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.
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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.
In the absence of direct evidence for adjuvant therapy in high-risk, non-clear cell kidney cancers, clinicians may justify off-label treatment by extrapolating from the drug's known efficacy in the metastatic setting for that specific histology. This highlights the difficult risk-benefit calculations made daily in data-poor clinical scenarios.
In a data-free zone, a survey of 78 US oncologists revealed an emerging consensus to wait six months before re-challenging with EV-Pembro after prior immunotherapy. This demonstrates how clinical practice norms can form around arbitrary time points when definitive evidence on optimal treatment-free intervals is lacking.
In adjuvant bladder cancer trials, ctDNA status is both prognostic and predictive. Patients with positive ctDNA after surgery are at high risk of relapse but benefit from immune checkpoint inhibitors. Conversely, ctDNA-negative patients have a lower risk and derive no benefit, making ctDNA a critical tool to avoid unnecessary, toxic therapy.
Developers often test novel agents in late-line settings because the control arm is weaker, increasing the statistical chance of success. However, this strategy may doom effective immunotherapies by testing them in biologically hostile, resistant tumors, masking their true potential.
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.
An expert argues forcefully that the PD-L1 biomarker should be "ditched" in bladder cancer. Citing its repeated failure to predict overall survival benefit across multiple major trials, it is deemed an oversimplified and unreliable tool that leads to both over- and under-treatment of 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.
The success of new treatments like immunotherapy and ADCs leads to more patients achieving a deep response. This high efficacy makes patients question the necessity of a radical cystectomy, a life-altering surgery, creating an urgent need for data-driven, bladder-sparing protocols.
The speakers highlight that negative trials in kidney cancer, which showed no benefit to immunotherapy re-challenge, were "super helpful." This is because they provided definitive evidence to stop a common clinical practice that was not helping patients and potentially causing harm, underscoring the constructive role of well-designed "failed" studies.