GC Biopharma Enhances IVIG Safety Profile with Advanced Prothrombotic Impurity Detection Technology

• Proprietary analytical method for precise Factor XI (FXI) measurement published in the Journal of Microbiology and Biotechnology
• Novel IgG Blocker eliminates heterophilic antibody interference, ensuring clinical-grade purity and mitigating thromboembolic risks

Yongin, South Korea, 6th April 2026, ZEX PR WIRE — GC Biopharma (006280.KS), a global leader in plasma-derived protein therapies, today 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.”

About GC Biopharma

GC Biopharma (formerly known as Green Cross Corporation) is a biopharmaceutical company headquartered in Yong-in, South Korea. The company has over half a century of experience in the development and manufacturing of plasma derivatives and vaccines, and is expanding its global presence with successful US market entry of Alyglo^®(intravenous immunoglobulin G) in 2024. In line with its mission to meet the demands of future healthcare, GC Biopharma continues to drive innovation by leveraging its core R&D capabilities in engineering of proteins, mRNAs, and lipid nanoparticle (LNP) drug delivery platform to develop therapeutics for the field of rare disease as well as I&I (Immunology & Inflammation). To learn more about the company, visit https://www.gcbiopharma.com/eng/

This press release may contain biopharmaceuticals in forward-looking statements, which express the current beliefs and expectations of GC Biopharma’s management. Such statements do not represent any guarantee by GC Biopharma or its management of future performance and involve known and unknown risks, uncertainties, and other factors. GC Biopharma undertakes no obligation to update or revise any forward-looking statement contained in this press release or any other forward-looking statements it may make, except as required by law or stock exchange rule.

SOURCE GC Biopharma