Alterity Therapeutics (NASDAQ:ATHE) outlined its development strategy for lead drug candidate ATH434, highlighting positive Phase II data in multiple system atrophy (MSA), planned regulatory interactions with the U.S. Food and Drug Administration (FDA), and preparations to move into a global Phase III program.
Company focus and the unmet need in MSA
In the presentation, the company emphasized that MSA is a rapidly progressive neurodegenerative disease that can resemble Parkinson’s disease early, but progresses more aggressively—described as more akin to ALS in its pace. Alterity said there are up to 50,000 patients in the U.S. with MSA and noted that more than 50% of patients require a wheelchair within five years of symptom onset, with survival typically 7–8 years after symptoms first appear.
Mechanism: targeting iron and alpha-synuclein
Alterity described ATH434 as an orally administered compound designed to cross the blood-brain barrier and penetrate cells, aiming to address disease processes occurring inside neurons. The company explained that in MSA and Parkinson’s disease, the protein alpha-synuclein can misfold and aggregate, forming clumps that impair neuronal function. It also said excess iron accumulates in brain regions involved in disease, contributing to alpha-synuclein aggregation and oxidative injury.
ATH434 is positioned as an “iron chaperone,” which Alterity said means it binds and redistributes excess iron within cells without removing iron from the body. By reducing reactive iron, the company said the drug is intended to lessen alpha-synuclein aggregation and oxidative injury, with a goal of preserving neurons and slowing decline. Alterity characterized ATH434 as potentially disease-modifying rather than symptomatic.
The company noted that ATH434 has orphan drug designation in the U.S. and the European Union and fast track designation with the FDA.
Phase II design and key efficacy findings
Alterity’s Phase II trial was described as a randomized, double-blind, placebo-controlled study enrolling 77 patients. Participants were assigned equally to 75 mg twice daily, 50 mg twice daily, or placebo. The company said patients met clinical criteria for MSA and that biomarkers were used to increase diagnostic specificity.
The trial’s key clinical endpoint was the modified UMSARS Part I, a functional component of the Unified Multiple System Atrophy Rating Scale (UMSARS), which assesses domains such as speech, swallowing, fine motor tasks, walking and falls, and symptoms related to orthostatic hypotension.
According to the company, placebo patients worsened by about 8 points over one year on the modified UMSARS Part I, while both ATH434 dose groups separated from placebo. Alterity reported:
- A statistically significant result at 50 mg twice daily, described as approximately 48% less decline than placebo.
- A 75 mg twice daily group described as about 30% less decline than placebo, which the company said was also clinically significant.
Alterity noted that the minimal clinically important difference on the endpoint is 1.5 points and said both dose groups exceeded that threshold. The company also discussed a baseline imbalance in severe orthostatic hypotension—about 29%–30% of patients in the high-dose group versus 4%–5% in the lower-dose groups—which it said can predict faster progression and affected interpretation of some clinical data. It added that correcting for this imbalance largely addressed differences between dose groups.
Secondary measures, safety, and imaging endpoints
On a patient-reported measure of orthostatic hypotension symptoms, Alterity said placebo patients worsened by about 6 points while both active dose groups stabilized on average. The company also highlighted results from a digital biomarker collected via a wearable pendant, reporting that placebo patients lost about 2,500 steps per day by one year, while active treatment groups lost about half that amount, with similar patterns in total walking time and other activity measures.
On safety, Alterity said it did not observe central nervous system adverse events associated with treatment and reported similar overall adverse event rates across placebo and active groups. It added there were no serious or severe adverse events related to study drug.
The company said the primary endpoint of the study was change in brain iron assessed by neuroimaging. It reported evidence of target engagement, including reduced iron accumulation in the pallidum and putamen, with more consistent effects reported in the 50 mg dose group. Alterity also presented trends toward less brain atrophy in treated groups using a tool piloted in the study, but said these findings were not statistically significant and the study was not powered to detect those differences.
Next steps: FDA meeting, Phase III planning, and publication
Alterity said it is preparing for FDA interactions and targeting an end-of-Phase II meeting around mid-year to discuss Phase III design, including population, endpoints, and dosing. Management said it expects to disclose the outcome of that meeting in the third quarter if the timing holds, and anticipated initiating Phase III about six months after receiving FDA feedback.
The company said Phase III is expected to be a global study, including Australia, the United States, and several European countries, and that a larger number of skilled centers will be needed due to challenges in identifying and recruiting MSA patients. Management also indicated the Phase III trial would not be much more than 200 patients, compared with roughly 75–80 in Phase II.
Alterity said the Phase II study results will be submitted for publication in a peer-reviewed journal and that publication is not required before FDA meetings. The company also discussed interest in expanding ATH434 into Parkinson’s disease and other conditions where iron accumulation is implicated, including Friedreich’s ataxia and progressive supranuclear palsy, while noting that additional resources and patent clarity would be considerations for broader development.
In closing remarks, management said success in MSA could be “transformative” for the company and could support expansion into larger indications such as Parkinson’s disease.
About Alterity Therapeutics (NASDAQ:ATHE)
Alterity Therapeutics is a clinical-stage biotechnology company focused on the development of novel treatments for neurological and neurodegenerative disorders. The company’s research portfolio centers on small molecules designed to target underlying disease mechanisms, with an emphasis on improving synaptic function and mitigating neuroinflammation.
Among its lead assets is trofinetide (NNZ-2566), a peptide analog derived from insulin-like growth factor 1, which is being investigated for the treatment of Rett syndrome and Fragile X syndrome in ongoing clinical trials.
