CAR-T toxicity management shifts toward phenotype- and mechanism-based intervention
CAR-T toxicity management is shifting toward phenotype- and mechanism-based intervention. Key issues include CRS, ICANS, IEC-HS, and long-term risks of cytopenia and infection.
CAR-T toxicity management in hematologic oncology is shifting from a "one-size-fits-all" approach to phenotype- and mechanism-based intervention. Key domains highlighted for mitigating CAR-associated adverse effects included cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome, and long-term risks of cytopenia and infection.
Cytokine Release Syndrome (CRS) is a risk model, with events influenced by factors including product design, tumor context, target antigens, and host immune reserves. The incidence of CRS may differ between CAR-T products such as obecabtagene autoleucel (obe-cel; Aucatzyl) and brexucabtagene autoleucel (brexu-cel; Tecartus), and selection of CAR T-cell therapies is based on toxicity management rather than efficacy alone.
Immune Effector Cell-Associated Neurotoxicity Syndrome (ICANS) was outlined as an umbrella phenotype rather than a single mechanism. Different mechanisms indicate that blanket steroid escalation may not be optimal for every phenotype, and phenotype-based classification, biomarker guidance, and personalized anti-inflammatory strategies may be necessary to optimize ICANS management.
Immune Effector Cell–Associated Hemophagocytic Lymphohistiocytosis–like Syndrome (IEC-HS) was described as an underrecognized threat. Incidence of IEC-HS in multiple myeloma and chronic lymphocytic leukemia may challenge tocilizumab (Actemra)-based algorithms, and mitigation strategies involving anakinra (Kineret) and ruxolitinib (Jakafi) may be more rational than IL-6 inhibition alone.
For long-term risks of cytopenia and infection, CAR-HEMATOTOX criteria may help predict prolonged severe neutropenia before cellular therapy. Phase 3 trial (NCT03073967) data for pritelivir in refractory herpes simplex virus infection suggest a shift from inpatient to outpatient care and a reduction in toxicity and disruption to cellular therapy plans.