Using an unsupervised computational approach blind to clinical outcomes, a group of researchers developed INFLAmmation MIXture Model (InflaMix), a predictive model, designed as a point-of-care clinical tool that uses a novel, unbiased approach to characterise a preinfusion inflammatory signature, encouraging new mechanistic hypotheses for CAR-T resistance in patients with non-Hodgkin lymphoma (NHL).
With further prospective validation, the authors envision InflaMix being implemented in clinical practice and trial design to identify patients at high risk of treatment failure and support informed risk-benefit discussions for prophylactic or consolidative therapies. The predictive capacity of InflaMix complements existing toxicity prediction tools and may enhance multimodal prediction of CAR-T outcomes according to Dr. Roni Shouval of the Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College in New York, NY, US, and Chaim Sheba Medical Center, Tel-Hashomer, affiliated with Faculty of Medicine, Tel Aviv University in Tel Aviv, Israel and colleagues, who reported the findings on 1 April 2025 in the Nature Medicine.
CAR-T treatment failure remains a substantial challenge in large B-cell lymphoma. The benefits of CAR-T treatment must also be balanced against the substantial risk of toxicities, including cytokine release syndrome (CRS), neurotoxicity, infectious complications, prolonged cytopenias and death. There is a clinical need for predictive tools that can be implemented at different decision points to identify patients at high-risk of CAR-T treatment failure, the authors explained in the background.
Poor clinical outcomes have been correlated with factors such as tumour TP53 mutation, higher disease burden, elevated inflammatory markers, lower CAR-T cell expansion, and product CCR7+CD45RA+ T cell enrichment before infusion. Although genomic, radiomic and CAR-T cell immunophenotyping evaluations are not widely available in clinical practice, laboratory, and cytokine measures of systemic inflammation via routine blood tests have been studied as accessible prognostic biomarkers.
Prelymphodepletion levels of inflammatory markers such as interleukin-6 (IL-6), ferritin, and lactate dehydrogenase (LDH) have been inversely associated with durable response, CAR-T expansion and immunotoxicity. These markers are surrogates for myeloid immune activation, tumour metabolic activity or cellular turnover. Moreover, IL-6 and IL-10 exhibit pleiotropic effects within the lymphoma microenvironment, including upregulation of regulatory T cells, inhibition of myeloid effectors and promotion of T cell exhaustion.
The authors wrote that inflammation has also been linked with toxicity indices such as the modified EASIX (Endothelial Activation and Stress Index) and CAR-HEMATOTOX, which combine inflammatory markers, such as C-reactive protein (CRP), and blood cell counts to predict cytopenias, CRS and immune-effector cell-associated neurotoxicity syndrome (ICANS). However, there are no validated biomarkers designed to predict the likelihood of relapse or disease progression following CAR-T cell therapy.
InflaMix, an unsupervised Gaussian mixture model, defines a preinfusion laboratory and cytokine profile, evaluated at the preinfusion timepoint, that strongly correlates with and predicts poor disease response and survival after CD19-directed CAR-T therapy in NHL across multiple patient cohorts.
This point-of-care tool, requiring only a single blood test, offers an unbiased quantitative assessment of 14 blood markers, 11 of which are routinely assayed for patients with lymphoma. It can also be implemented when only six specific measures (haemoglobin [Hgb], LDH, CRP, aspartate aminotransferase [AST], alkaline phosphatase [ALP] and albumin) are available.
InflaMix integrates pre-CAR-T infusion laboratory and cytokine measures capturing inflammation and end-organ function. Developed using a cohort of 149 patients with NHL, InflaMix revealed an inflammatory signature associated with a high risk of CAR-T treatment failure, including increased hazard of death or relapse (hazard ratio 2.98, 95% confidence interval 1.60–4.91; p < 0.001).
Three independent cohorts comprising 688 patients with NHL from diverse treatment centres were used to validate the approach. InflaMix consistently and reproducibly identified patients with a higher likelihood of disease relapse and mortality, and it provided supplementary predictive value beyond established prognostic markers, including tumour burden.
Moreover, InflaMix exhibited robust performance in cases with missing data, maintaining accuracy when considering only six readily available laboratory measures. These findings show that InflaMix is a valuable tool for point-of-care clinical decision-making in patients with NHL undergoing CAR-T therapy.
Beyond establishing a strong association between cluster assignment and clinical outcomes in the derivation cohort, the study team validated this association across three independent cohorts totalling 688 patients, each differing in clinical characteristics, geography, NHL subtypes and CAR-T products.
Prior studies have linked inflammatory markers and toxicity. The latest findings extend previous work by emphasising a role for inflammation in CAR-T treatment failure, and introducing a robust, easily implementable bedside tool for risk stratification.
Due to its robust performance with incomplete data, InflaMix can also be used effectively with a limited six-lab panel (albumin, AST, ALP, Hgb, LDH and CRP) and is easily implemented in clinical settings via an online calculator), reducing barriers to point-of-care use that often hinder other prognostic tools.
This research was supported in part by the US National Institutes of Health/National Cancer Institute award, MSK Support Grant, grants and awards from other non-profit entities.
Reference
Raj SS, Fei T, Fried S, et al. An inflammatory biomarker signature of response to CAR-T cell therapy in non-Hodgkin lymphoma. Nature Medicine; Published online 1 April 2025. DOI: https://doi.org/10.1038/s41591-025-03532-x