Open-Label Extension Study to Provide Access to ATH434 in Patients with Multiple System Atrophy

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Alterity Therapeutics Limited

Participant type

Patients

Age range

18-64 years, 65+ years

Gender

Male and Female

Therapeutic area

Diseases [C] - Nervous System Diseases [C10]

Decision date (initial)

2026-05-13

Transition trial

No

Low-intervention

No

Rare-disease indication

Yes

Vulnerable population

No

Funding sources

Alterity Therapeutics

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Therapy, Safety

To assess the long-term safety and tolerability of ATH434 in participants with MSA receiving open-label treatment in this extension study.

Conditions and MedDRA coding

Multiple System Atrophy

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 6

1. Completed the ATH434-201 study in accordance with the study protocol requirements.
2. Willing and able to provide written informed consent prior to any study-related procedure.
3. Able to attend scheduled study visits (clinic and remote) as specified in the Schedule of Events.
4. Expected, in the investigator’s judgement, to benefit from treatment with ATH434.
5. Female participants must meet one of the following criteria: • Postmenopausal (defined as ≥12 months of spontaneous amenorrhea with a serum follicle stimulating hormone [FSH] level consistent with postmenopausal status at screening, or • Surgically sterile (documented hysterectomy, bilateral oophorectomy, or bilateral salpingectomy performed ≥6 months prior to enrollment), or • Of childbearing potential and compliant with the contraception requirements described in Section 7.4.2.
6. Male participants must agree to comply with the contraception requirements described in Section 7.4.3.

Exclusion criteria 7

1. Discontinued prior ATH434-201 treatment for any reason.
2. Any medical condition or psychiatric condition that, in the opinion of the investigator, results in an unfavorable benefit–risk ratio with ATH434 treatment. This includes but is not limited to: • Hemoglobin (male <13 g/dL; female <11 g/dL); • Abnormal liver tests: ALT and/or AST > 3 × ULN or Total bilirubin > 1.5 x ULN; • Renal impairment: creatinine clearance < 50 mL/min, as estimated by the Cockcroft–Gault formula; • Other clinically relevant abnormalities considered significant by the Investigator.
3. History of certain neurological event or abnormalities.
4. Use of prohibited concomitant medications that can interfere with ATH434 metabolism. (See Section 7.1).
5. Known hypersensitivity to ATH434 or to any excipient in the formulation.
6. Pregnant or breastfeeding women or planning to become pregnant or breastfeeding while participating in the study.
7. Participated in an interventional medical research study/program within 30 days or 5 drug half-lives, whichever is longer, at the time of enrollment, or planning to do so while participating in the study.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Assessment of long term safety and tolerability based on incidence and severity of AEs and SAEs, changes in laboratory and vital sign parameters including orthostatic measures, exposure to ATH434, treatment discontinuations due to adverse events, and deaths.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Alterity Therapeutics Limited

Sponsor organisation

Alterity Therapeutics Limited

Address

Suite 4 Level 14, 350 Collins Street 350 Collins Street

City

Melbourne

Postcode

3000

Country

Australia

Scientific contact point

Organisation

Alterity Therapeutics Limited

Contact name

David Stamler, MD

Public contact point

Organisation

Alterity Therapeutics Limited

Contact name

Alterity Clinical Trials

Third parties 1

Locations

1 EU/EEA country · 4 investigational sites

By country

Investigational sites

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 7 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

1 submissions — initial application plus substantial / non-substantial modifications