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Breakthrough Study: RainSure Digital PCR Empowers the World's First Multicenter Study of Glofitamab in Primary CNS Lymphoma

Breakthrough Study: RainSure Digital PCR Empowers the World's First Multicenter Study of Glofitamab in Primary CNS Lymphoma

Primary central nervous system lymphoma (PCNSL) is a highly aggressive clinical entity. For relapsed or refractory (R/R) patients, traditional therapies often yield a poor survival time of only 2 to 6 months. With the advent of the immunotherapy era, the combination of bispecific antibodies and CAR-T therapy has emerged as a new hope to overcome this challenge.

Recently, the teams of Professor Junmin Chen and Professor Zhiyong Zeng from the First Affiliated Hospital of Fujian Medical University, in collaboration with Professor Youwen He from Duke University, published their latest research findings in the top-tier hematology journal American Journal of Hematology. The paper is titled "Multicenter Real-World Analysis of Glofitamab in Relapsed/Refractory Primary CNS Lymphoma: Clinical Activity, CNS Penetration, and ctDNA Dynamics".

This study not only validates the exceptional efficacy of the CD20/CD3 bispecific antibody glofitamab in PCNSL, but it also utilizes RainSure Scientific's digital PCR (dPCR) technology to reveal the kinetic evolution of CAR-T cells in the cerebrospinal fluid and the mechanisms of neurotoxicity with unprecedented sensitivity.

Core Highlights: Remarkable Efficacy of Bispecific Antibody Induction

The study included 16 heavily pretreated patients with R/R PCNSL (with a median of 3 prior lines of therapy). The results showed:

  • High Response Rate: The objective response rate (ORR) for glofitamab monotherapy induction reached 75%, with a complete response (CR) rate of 50%.
  • Survival Breakthrough: The median progression-free survival (PFS) reached 15.4 months, significantly outperforming past conventional therapies.
  • CNS Penetration: Paired sample testing confirmed that glofitamab can penetrate the blood-brain barrier, with maximum drug concentrations in the cerebrospinal fluid (CSF) reaching 25.42 ng/mL.

Precision Monitoring: RainSure Digital PCR Shines

In the exploratory analysis of this study, accurately tracking post-treatment circulating tumor DNA (ctDNA) and CAR-T cell expansion was a core technical challenge. The research team utilized the RainSure Scientific DropDx dPCR system, accomplishing key quantitative tasks.

1. The "Detective" of Trace CAR-T Expansion

In patients receiving CAR-T consolidation therapy, researchers used RainSure dPCR to perform duplex amplification targeting the FMC63 scFv sequence and the RPP30 reference gene.

  • Highly Sensitive Quantification: dPCR provided absolute copy numbers per µg of DNA, capturing the minute expansion of CAR-T cells in the CSF and peripheral blood earlier and more accurately.
  • Revealing Toxicity Mechanisms: Dynamic dPCR monitoring showed that two patients who developed fatal immune effector cell-associated neurotoxicity syndrome (ICANS) both exhibited significant CAR-T cell re-expansion within the CSF. For one patient, this marked expansion in the CSF closely followed the re-dosing of glofitamab.

2. Deep Synergy Between Molecular Response and Imaging

The molecular monitoring supported by RainSure's technology platform found that early clearance of CSF ctDNA was highly consistent with radiographic response. Patients who turned negative early indicated a longer survival period, whereas persistent or re-emergent ctDNA positivity was an early warning signal for disease progression or the onset of fatal neurotoxicity.

Conclusion: RainSure Technology Empowers Precision Medicine

Through real-world multicenter data, this study demonstrated the immense potential of glofitamab in R/R PCNSL. Relying on its high sensitivity and robust performance, RainSure digital PCR technology demonstrated core value in testing complex clinical samples like cerebrospinal fluid. It provides "gold standard" technical support for the individualized monitoring of immune cell therapies.

As precision medicine continues to deepen, digital PCR will undoubtedly play an even more critical role in evaluating the efficacy and predicting the safety of hematologic malignancies.

Reference: Yang A, Dong J, Deng X, et al. Multicenter Real-World Analysis of Glofitamab in Relapsed/Refractory Primary CNS Lymphoma: Clinical Activity, CNS Penetration, and ctDNA Dynamics. American Journal of Hematology. 2026; 0:1-13. https://doi.org/10.1002/ajh.70342.