Alterity presents new Phase 2 analyses of ATH434 in MSA at MDS Congress

Alterity Therapeutics announced on October 5, 2026 that additional analyses from its Phase 2 "ATH434-201" trial in Multiple System Atrophy (MSA) were presented at the 2026 International Congress of Parkinson's Disease and Movement Disorders in Seoul, Korea. The poster combined clinical, biomarker, and imaging findings from the trial after controlling for baseline disease severity as measured by cerebrospinal spinal fluid neurofilament light chain, or CSF NfL.¹

The analysis found that higher baseline CSF NfL predicted greater decline at Week 52, with each 1,000 pg/mL increase associated with about 0.9 additional points of worsening on UMSARS Part I, a statistically significant result (p=0.033).¹

Using a mixed model for repeated measures applied to the modified intent-to-treat population of 61 patients, ATH434 50 mg showed a statistically significant slowing of functional decline on the 11-item UMSARS Part I at Week 52, with a 4.64-point difference versus placebo, equivalent to roughly a 52% slowing of decline and about three times the 1.5-point threshold considered a minimal clinically important difference (p=0.032).¹ The 75 mg dose showed a 2.81-point difference versus placebo at Week 26 (p=0.072) and Week 52 (p=0.179).¹

On imaging, the study's main imaging goal of showing a change in substantia nigra iron levels at Week 52 was not achieved, though iron levels trended lower in the putamen and globus pallidus with ATH434 compared to placebo.¹ In the dentate nucleus, iron signal rose relative to placebo at Week 52 for the 50 mg dose (+0.016 ppm, p=0.021), which the company said may reflect mobilized iron moving through the brain's glymphatic system.¹

The company said ATH434 was well tolerated, with adverse event rates similar to placebo and no serious adverse events attributed to the drug.¹ Alterity said it is preparing to begin a Phase 3 pivotal trial in MSA.¹