CSL and uniQure: Delivering the World’s First Gene Therapy for Haemophilia B

Haemophilia B is a rare genetic bleeding disorder caused by a single gene mutation, resulting in insufficient production of factor IX, a protein essential for blood clotting.  Traditional therapies require frequent prophylactic infusions, imposing a burden on patients that can impact quality of life and increase the risk of complications. 

In 2020, CSL entered into a strategic partnership with uniQure, a biotechnology company with expertise in gene therapy research and development. The collaboration centred on HEMGENIX® (etranacogene dezaparvovec) – a one-time gene therapy for adults with haemophilia B. 

“The partnership brought together two organizations with complementary strengths: uniQure’s experience in adeno-associated virus (AAV)-based gene therapy development and CSL’s global capabilities in rare disease development, hemophilia, regulatory engagement, market access, funding pathways, and international commercialization,” said Andres Brainsky, CSL Vice President R&D Hematology. 

From research to global readiness

Prior to the partnership, uniQure had advanced the therapy through clinical development. Under the collaboration agreement, uniQure completed its Phase III clinical trial and took initial responsibility for commercial manufacturing, while CSL took responsibility for global regulatory submissions, market access and commercialization. This approach preserved the scientific continuity while enabling the transition from clinical research to global regulatory interaction and funding pathways – particularly complex for advanced therapies such as gene therapy.

For CSL, the collaboration aligned with its long-standing focus on rare and serious diseases, including haemophilia, and its experience working with regulators and health systems in multiple jurisdictions.

Navigating complex regulatory and funding pathways

Gene therapies present distinct considerations for regulators, given their novel mechanisms, one-time administration, and the need for long-term safety and efficacy monitoring.  Hemgenix received regulatory approvals in major markets, including from the US Food and Drug Administration (FDA) in 2022 and from the European Commission in 2023, following evaluation by independent regulatory authorities.

CSL’s role in this focused on working with regional regulators and health authorities, completing phase 3, to complete five years of follow up for each patient treated. CSL also supported local submission requirements, ensuring readiness to meet post-authorisation obligations, including conducting a trial in adolescent patients, which is currently ongoing. These activities required close coordination with uniQure, as well as ongoing dialogue with regulators as evidence continues to be collected overtime.

For gene therapies, regulatory approval is only one hurdle.  Unlike traditional chronic treatments, gene therapies raise new questions for healthcare systems about value assessment, funding models, and long-term outcomes, with medical teams heavily involved in supporting the preparation before each commercial dose.

Hemgenix is administered once, yet its  potential efficacy is  intended to last for many years. This challenges conventional reimbursement approaches that are typically built around recurring treatments and annual budgets. As a result, payers and health systems have explored alternative funding and payment models, including outcome-based agreements, staged payments, and other mechanisms designed to align the cost with long-term benefit.

As part of the partnership, CSL has worked with health authorities, payers and treatment centres to support these discussions, recognising that access to gene therapies depends on collaboration across the entire healthcare ecosystem. These efforts are tailored to each country’s healthcare structure and policy environment, and this work has received external international recognition through the Prix Galien award. Hemgenix has since become the first therapy funded via the UK’s Innovative Medicines Fund and is funded in Germany, Denmark, Spain, Austria and Italy.

“For biotech companies seeking to develop and commercialise their research, CSL offers more than resources. We bring deep therapeutic expertise, global infrastructure, and a genuine commitment to partnership. CSL’s successful collaboration with uniQure demonstrates our capability to advance ground-breaking science, making a real difference for patients worldwide,” said Bill Mezzanotte, CSL Executive Vice President and Head of Research & Development.

By aligning expertise across development, regulation, commercialization and access, CSL and uniQure’s collaboration offers a case study in how the next generation of therapies can be introduced responsibly – with careful consideration of the systems that ultimately determine whether innovation reaches patients.

Read more about the partnership here:https://www.uniqure.com/programs-pipeline/hemophilia