Release Details
Denali Therapeutics Announces Primary Analysis and Long-Term Follow-Up of Phase 1/2 Study in Hunter Syndrome (MPS II) with Tividenofusp Alfa
- Long-term data demonstrate that robust reductions and normalization in key biomarkers from baseline were maintained over time with continued improvement in hearing, cognition and adaptive behavior
- Long-term safety data with median follow-up of two years, and out to more than four years, demonstrate that tividenofusp alfa was generally well tolerated
- Regulatory submission for accelerated approval is planned for early 2025;
U.S. launch preparation is ongoing to deliver tividenofusp alfa to families with MPS II in late 2025 or early 2026
“Longer-term clinical data add to confidence that normalization of key biomarkers endures over time and that treatment with tividenofusp alfa is associated with continued improvement in hearing, cognition and behavior, which is meaningful to affected individuals and their families,” said
“Our primary analysis in 47 participants with MPS II and the additional long-term data in up to more than four years, support the potential of tividenofusp alfa to address neurocognitive, behavioral, and physical effects for all individuals living with MPS II. We are working as fast as possible to enable tividenofusp alfa as a treatment option for individuals living with MPS II and enable access for them and their families,” said
The additional Phase 1/2 long-term data demonstrated that treatment with tividenofusp alfa led to substantial and significant reductions to normal and near-normal levels in central nervous system and peripheral biomarkers of disease, including cerebrospinal fluid (CSF) and urine heparan sulfate, and neurofilament light (NfL), a well-established marker of neurodegeneration. Clinical outcomes included normal liver volume after 24 weeks, hearing threshold improvement in all tested frequencies, and skill gains in most participants on measures of adaptive behavior and cognition. Administration of tividenofusp alfa was generally well tolerated in study participants. Most treatment-related adverse events (TEAEs) were mild or moderate, including infusion-related reactions (IRRs), anemia, vomiting, pyrexia, respiratory infections, and rash. Serious TEAEs in three participants (6.4%) were manageable, with resolution or stabilization with continued treatment. One participant discontinued treatment for reasons related to a moderate IRR and other non-treatment-related adverse events.
Denali also supported additional research relating to Hunter syndrome (MPS II) at the WORLDSymposium™ conference. Research presented by
About Hunter Syndrome (MPS II)
Hunter syndrome (MPS II) is a rare genetic disease that affects over 2,000 individuals in commercially accessible geographies, primarily males, and leads to physical, cognitive, and behavioral symptoms. Hunter syndrome is caused by mutations in the iduronate-2-sulfatase (IDS) gene, which leads to a deficiency of the IDS enzyme. Symptoms often begin emerging around age two and include physical complications, including organ dysfunction, joint stiffness, hearing loss and impaired growth, and neurocognitive symptoms with impaired development. The disease is characterized by a buildup of glycosaminoglycans (GAGs) in lysosomes — the part of the cell that breaks down materials including GAGs. The current standard of care, enzyme replacement therapy, partially treats physical symptoms but does not cross the blood-brain barrier, and as a result, cognitive and behavioral symptoms experienced by the majority of individuals with Hunter syndrome are not addressed. Therapies that address the range of behavioral, cognitive, and physical manifestations of the disease are recognized as an unmet need for the Hunter syndrome community.1
About Tividenofusp Alfa and the Phase 2/3 COMPASS Study
Tividenofusp alfa (or DNL310) is composed of the iduronate 2-sulfatase (IDS) enzyme fused to Denali’s proprietary Enzyme TransportVehicle™ (ETV), uniquely designed to deliver IDS into the brain and the body, with the goal of addressing behavioral, cognitive, and physical symptoms of Hunter syndrome (MPS II). The
The Phase 2/3 COMPASS study is enrolling participants with MPS II in
Tividenofusp alfa is an investigational therapeutic candidate and has not been approved for use by any Health Authority.
About
Denali Therapeutics is a biopharmaceutical company developing a broad portfolio of product candidates engineered to cross the blood-brain barrier for neurodegenerative diseases and lysosomal storage diseases. Denali pursues new treatments by rigorously assessing genetically validated targets, engineering delivery across the blood-brain barrier and guiding development through biomarkers that demonstrate target and pathway engagement. Denali is based in
Cautionary Note Regarding Forward-Looking Statements
This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements expressed or implied in this press release include, but are not limited to, statements regarding plans, timelines, and expectations related to Denali's TransportVehicle™ (TV) platform and its therapeutic and commercial potential; plans, timelines, and expectations relating to DNL310, including enrollment in the ongoing global Phase 2/3 COMPASS study, the likelihood of global approvals, the timing of planned regulatory filings, and the timing, likelihood, and scope of regulatory approvals and commercial launch; plans, timelines, and expectations related to DNL126; and statements made by
References
- Muenzer, J., et al. Community consensus for Heparan sulfate as a biomarker to support accelerated approval in Neuronopathic Mucopolysaccharidoses. Mol Genet Metab. 2024 Aug;142(4):108535
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Source: Denali Therapeutics Inc.