Extrapolating from the metastatic setting, clinicians should anticipate that most patients on the 9-cycle perioperative EV-pembrolizumab regimen will require dose reductions or holds. Cumulative peripheral neuropathy is the primary driver, suggesting a need for proactive, individualized dose management rather than strict adherence to the trial's protocol.
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.
Circulating tumor DNA (ctDNA) is a powerful biomarker for identifying high-risk bladder cancer patients. However, its imperfection presents a new clinical dilemma: with a ~12% relapse rate even in ctDNA-negative patients, clinicians must decide whether to withhold adjuvant therapy and accept that risk, or overtreat the 88% who are likely cured.
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.
While the TAR-200 gemcitabine-releasing device showed lower efficacy than systemic EV-pembrolizumab, its value proposition is logistical simplicity. As a treatment administered entirely by urologists in-office via cystoscopy, it offers a less complex and potentially less toxic alternative, making it an attractive option based on practice workflow rather than superior outcomes alone.
While KEYNOTE-905 showed dramatic survival benefits with neoadjuvant plus adjuvant EV-pembrolizumab, its design makes it impossible to isolate the benefit of each phase. The high (57%) pathologic complete response after neoadjuvant therapy alone suggests many patients may be overtreated with adjuvant cycles, risking unnecessary long-term toxicity like neuropathy.