An advisory panel split 50/50 on a two-year immunotherapy regimen but voted 7-to-1 for a one-year drug with similar efficacy. This reveals that for adjuvant therapies in non-metastatic cancer, halving the treatment duration and toxicity exposure can decisively shift the risk/benefit calculation in favor of approval.

While adding PD-1 inhibitors to standard BCG therapy in high-risk non-muscle-invasive bladder cancer improves event-free survival, it also introduces significant Grade 3 toxicity (around 24%) without mature overall survival data, making its risk-benefit profile questionable.

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.

Current bladder cancer trials often fail to differentiate between patients with primary resistance (never responded) versus acquired resistance (responded, then progressed). Adopting this distinction, common in lung cancer research, could help identify patient subgroups more likely to benefit from immunotherapy re-challenge and refine trial eligibility criteria.

The CREST and Potomac trials showed adding immunotherapy to standard BCG treatment improves event-free survival by only ~5% at 24 months. This modest gain comes with a five-fold increase in significant adverse events, creating a crucial risk-reward discussion for patients.

In high-risk non-muscle invasive bladder cancer (NMIBC), trials like CREST and POTOMAC show adding a systemic immune checkpoint inhibitor to BCG therapy introduces significant toxicity. The benefit is primarily in local control, which may not justify the risk, especially with other effective intravesical options available.

For bladder cancer patients with limited metastatic sites (oligometastatic disease) who respond well to systemic therapy, adding consolidative radiation like SBRT is a reasonable and well-tolerated strategy. This approach, supported by retrospective data and precedent in other cancers like prostate and kidney, aims to improve long-term disease control.

Despite data from kidney cancer showing immunotherapy re-challenge is often ineffective, oncologists admit to using it in urothelial cancer. This highlights a clinical conflict where the desire to use a powerful drug class outweighs the lack of supporting evidence, especially in specific, confusing patient scenarios.

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.