Multiple System AtrophyPhase 2NCT07729852
Open-Label Access to ATH434 for Patients Who Completed Study ATH434-201 in France
A Phase 2 study testing ATH434 in people with Multiple System Atrophy, run by Alterity Therapeutics at 4 sites in France.
Trial summary
This multicenter open-label extension study conducted in France is designed to provide ATH434 orally BID to eligible patients who completed the Phase 2 study ATH434-201, and who may benefit from this treatment according to the evaluation by the Investigator. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Multiple System Atrophy
- What is being tested?
- ATH434
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 7 participants
- Where
- 4 sitesFrance
- Study dates
- 1 Oct 2026to Jul 2029
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Who may be able to join
- Completed Alterity protocol ATH434-201.
- Expected to benefit from treatment from treatment with ATH434, in the opinion of the Investigator.
Who cannot join
- Discontinued prior ATH434 treatment (ATH434-201) for any reason.
- Significant medical or psychiatric condition that may decrease the benefit-risk ratio of participation in this program to an unacceptable level, as per the Investigator's opinion.
Trial locations and contacts
4 sites in 1 country. Contact the study team or a site near you to ask about taking part.
France4 sites
Centre Hospitalier Universitaire de Bordeaux
Bordeaux, New Aquitaine, 33076
Hôpital de la Timone
Marseille, Provence-Alpes-Côte d'Azur Region, 13005
Hôpital Universitaire Pitié Salpêtrière
Paris, Île-de-France Region, 75013
Hôpital Pierre-Paul Riquet
Toulouse, Midi-Pyrenees, 31300
About this study
Official title: Open-Label Extension Study to Provide Access to ATH434 in Patients With Multiple System Atrophy
This multicenter open-label extension study conducted in France is designed to provide ATH434 orally BID to eligible patients who completed the Phase 2 study ATH434-201, and who may benefit from this treatment according to the evaluation by the Investigator.
Read the detailed description
This is a multicenter, open-label extension (OLE) study designed to provide continued access to the investigational product ATH434 for eligible participants with Multiple System Atrophy (MSA) who have successfully completed the prior Phase 2 clinical trial (ATH434-201) in France. Up to 5 participants will be enrolled. No new participants will be recruited or enrolled in this study.
The primary objective is to monitor long-term safety, tolerability, and clinical response. Eligible participants will receive ATH434 at a dose of 75 mg twice daily (BID) to be taken with food.
The study is divided into two operational phases:
Initial Treatment Phase: Participants will receive treatment for a planned duration of 12 months.
Extension Phase: Participants may continue treatment beyond the initial 12 months based on the investigator's clinical judgment of ongoing benefit, safety, and tolerability. Continued eligibility will be re-evaluated and documented every 3 months.
Participants will undergo a combination of in-clinic and remote visits to perform safety monitoring, clinical evaluations, and investigational product accountability.
- Conditions
- Multiple System Atrophy
- Being tested
- ATH434
- Medical subject headings
- Multiple System Atrophy
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ATH434Drug
Also called PBT434
ATH434 75 mg tablets administered orally twice daily (BID).
| Study group | Role | What they receive |
|---|---|---|
| ATH434 75mg BID | Experimental | Participants who completed the prior ATH434-201 Phase 2 trial will receive ATH434 75 mg orally twice daily (BID). Treatment consists of an initial 12-month treatment phase, followed by an ongoing extension phase based on investigator assessment of continued clinical benefit, safety, and tolerability Receives: Drug: ATH434 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence, Severity, and Relationship of Adverse Events (AEs) and Serious Adverse Events (SAEs)
All AEs will be reviewed at every participant contact and documented in the CRF. All SAEs will be reported within 24 hours of awareness in accordance with local regulatory requirements.
Measured: Baseline to completion of study treatment, an average of 1 year.
Change From Baseline in Clinical Laboratory Parameters
Clinical laboratory parameters include hematology and blood chemistry panels.
Measured: Baseline to completion of study treatment, an average of 1 year.
Change From Baseline in Vital Signs
Vital signs include blood pressure, pulse, temperature, and respiration rate.
Measured: Baseline to completion of study treatment, an average of 1 year.
Duration of Exposure to ATH434
Total duration of treatment with investigational product per participant.
Measured: Baseline to completion of study treatment, an average of 1 year.
Cumulative Dose of ATH434
Total cumulative dose of investigational product administered per participant.
Measured: Baseline to completion of study treatment, an average of 1 year.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted28 Jul 2026
- Study start1 Oct 2026
- Primary completionJul 2029 (estimated)
- Study completionJul 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Multiple System AtrophyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 7 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Alterity Therapeutics
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07729852
- Sponsor's protocol ID
- ATH434-203
- Other IDs
- 2025-524317-88-00, 2025
- Status last verified
- Oct 2026
- First submitted
- 16 Jul 2026
- Last updated
- 9 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No