CSL has released landmark five-year clinical results for its gene therapy HEMGENIX, confirming long-term durability, safety, and substantial clinical benefit for adults living with haemophilia B.
The findings, published in the New England Journal of Medicine and presented at the American Society of Hematology (ASH) Annual Meeting, reinforce the therapy’s potential to transform care for a rare bleeding disorder, which has long been managed with lifelong prophylactic infusions.
Yet the release comes at a critical moment in Australia, where the Medical Services Advisory Committee (MSAC) has recently issued a recommendation on HEMGENIX, and CSL has indicated it is unlikely to accept it.
HEMGENIX, the world’s first approved gene therapy for haemophilia B, continued to show strong, sustained outcomes five years after a single infusion. According to the latest HOPE-B study results, 94 per cent of patients remained free of continuous prophylaxis, eliminating the need for regular infusions, mean factor IX activity levels remained stable at 36.1 per cent at year five, annualised bleeding rates fell by around 90 per cent compared to pre-treatment, with similar reductions in joint and spontaneous bleeds, and no treatment-related serious adverse events were reported, and overall tolerability remained favourable.
Although the five-year data mark the final analysis for the HOPE-B study, participants who consent will continue to be monitored in the IX-TEND 222-3003 extended follow-up study, which will track patients for up to 15 years post-treatment.
“These five-year HOPE-B results mark a pivotal milestone for gene therapy,” said Professor Steven Pipe of the University of Michigan. “For those who have relied on frequent prophylactic infusions, achieving lasting bleed control from a single treatment offers the potential for greater day-to-day freedom and a life less burdened by the demands of ongoing therapy.”
CSL’s Senior Vice President and Head of Medical Affairs, Dr Deborah Long, said the data reinforce the company’s commitment to expanding access. “We are incredibly proud to share the five-year results from the HOPE-B study, which reinforce the lasting impact of HEMGENIX as a one-time treatment option for adults with hemophilia B,” she said. “These results highlight the meaningful difference HEMGENIX can make—helping people experience fewer bleeds compared to prophylaxis treatment and freeing them from the burden of regular ongoing treatment. We remain committed to expanding access to this important treatment.”
Despite global momentum, more than 75 people worldwide have now received HEMGENIX outside clinical trials, the therapy faces a challenging path to funded access in Australia.
MSAC recently issued a recommendation relating to the therapy’s reimbursement. CSL, has argued that it does not adequately reflect the value demonstrated by long-term evidence, the clinical needs of patients, or global standards of access.
HEMGENIX offers a one-time treatment designed to enable the body to continuously produce factor IX, removing the need for ongoing infusions that have defined haemophilia B care for decades. The therapy has been approved by regulators in the United States, Europe, Canada, the UK, Australia and several Asian markets.
>While MSAC’s recommendation has not progressed, the company’s release of positive five-year data could play a critical role in future deliberations.