Blood Markers Could Predict CAR T-Cell Therapy Risks
A study shows baseline immune levels may help identify patients at higher risk for cytokine release syndrome.
Updated on Oct. 23, 2026 in Arthritis
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Researchers have identified two blood markers, B-cell counts and IL-6 levels, that help predict the risk of cytokine release syndrome (CRS) in patients receiving CAR T-cell therapy for autoimmune disease. This finding, published in The Lancet Rheumatology on September 25, 2026, could eventually help clinicians better manage treatment risks for individuals undergoing this therapy.
Why it matters
Identifying these baseline markers is a critical step in predicting adverse immune reactions, which occurred in 80% of patients in this study. This research offers clinicians a potential way to stratify risk before starting therapy, potentially improving patient safety and care planning.
In a retrospective cohort study of 108 patients published in The Lancet Rheumatology, researchers found that higher B-cell counts and IL-6 concentrations at baseline were associated with increased risk of cytokine release syndrome. The findings serve as a preliminary identification of potential risk indicators.
The players
The Lancet Rheumatology
A monthly peer-reviewed medical journal that publishes research regarding the treatment and understanding of autoimmune and rheumatic diseases.
The details
CAR T-cell therapy works by reprogramming a patient's own immune cells to attack specific targets, but this process can trigger an aggressive systemic inflammatory response known as cytokine release syndrome. By measuring baseline B-cell counts and IL-6—a protein that acts as a pro-inflammatory mediator—clinicians can potentially identify patients more likely to experience this surge in inflammation. Researchers established specific cutoffs, such as 25.66 B cells/µL and 6.82 pg/mL for IL-6, to distinguish higher-risk groups before treatment commences.
Timeline
The study patient enrollment period began in March 2021.
The study patient enrollment period ended in July 2025.
The study was published online on September 25, 2026.
Health Landscape
This study follows a pattern set by ongoing CAR T-cell therapy clinical development programs that aim to refine safety profiles for autoimmune applications. It marks a shift toward predictive risk assessment to mitigate the common, severe side effects associated with immune-modulating treatments.
If you are considering CAR T-cell therapy for an autoimmune condition, this research highlights the importance of discussing baseline immune screening with your medical team. You may want to ask your physician if your current blood test results offer any insights into your specific risk profile for treatment-related side effects.
The takeaway
Understanding your baseline inflammatory markers is an evolving area of safety in advanced immunotherapy. If you are preparing for such treatments, have a conversation with your physician to understand the specific risks of cytokine release syndrome and what surveillance measures will be used for your care.
Further reading
Learn more about the latest research and standard of care in the Arthritis section.
Source note: This article includes information reported by Medscape.
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