TA-ERT Profoundly and Durably Lowered Cerebral Spinal Fluid Heparan Sulfate Non-Reducing End (CSF HS-NRE), the Factor Responsible for Neurodegeneration in MPS IIIB
U.S. FDA Confirmed that CSF HS-NRE is a Surrogate Biomarker Reasonably Likely to Predict Clinical Benefit and Could Serve as Basis for Accelerated Approval
Cognition and Cortical Grey Matter Volume Were Stabilized in Patients Treated with TA-ERT Relative to Declines Observed in Untreated Patients
SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)-- Spruce Biosciences, Inc. (OTCQB: SPRB), a late-stage biopharmaceutical company focused on developing and commercializing novel therapies for neurological disorders with significant unmet medical need, today announced results from a long-term data integration of tralesinidase alfa enzyme replacement therapy (TA-ERT) clinical program in patients with Sanfilippo Syndrome Type B (MPS IIIB).
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Figure 1. TA-ERT Therapy Leads to Profound and Durable Reduction in CSF HS-NRE Over a 5-Year Period. Dashed line represents upper limit of normal (10 ng/mL) for CSF HS-NRE; LS = least squares; LS mean ±SE based on mixed-model repeated measures (MMRM) analysis with study visit as covariate. Note: CSF HS-NRE levels were averaged over each 0.5-year interval.
Spruce integrated and evaluated group-level efficacy data for cerebral spinal fluid heparan-sulfate non-reducing end (CSF HS-NRE), cortical grey matter volume (CGMV), and Bayley-III Cognitive Raw Score (BSID-C), the cognitive subscale of the Bayley Scales of Infant and Toddler Development - Third Edition (Bayley-III), as well as safety data over a five-year period from clinical studies 201, 202, and 401. Data from treated patients (n=22) in the studies 201, 202, and 401 was compared with data from untreated patients with MPS IIIB in natural history studies 901 and 902.
“These data demonstrate a rapid, profound, and durable effect of ICV-administered TA-ERT on normalizing CSF HS-NRE, the pathogenic factor leading to neurodegeneration, and in stabilizing CGMV and cognitive function, relative to the declines observed in untreated children with Sanfilippo Syndrome Type B (MPS IIIB) in the natural history studies,” said Paul Harmatz, M.D., Principal Investigator in studies 901, 201, and 202 and Professor in Residence, Department of Pediatrics, University of California, San Francisco (UCSF) and UCSF Benioff Children’s Hospital Oakland. “This is an important development toward relief for children and families whose lives are impacted by this devastating condition.”
“Convincing positive outcomes have been experienced by families who resoundingly state that the benefits of TA-ERT outweigh risks in their real-world experiences,” said Cara O’Neill, M.D., FAAP, Co-Founder and Chief Science Officer of Cure Sanfilippo Foundation. “Biomarker data, along with promising clinical outcomes, are significant and meaningful from the perspective of the patient community. Currently, there is no U.S. FDA-approved therapy for the treatment of MPS IIIB, and disease management consists of limited palliative care. We are eager to see TA-ERT advance under the accelerated approval pathway.”
Cerebral Spinal Fluid Heparan-Sulfate Non-Reducing End (CSF HS-NRE)
Integrated group-level data from clinical studies 201, 202, and 401 demonstrate that TA-ERT therapy significantly reduced to normal or near normal CSF HS-NRE levels over a five-year period (Figure 1). At 240 weeks, CSF HS-NRE decreased 91.5 ng/mL from baseline (95% CI: -102.10, -80.90; p