GC Biopharma Presents New Viscosity Research on IVIG Products at ISTH 2025

TEANECK, N.J., July 16, 2025 /PRNewswire/ -- GC Biopharma USA, Inc., a leader in plasma-derived products, announced the presentation of new data on the viscosity of several commercially available 10% intravenous immunoglobulin (IVIG) products at the 2025 International Society on Thrombosis and Haemostasis (ISTH) Congress. Hyperviscosity is a known risk factor for IVIG-associated thromboembolic events (TEEs), and it has been established that IVIG infusions increase plasma viscosity, both acutely and cumulatively.

Viscosity of five commercially available IVIG products was measured at various temperatures ranging from 4°C to 25°C. All products showed consistent decreases in viscosity as temperatures increased suggesting that room-temperature (25°C) infusions could help mitigate viscosity-related risk.

The study measured viscosity using standardized methodologies to normalize immunoglobulin concentrations, enabling an accurate evaluation across products. These findings support evaluating the physical properties of IVIG therapies, such as viscosity and purity, as additional safety parameters in patient populations with increased thrombotic risk.

Suzanne Strasters, MSN, FNP-C, Head of Clinical Education at GC Biopharma USA, who presented the data, said, "These preliminary results warrant further investigation to determine whether there are differences in viscosities between products, which may have important clinical implications for product selection in at-risk patients."

Presented during a poster session at ISTH, the study titled, "Investigation into the Viscosity of Commercial IG Preparations," included analysis of ALYGLO®, OCTAGAM®, GAMUNEX®-C, PRIVIGEN®, and GAMMAGARD LIQUID® using a standardized assay.

ALYGLO® is approved by the U.S. Food and Drug Administration (FDA) for the treatment of primary humoral immunodeficiency (PI) in adults aged 17 and older. ALYGLO® is supported by GC Biopharma's 50-year legacy in plasma product manufacturing with immune globulin therapies distributed in more than 50 countries worldwide.

For more information about ALYGLO and G-XI™ Technology, visit www.alyglo.com or www.gcbiopharma.us.

About ALYGLO®
ALYGLO^® (immune globulin intravenous, human-stwk) is a glycine-stabilized 10% immunoglobulin G (100 mg/mL) for intravenous infusion, manufactured from pooled human plasma from US donors. The manufacturing process includes multiple steps to reduce the risk of virus transmission. These include solvent/detergent treatment and 20 nm nanofiltration. The ALYGLO manufacturing process also uses G-XI^™ Technology, its novel cation exchange (CEX) chromatography, that removes FXIa to undetectable levels (References 1,2).

About GC Biopharma
GC Biopharma (formerly known as Green Cross Corporation) is a biopharmaceutical company that delivers lifesaving and life-sustaining protein therapeutics and vaccines. Headquartered in Yongin, South Korea, GC Biopharma is a leading global plasma protein and vaccine product manufacturer dedicated to quality healthcare solutions for over half a century.

About GC Biopharma USA
GC Biopharma USA, headquartered in Teaneck, NJ, is an operations and distribution company of GC Biopharma, that established its sales, marketing, and business operations in 2018 to serve customers and patients throughout the US. Our foundation is built on the expertise of our parent company GC Biopharma, a leading biopharmaceutical company delivering plasma therapies and vaccines worldwide for more than 50 years. With GC Biopharma USA, GC Biopharma further extends its footprint, bringing its expertise and legacy to the US.

Please see Important Safety Information for ALYGLO on the following pages and refer to the full Prescribing Information (PI) or visit Alyglo.com
If you have an inquiry related to drug safety, or to report adverse events, please contact GC Biopharma USA at 1-833-426-6426 or email medicalinfo@gcbiopharmausa.com. You can also visit FDA.gov/medwatch or call 1-800-FDA-1088.

INDICATION
ALYGLO® is indicated for the treatment of primary humoral immunodeficiency (PI) in adults aged 17 years and older. This includes, but is not limited to, congenital agammaglobulinemia, common variable immunodeficiency (CVID), Wiskott-Aldrich syndrome, and severe combined immunodeficiencies.

IMPORTANT SAFETY INFORMATION

WARNING: THROMBOSIS, RENAL DYSFUNCTION and ACUTE RENAL FAILURE

• Thrombosis may occur with immune globulin intravenous (IGIV) products, including ALYGLO. Risk factors may include: advanced age, prolonged immobilization, hypercoagulable conditions, history of venous or arterial thrombosis, use of estrogens, indwelling vascular catheters, hyperviscosity, and cardiovascular risk factors.
• Renal dysfunction, acute renal failure, osmotic nephropathy, and death may occur with the administration of IGIV products in predisposed patients.
• Renal dysfunction and acute renal failure occur more commonly in patients receiving IGIV products containing sucrose. ALYGLO does not contain sucrose.
• For patients at risk of thrombosis, renal dysfunction or renal failure, administer ALYGLO at the minimum dose and infusion rate practicable. Ensure adequate hydration in patients before administration. Monitor for signs and symptoms of thrombosis and assess blood viscosity in patients at risk for hyperviscosity.

• Contraindications: ALYGLO is contraindicated in patients who have a history of anaphylactic or severe systemic reaction to the administration of human immune globulin and in IgA-deficient patients with antibodies to IgA and a history of hypersensitivity.
• Hypersensitivity: In case of hypersensitivity, discontinue infusion immediately and institute appropriate treatment. Epinephrine should be available for immediate treatment of severe acute hypersensitivity reactions.
• Hyperproteinemia, Increased Serum Viscosity, and Hyponatremia: Hyperproteinemia, increased serum viscosity, and hyponatremia may occur.
• Aseptic Meningitis Syndrome (AMS): Aseptic meningitis syndrome (AMS) may occur, especially with high doses or rapid infusion. AMS usually begins within several hours to 2 days following ALYGLO treatment. Discontinuation of treatment has resulted in remission of AMS within several days without sequelae.
• Hemolysis: Delayed hemolytic anemia due to enhanced red blood cell (RBC) sequestration and acute hemolysis consistent with intravascular hemolysis have been reported. Cases of severe hemolysis-related renal dysfunction/failure or disseminated intravascular coagulation have occurred following infusion of IGIV. Closely monitor patients for clinical signs and symptoms of hemolysis, particularly patients with risk factors.
• Transfusion-Related Acute Lung Injury: Noncardiogenic pulmonary edema (transfusion-related acute lung injury [TRALI]) may occur. TRALI is characterized by severe respiratory distress, pulmonary edema, hypoxemia, normal left ventricular function, and fever. Patients with TRALI may be managed using oxygen therapy with adequate ventilator support. Monitor patients for pulmonary adverse reactions.
• Transmissible Infectious Agents: Because ALYGLO is made from human blood, it may carry a risk of transmitting infectious agents (eg, viruses, the variant Creutzfeldt-Jakob disease [vCJD] agent and, theoretically, the Creutzfeldt-Jakob disease [CJD] agent).
• Interference with Laboratory Tests: After infusion of immunoglobulin, the transitory rise of the various passively transferred antibodies in the patient's blood may yield positive serological testing results, with the potential for a misleading interpretation.
• Adverse reactions (observed in ≥ 5% of study subjects) were headache, nausea/vomiting, fatigue, nasal/sinus congestion, rash, arthralgia, diarrhea, muscle pain/aches, infusion site pain/swelling, abdominal pain/discomfort, cough, and dizziness.
• It is recommended that ALYGLO be administered separately from other drugs or medications.

This press release may contain forward-looking statements that express the current beliefs and expectations of the management at GC Biopharma and GC Biopharma USA. Such views do not represent any guarantee by either entity or its government of future performance and involve known and unknown risks, uncertainties, and other factors. GC Biopharma and GC Biopharma USA undertake no obligation to update or revise any forward-looking statement contained in this press release or any other forward-looking statements they may make, except as required by law or stock exchange rule.

Reference: 1. Kang GB, Huber A, Lee J, et al. Cation exchange chromatography removes FXIa from a 10% intravenous immunoglobulin preparation. Front Cardiovasc Med. 2023;10:1253177. 2. ALYGLO Prescribing Information. GC Biopharma; 2023.

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SOURCE GC Biopharma USA Inc.