• Novel IgG Blocker eliminates heterophilic antibody interference, ensuring clinical-grade purity and mitigating thromboembolic risks

GC Biopharma (006280.KS), a global leader in plasma-derived protein therapies,  announced a significant advancement in the safety monitoring of intravenous immunoglobulin (IVIG). The company has developed and validated a proprietary enzyme-linked immunosorbent assay (ELISA) that effectively mitigates heterophilic antibody interference to precisely measure Factor XI (FXI) levels—a critical impurity linked to thromboembolic risks.

The study, titled "Development and Validation of an Enzyme-Linked Immunosorbent Assay for Measuring Factor XI in Intravenous Immunoglobulin Products by Mitigating Heterophilic Antibody Interference," was published in the April 2026 issue of the Journal of Microbiology and Biotechnology (JMB).

Thromboembolic events associated with IVIG therapy have been linked to activated coagulation factors, prompting global regulatory bodies, including the U.S. FDA, to mandate rigorous monitoring of FXI levels. However, traditional analytical methods often encounter technical limitations due to high-concentration IgG—the primary component of IVIG—interfering with detection signals. This interference frequently results in "false-positive" readings or an inability to detect trace impurities, which can hinder accurate quality control during manufacturing.

To address these challenges, GC Biopharma's R&D team engineered an enhanced assay incorporating a selective IgG Blocker. This innovative approach suppresses non-specific protein reactions, allowing for the isolated and precise measurement of FXI regardless of the IgG concentration in the sample. The platform has been fully validated in accordance with ICH Q2(R2) guidelines.

"By establishing this advanced analytical framework, we have significantly elevated our quality control capabilities for immunoglobulin therapies," said Jae Uk Jeong, Head of R&D at GC Biopharma. "We remain committed to leveraging validated, precision-driven technologies to supply high-quality plasma derivatives to the global market, prioritizing patient safety and clinical excellence above all."