Experts believe the stark difference in complete response rates (5% vs 30%) between two major ADC trials is likely due to "noise"—variations in patient populations (e.g., more upper tract disease) and stricter central review criteria, rather than a fundamental difference in the therapies' effectiveness.
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The negative ANSA-RAD trial, when contrasted with the positive STAMPEDE trial, demonstrates that patient selection is paramount in adjuvant therapy. The difference in outcomes was driven by risk definition, not the drug. This reinforces that "negative" trials are clinically vital for defining which patient populations do not benefit, preventing widespread overtreatment.
The CREST trial showed benefit driven by patients with carcinoma in situ (CIS), while the Potomac trial showed a lack of benefit in the same subgroup. This stark inconsistency demonstrates that subgroup analyses, even for stratified factors, can be unreliable and are a weak basis for regulatory decisions or label restrictions.
The panel reviews advanced, second-line ADC trials in China using novel targets and payloads. An expert remarks that these are the drugs and questions the US and Europe may only begin to study in two to three years, signaling a significant shift in the global oncology R&D landscape.
Experts question the efficacy of sequencing ADCs like EV (Nectin-4 target) and DV (HER2 target) because they share the same MMAE chemo payload. Since resistance is often tied to the payload, not the target antibody, switching targets may not overcome resistance, though anecdotal responses have been observed.
The failure of the TROPiCS-04 trial for sacituzumab govitecan may not indicate the TROP2 ADC class is ineffective. Experts suggest problems with dosing and toxicity management (e.g., neutropenia) during the trial could be the real culprit, arguing that the drug class still holds promise.
Experts question if HER2 status truly predicts ADC efficacy in urothelial cancer. The benefit seen across low-expression levels suggests HER2's main role may be simply to target the chemo payload to cancer cells, rather than indicating a specific biological dependency.
Sepsis is not a monolithic condition. The failure of more than 100 immunomodulatory drug trials is likely because they treated all patients the same. The future of sepsis treatment mirrors oncology: subtyping patients based on their specific inflammatory profile to match them with a targeted therapy.
A significant criticism of the pivotal KEYNOTE-564 trial is that only half the patients in the control arm received standard-of-care immunotherapy upon relapse. This lack of subsequent optimal treatment complicates the interpretation of the overall survival benefit, raising questions about its true magnitude.
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 successful KEYNOTE-564 trial intentionally used a pragmatic patient selection model based on universally available pathology data like TNM stage and grade. This approach avoids complex, inconsistently applied nomograms, ensuring broader real-world applicability and potentially smoother trial execution compared to studies relying on more niche scoring systems.