The differing efficacy and toxicity profiles of TROP2 ADCs like sacituzumab govitecan and Dato-DXD suggest that the drug's linker and payload metabolism are crucial determinants of clinical outcome. This indicates that focusing solely on the target antigen is an oversimplification of ADC design and performance.
The interpretation of ctDNA is context-dependent. Unlike in the adjuvant setting, in the neoadjuvant setting, remaining ctDNA positive post-treatment signifies that the current therapy has failed. These high-risk patients need a different therapeutic approach, not an extension of the ineffective one.
High relapse rates (~70%) in surgery-alone arms of recent trials suggest most patients with muscle-invasive bladder cancer (MIBC) already have micrometastatic disease. This reframes the disease, prioritizing early systemic therapy over immediate surgery to achieve control and potential cure.
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.
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.
With highly active agents yielding 30% complete response rates, the immediate goal should be to cure more patients by exploring potent combinations upfront. While sequencing minimizes toxicity, an ambitious combination strategy, such as ADC doublets, offers the best chance to eradicate disease and should be prioritized in clinical trials.
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.
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.