Vesper Bio ApS, a clinical-stage biotech focused on neurodegenerative and neuropsychiatric diseases, announced positive topline results from its Phase Ib/IIa SORT-IN-2 trial evaluating VES001 in people carrying progranulin gene (GRN) mutations linked to frontotemporal degeneration (FTD-GRN).
Key Findings
- >95% mean increase in progranulin levels in cerebrospinal fluid (CSF) compared to baseline
- Normalisation of progranulin levels, potentially preventing symptomatic FTD
- Favourable safety and tolerability during three months of daily dosing
- Supports advancement to Phase IIb/III clinical trials in FTD-GRN
Restoring a Vital Protein
Individuals with GRN mutations have roughly half the normal levels of progranulin, a protein essential for maintaining neuronal health. In the SORT-IN-2 trial, VES001 increased progranulin levels in both plasma and CSF in a dose-dependent manner, effectively restoring them to healthy levels.
“These results show that VES001 can normalise progranulin without disrupting other sortilin functions,” said Dr. Mads Kjolby, Co-Founder and Chief Medical Officer, Vesper Bio. “We believe it has the potential to slow or even halt disease progression in FTD-GRN.”
Jacob Falck Hansen, CEO of Vesper Bio, added:
“This is a major milestone for Vesper and the FTD community. The data validate our targeted approach and strengthen our confidence in advancing VES001 as the first potential treatment for FTD-GRN.”
About the Study
The open-label, single-arm study enrolled six asymptomatic participants in the Netherlands and the UK who carry GRN mutations known to cause very low progranulin levels.
- Dosing: Daily oral treatment — 28 days at a lower dose, followed by 56 days at a higher dose
- Safety: Only mild adverse events reported; no severe events or discontinuations
- Clinical sites:
- Erasmus University Medical Centre (Rotterdam, Netherlands)
- Leonard Wolfson Experimental Neurology Centre (University College London, UK)
Professor Jonathan Rohrer, Principal Investigator (UCL), noted:
“The ability to restore progranulin to normal levels in people who are years away from symptoms is remarkable — it opens the door to preventing FTD before it begins.”
What’s Next
The SORT-IN-2 study was supported by the Alzheimer’s Drug Discovery Foundation (ADDF) and the Association for Frontotemporal Degeneration (AFTD) through the TreatFTD program.
A full data release is expected in Q1 2026, after which Vesper Bio plans to begin Phase IIb/III trials in symptomatic patients to assess efficacy on clinical and biomarker outcomes.
About Vesper Bio
Vesper Bio is a global leader in sortilin receptor biology, developing small-molecule selective sortilin inhibitors as oral treatments for neurodegenerative and neuropsychiatric diseases. Its lead candidate, VES001, is designed to restore progranulin levels and reduce neuroinflammation in t , a genetic subtype of frontotemporal dementia.
