CSL Partners With VarmX in a Strategic Collaboration and Option Agreement to Develop First-in-Class Investigational Coagulation Treatment
CSL Press Release
Melbourne, Australia – 16 September 2025 – CSL today announced it has entered into a strategic collaboration with privately held Dutch biotech company VarmX BV to support the company’s development of VMX-C001. CSL has also entered into an agreement with VarmX shareholders granting CSL an exclusive option to acquire all issued and outstanding shares of the company. VMX-C001 is a novel treatment to help restore blood coagulation in patients requiring urgent surgery or experiencing severe bleeding while on Factor Xa direct oral anticoagulants (FXa DOACs).
VMX-C001 is an investigational, recombinant modified Factor X protein administered as a rapid single-dose, intended to bypass the FXa anticoagulation activity and restore coagulation in patients on Factor Xa inhibitors. It offers the potential to be used with all FXa DOACs and can be administered with other common anticoagulants like heparin, and potentially, with no additional thrombotic risk.
“We are excited to partner with VarmX to develop a new treatment and address a significant unmet need aligning strongly with our strategic ambition to deliver enduring patient impact,” said CSL’s Chief Executive Officer Dr. Paul McKenzie. "It also aligns with our portfolio of medicines designed to minimize bleeding, preserve a patient’s own blood supply, improve surgical and medical outcomes and support global public health approaches to patient blood management."
VarmX’s medicine fits within CSL’s core therapeutic areas, said CSL Executive Vice President and Head of Research & Development Bill Mezzanotte.
“VMX-C001 is right in our sweet spot – within the field of hematology and bleeding disorders. It also fits with our strategy of seeking more external partners to accelerate our clinical and commercial pipeline through investments in validated, clinical-stage opportunities.
“CSL was particularly interested in VMX-C001's unique mechanism of action and the preclinical and early clinical data, which led to the U.S. Food and Drug Administration (FDA) granting Fast Track Designation; recognising VMX-C001's potential to address a critical unmet medical need.”
Under the terms of the strategic collaboration agreement, CSL will fund VarmX’s global Phase 3 trial evaluating VMX-C001 in patients taking FXa DOACs who require urgent surgery (EquilibriX-S). CSL will also fund and support VarmX in late-stage product development, manufacturing and pre-launch commercial and medical affairs activities.
CSL will make an upfront payment to VarmX of US$117 million for an exclusive option to acquire the company. CSL will have the right to exercise the option upon receipt of Phase 3 data. Subject to the exercise of the option and certain milestones and regulatory clearances being reached, VarmX will receive payments of up to US$388 million up to the launch of VMX-C001, plus further commercial milestones thereafter.
Commercial launch is anticipated in 2029.
“The collaboration with CSL represents a transformative step for VarmX”, said John Glasspool, Chief Executive Officer of VarmX. “By securing 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.”
More than 20 million patients globally take FXa DOACs as a chronic anticoagulation therapy, including stroke prevention in atrial fibrillation and deep vein thrombosis. About 3 per cent of these patients experience severe bleeding or require urgent surgery.
“Despite the unmet clinical need, no fully approved therapeutic agent is currently available in the E.U. or the U.S. for treating acute major bleeding in patients on Factor Xa inhibitors,” Mezzanotte said.
