The B15 trial shows EV-Pembro is superior to chemotherapy in muscle-invasive bladder cancer. However, the true benchmark is now the Niagara study (chemo + durvalumab), which already beat chemo alone. The debate will focus on whether EV-Pembro offers a significant enough improvement to become the definitive standard over this new chemo-IO combination.

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Data from trials like Niagara suggests a powerful new paradigm for assessing treatment success. Combining urine tumor DNA (uTDNA) for local disease and circulating tumor DNA (ctDNA) for systemic relapse offers a more dynamic view than traditional pathology and is poised to become the superior surrogate endpoint in bladder cancer trials.

The POTOMAC trial's success adding durvalumab to BCG for non-muscle invasive bladder cancer introduces a major logistical hurdle. Urologists, who typically manage these patients, often lack the expertise to handle systemic immunotherapy side effects, creating uncertainty about which specialty will administer this new standard of care.

The anticipated approval of the highly effective EV-Pembro combination in the perioperative setting will create a new clinical challenge. When these patients eventually relapse years later, clinicians will face a dilemma: re-challenge with the same potent regimen that worked before or switch to older, likely less effective chemotherapies.

Perioperative enfortumab vedotin-pembrolizumab (EV-Pembro) is surprisingly well-tolerated on a per-cycle basis compared to the traditional GEMSYS chemotherapy regimen. This challenges preconceived notions about the toxicity of this powerful combination, though cumulative toxicity over longer durations remains a key factor.

Historically, aggressive variants like micropapillary went directly to surgery. However, recent data suggests these patients do poorly due to micrometastatic disease. The trend is now to give neoadjuvant EV-Pembro to treat systemic disease, even with limited specific evidence.

Expert consensus shows a major paradigm shift: perioperative systemic therapy (like EV-Pembro, scoring 2.9) is the undisputed standard for muscle-invasive bladder cancer. Approaches starting with cystectomy alone now score below 1.8, formally branding them as inferior options.

A key lesson in bladder cancer is that patient attrition is rapid between lines of therapy; many who relapse from localized disease never receive effective later-line treatments. This reality provides a strong rationale for moving the most effective therapies, like EV-pembrolizumab, to earlier settings to maximize the number of patients who can benefit.

With pathologic complete response rates approaching 67% in patients completing neoadjuvant EV-Pembro, a majority of cystectomies are now removing cancer-free bladders. This creates an ethical and clinical imperative to rapidly launch prospective trials to validate bladder preservation strategies and avoid overtreatment.

An expert oncologist identified a pathological complete response (pCR) rate over 50% as the benchmark that would fundamentally alter treatment. The EV Pembro trial's 57% pCR rate crossed this threshold, forcing a shift from a surgery-centric model toward bladder preservation strategies and systemic therapy.

The decision to test Enfortumab Vedotin/Pembrolizumab (EVP) in early-stage muscle-invasive bladder cancer was directly driven by its "flabbergasting" results in the metastatic setting. This highlights a strategy where overwhelming late-stage efficacy signals a therapy should be rapidly moved to earlier, curative-intent settings.