VarmX and Rentschler Biopharma Expand Partnership for Phase III Development of Novel Coagulation Therapy VMX-C001
Key Insights
VarmX (search) and Rentschler Biopharma (search) have expanded their collaboration to manufacture VMX-C001, a modified factor X protein designed to bypass direct oral anticoagulants, for Phase III development and potential commercialization.
VMX-C001 received FDA Fast Track Designation in September 2025 and is preparing for the global Phase III EquilibriX-S trial in urgent surgery, expected to begin in early 2026.
Manufacturing will transition from Rentschler's Germany facility to its Milford, Massachusetts site to support late-stage clinical and commercial production needs.
VarmX (search) and contract development and manufacturing organization (CDMO) Rentschler Biopharma (search) have announced an expanded partnership to advance VMX-C001, a novel coagulation therapy designed to restore blood clotting in patients taking direct oral anticoagulants who require emergency surgery. The collaboration extends their existing relationship from early development to Phase III clinical supply and potential commercialization.
VMX-C001 is a modified, human factor X protein engineered to be insensitive to activated factor Xa (search) (FXa) direct oral anticoagulants (DOACs), effectively bypassing their anticoagulant activity and rapidly restoring the coagulation cascade. The therapy addresses a critical unmet medical need for patients on FXa DOACs who experience severe bleeding (search) or require urgent surgical intervention.
Regulatory Momentum and Clinical Development
The U.S. Food and Drug Administration awarded VMX-C001 Fast Track Designation in September 2025, recognizing its potential to address an urgent medical need. The therapy also received a Phase 1 waiver from Japan's Pharmaceuticals and Medical Devices Agency (PMDA) in September 2025.
VarmX (search) plans to initiate its global Phase III EquilibriX-S trial in urgent surgery in early 2026, evaluating VMX-C001's ability to rapidly restore coagulation in patients taking any FXa DOAC undergoing urgent surgery. The announcement follows VarmX's global strategic collaboration and option agreement with CSL (search) signed in September 2025.
Manufacturing Partnership Evolution
Rentschler Biopharma (search) has supported VMX-C001's early development since 2022 at its biopharmaceutical manufacturing site in Laupheim, Germany. Under the expanded partnership, all subsequent Phase III clinical supply, including process validation, will be transferred to Rentschler's manufacturing facility in Milford, Massachusetts, as part of the transition into late-stage clinical and commercial production.
"Manufacturing readiness is key as we prepare to commence our landmark global EquilibriX-S Phase III trial," said John Glasspool, CEO of VarmX (search). "We're pleased to extend our partnership with Rentschler Biopharma (search) as we drive VMX-C001 towards becoming a new treatment option for the substantial number of patients on FXa DOACs who need emergency surgery."
Benedikt von Braunmühl, CEO of Rentschler Biopharma (search), emphasized the partnership's significance: "We are honored to continue our collaboration with VarmX (search), which reflects exactly what Rentschler Biopharma stands for: high-impact technical expertise, long-term partnership grounded in trust, and tailored solutions that bring breakthrough therapies to patients."
Market Need and Clinical Advantages
By 2030, approximately 30 million patients in the U.S., Europe and Japan are expected to receive FXa DOACs as chronic anticoagulation therapy, including stroke prevention in atrial fibrillation (search) and prevention of deep vein thrombosis (search). Each week, more than 30,000 of these patients experience severe life-threatening bleeding (search) or require emergency surgery, where bleeding risk poses a critical challenge.
VMX-C001 has been developed with several clinical advantages, including universal dosing regardless of the specific FXa DOAC used, rapid and easy administration, compatibility with common anticoagulants like heparin, and no additional thrombotic risk. These features position VMX-C001 as a potential new treatment option for the substantial number of patients on FXa DOACs who need emergency surgery.
Company Background
VarmX (search) is a spin-off from Leiden University Medical Center founded in 2016 by Professor Pieter Reitsma, a leading expert in hemostasis and thrombosis. The company is supported by investors including Sound Bioventures, EIC, EQT Life Sciences, Inkef, Lundbeckfonden BioCapital, Ysios Capital, BioGeneration Ventures, InnovationQuarter, and CSL (search).
Rentschler Biopharma (search) is a family-owned CDMO with approximately 1,400 employees, headquartered in Laupheim, Germany, with operations in Milford, Massachusetts. The company provides process development and manufacturing of biopharmaceuticals, along with consulting, project management and regulatory support services.