A landmark pharmacovigilance analysis of nearly five million adverse-event reports found liver injury after CAR T-cell therapy is predominantly early and correlated with cytokine release syndrome. The study reports an overall signal driven by early events, while also identifying a persistent CRS-independent signal for idecabtagene vicleucel that warrants prospective evaluation. The analysis provides a data-driven lens on toxicity timing rather than relying only on trial-era observations. For CAR T programs, the findings emphasize monitoring windows and pharmacovigilance follow-up for hepatic complications, especially in patient subsets with differing CRS risk. Clinically, the work supports refining safety protocols and may inform how centers triage liver enzyme changes during early post-infusion management.