Highlights

  • SNT-4728 showed a statistically significant difference in MDS-UPDRS Part III motor scores at Week 24 (p=0.021).
  • Participants on SNT-4728 showed improved or stabilised motor function, while the placebo group continued to decline.
  • No treatment-related serious adverse events were reported.
  • Primary endpoint results showed a significant reduction in brain inflammation in the putamen.

Syntara Limited (ASX:SNT) announced on 7 October 2026 secondary clinical endpoint results from its Phase 2 study of SNT-4728 in people with isolated REM Sleep Behaviour Disorder (iRBD). The results show a significant improvement in motor signs compared with placebo.

Study Design

The randomised, double-blind, placebo-controlled study enrolled 41 participants with iRBD, randomised 3:1 to SNT-4728 or placebo. Treatment lasted 12 weeks and was followed by a 12-week follow-up period.

The study was funded by Parkinson's Research Ventures in collaboration with Parkinson's UK, with clinical sites in Sydney and Oxford. SNT-4728 is an SSAO/MAO-B inhibitor targeting neuroinflammation in neurodegenerative diseases.

Primary and Secondary Endpoint Results

Primary endpoint results, reported on 6 July 2026, showed a statistically significant reduction in brain inflammation in the putamen (p=0.0145), with 20 of 30 participants on active treatment showing a reduction from baseline.

The secondary endpoint showed a statistically significant difference in the MDS-UPDRS Part III motor assessment at Week 24 (p=0.021). The SNT-4728 group showed improved or stabilised motor function during and after treatment, while the placebo group continued to deteriorate. Smartphone-based motor scores were directionally consistent with clinician assessments.

Safety and Commentary

No treatment-related serious adverse events were reported, and all adverse events were mild or moderate.

Principal Investigator Professor Simon Lewis said the study provides convergent exploratory evidence of biological activity in people with iRBD, together with an improvement in motor function maintained after treatment ceased. CEO Gary Phillips said there remains a large unmet need for drugs that go beyond symptomatic control, and described the convergence of biological and clinical outcomes as very encouraging.

Key Takeaways

  • SNT-4728 achieved a significant difference in clinician-assessed motor scores at Week 24.
  • Motor benefits were maintained after treatment ended, while placebo patients continued to decline.
  • The primary endpoint showed reduced brain inflammation in the putamen.
  • The safety profile showed no treatment-related serious adverse events.