ADC Therapeutics disclosed Phase 3 confirmatory data from LOTIS-5 for Zynlonta plus rituximab in relapsed or refractory diffuse large B-cell lymphoma. The regimen met the progression-free survival endpoint, but the company reported a death imbalance—27 deaths in the treatment arm versus nine in the control arm—without claiming a direct causal link to the study regimen. While ADC said there was no overall survival benefit and characterized the deaths as treatment-emergent adverse events, analysts flagged the elevated mortality as a major issue that could complicate future utilization and regulatory discussions aimed at full approval. The update illustrates how confirmatory trial requirements can tighten the acceptance bar: even a positive efficacy signal may not translate into label expansion if safety-to-benefit interpretation becomes difficult.