FDA Approves Personalized Blood-Test Guided Immunotherapy for Bladder Cancer, Backed by Dana-Farber Science

When patients with bladder cancer complete treatment that is intended to cure the cancer, they may be left wondering if there is anything else they should do to keep the cancer from coming back. For patients with muscle invasive bladder cancer – where the disease is at a higher risk of coming back than early-stage bladder cancer – that answer is yes.

They can have a blood test that will help determine if they should receive additional treatment after surgery (called adjuvant therapy) to keep the cancer at bay.

This personalized approach to treatment after surgery was approved by the U.S. Food and Drug Administration (FDA) in May 2026, following a phase 3 clinical trial co-led by a Dana-Farber expert. With the approval, patients deemed to be at a high risk of recurrence based on the results of the blood test can now receive immunotherapy with atezolizumab after surgery to reduce that risk. Those found to be at low risk are monitored with regular, repeated blood tests.

The blood test measures circulating tumor DNA (ctDNA), fragments of tumor DNA floating in the blood stream, to detect the presence of cancer even when it is too small to be visible on scans. The test, called Signatera™, is personalized to rapidly detect the patient’s unique tumor DNA.

“I have patients who are concerned after surgery and want to know what they should do,” says Joaquim Bellmunt, MD, PhD, director of the bladder cancer center at Dana-Farber. “This ctDNA test is a good predictor of outcomes, and now it provides a personalized approach to help determine which patients are most likely to benefit from adjuvant atezolizumab and which can be safely monitored without immediate treatment.”

Dana-Farber-led Science

The approval is backed by evidence from a phase 3 clinical trial co-led by Bellmunt called IMvigor011. In that trial, patients testing positive for ctDNA after surgery received either atezolizumab or a placebo. Those who received atezolizumab had a 36% lower risk of disease recurrence than those who received placebo. This benefit was observed regardless of whether they were ctDNA-positive immediately after surgery or if ctDNA-positivity emerged during screening up to a year after surgery.

“By selecting patients based on ctDNA, we see a benefit not only for disease-free survival but also for overall survival with atezolizumab,” says Bellmunt. ”Unlike previous adjuvant immunotherapy trials, which treated all high-risk patients regardless of biomarker status, IMvigor011 is the first phase 3 study to demonstrate that selecting patients based on ctDNA identifies those who derive a survival benefit from adjuvant immunotherapy.”

Patients who remained ctDNA negative received no additional treatment. Of those patients, 89% remained disease-free and more than 90% were still living at a median follow up of 21.8 months.

Atezolizumab is an immune checkpoint inhibitor that targets a marker called PD-L1 on cancer cells, unmasking them so that immune cells can recognize them. As with other immune checkpoint inhibitors, some patients experience side effects that can affect their quality of life.

“What these findings tell us is that this ctDNA test is detecting minimum residual disease and can identify patients who still have bladder cancer after surgery and might benefit from receiving atezolizumab,” said Bellmunt. “Further, it suggests that patients who are persistently ctDNA-negative have a low risk of recurrence and can be spared from unnecessary treatment and its potential toxicities, while continuing careful surveillance with serial ctDNA testing.”