Before Taking Part in a Clinical Trial,""Being Part of a Clinical Trial."
National Cancer Institute: "What Are Clinical Trials?""Advances in Bladder Cancer Research,""Oncolytic Virus Therapy: Using Tumor-Targeting Viruses to Treat Cancer,""Clinical Trial Facts,""Bladder Cancer Treatment (PDQ) – Health Professional Version,""What to Expect During a Clinical Trial,""How Do Clinical Trials Work?""Participate in Cancer Treatment Trials," "Who Pays for Clinical Trials?"
ClinicalTrials.gov.
Cureus:"Immune Checkpoint Inhibitors as a Treatment Option for Bladder Cancer: Current Evidence."
Frontiers in Immunology: "Antibody-drug conjugates as game changers in bladder cancer: current progress and future directions."
Therapeutic Advances in Urology: "Systematic review of recent advancements in antibody-drug and bicycle toxin conjugates for the treatment of urothelial cancer."
Cancer Cytopathology: "Insights on recent innovations in bladder cancer immunotherapy."
Memorial Sloan Kettering Cancer Center: "Cancer Vaccines: The Types, How They Work, and Which Cancers They Treat."
