Leiden-based VarmX, a biotechnology company specialising in therapies for coagulation disorders, announced a strategic collaboration with Australian biotechnology firm CSL to advance the development of its lead product — VMX-C001.

John Glasspool, Chief Executive Officer of VarmX, says, “The collaboration with CSL represents a transformative step for VarmX. By securing full funding for the registrational trial, product development, CMC and pre-launch activities, we are well-positioned to bring VMX-C001 to patients. We are proud to partner with CSL, whose expertise and global reach will be invaluable as we move forward.”

VMX-C001 is a novel treatment designed to restore blood clotting in patients requiring urgent surgery or experiencing severe bleeding while on Factor Xa (FXa) direct oral anticoagulants (DOACs).

CSL announces option arrangement with VarmX

As a part of the collaboration, Melbourne-based CSL has also entered into an exclusive option arrangement with VarmX shareholders to acquire all issued and outstanding shares of the company.

Under the terms of the strategic collaboration agreement, CSL will fully fund VarmX’s global Phase 3 EquilibriX-S trial to evaluate VMX-C001 for patients on FXa DOACs who need urgent surgery.

CSL will also support VarmX in product development, manufacturing, and pre-launch activities.

CSL will pay VarmX shareholders $117M (approximately €99M) upfront when the deal closes for the exclusive option to buy the company.

They can exercise this option based on the results of Phase 3 data.

If certain conditions are met and after regulatory approvals, VarmX shareholders will get an extra $388M  (approximately €328.4M)  as part of the acquisition.

They may also receive additional payments leading up to the launch of VMX-C001 and up to $1.7B (approximately €1.43B) based on sales success afterwards.

VarmX: Specialising in hemostasis and thrombosis therapies

VarmX is a spin-off from the Leiden University Medical Centre (LUMC), founded in 2016 by Professor Pieter Reitsma, an expert in hemostasis and thrombosis.

VarmX’s lead compound VMX-C001 is a modified recombinant blood factor X.

The compound is being developed for the treatment of severe spontaneous bleeding and for the prevention of bleeding during urgent surgery in patients taking oral factor Xa inhibitors (FXa DOACs) as anticoagulation therapy.

It could offer the potential to be used with all FXa DOACs and be administered with other common anticoagulants like heparin, and potentially, with no additional thrombotic risk.

By 2030, around 30 million patients in the US, Europe, and Japan will be using Factor Xa (FXa) direct oral anticoagulants (DOACs) for conditions like preventing strokes in atrial fibrillation and treating deep vein thrombosis.

While these medications are effective, 2-4 per cent of patients each year experience serious bleeding or need emergency surgery. 

This means over 30,000 patients are affected every week.

VMX-C001 recently received Fast Track Designation from the FDA on September 3, 2025.

This designation highlights its potential to help patients on FXa DOACs who need urgent surgical intervention. A commercial launch is expected in 2029.

John Glasspool, Chief Executive Officer of VarmX, concludes, “We are grateful for the continued support of our investors, including Sound Bioventures, EIC, EQT Life Sciences, INKEF, Lundbeckfonden BioCapital, Ysios Capital, BioGeneration Ventures, InnovationQuarter, LEH and UNIIQ, who share our vision of transforming urgent care for patients and have been instrumental in helping the company grow and reach this milestone.”

CSL: Featuring a portfolio of lifesaving medicines

CSL is a global biotechnology company with a dynamic portfolio of lifesaving medicines, including those that treat haemophilia and immune deficiencies, vaccines to prevent influenza, and therapies for iron deficiency and nephrology.

CSL currently operates three divisions: CSL Behring, CSL Seqirus, and CSL Vifor. These divisions provide lifesaving products to patients in over 100 countries and employ 32,000 people.

Dr. Paul McKenzie, Chief Executive Officer of CSL, comments, “We are excited to partner with VarmX to develop a novel treatment and address a significant unmet need, aligning strongly with our strategic ambition to deliver enduring patient impact. It also aligns with our portfolio of medicines designed to minimise bleeding, preserve a patient’s own blood supply, improve surgical and medical outcomes and support global public health approaches to patient blood management.”