Trial Review

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
Help: Registration number
ACTRN12626001173381
Ethics application status
Help: Ethics application status
Approved
Date submitted
Help: Date submitted
14/08/2026
Date registered
Help: Date registered
21/09/2026
Date last updated
Help: Date last updated
21/09/2026
Date data sharing statement initially provided
Help: Data sharing statement date
21/09/2026
Type of registration
Help: Type of registration
Retrospectively registered

Titles & IDs
Public title
A Phase 1, 2-Part, Adaptive Design, Drug-Drug Interaction Study to Assess the Effect of Acid Reducing Agents on the Pharmacokinetics of ATH434 in Healthy Subjects
Scientific title
A Phase 1, 2-Part, Adaptive Design, Drug-Drug Interaction Study to Assess the Effect of Acid Reducing Agents on the Pharmacokinetics of ATH434 in Healthy Subjects
Additional trial identifiers [1] 316372 0
ATH434-104 Part 2
Universal Trial Number (UTN)
Trial acronym
Related trial records
ACTRN12626000320358 is Part 1 of this two-part protocol. If esomeprazole in Part 1 is determined to affect the PK of ATH434, Part 2 of the study will be conducted.

Health condition
Health condition(s) studied:
Multiple System Atrophy (MSA) 340457 0
Condition category
Condition code
Neurological 336666 336666 0 0
Neurodegenerative diseases

Intervention/exposure
Study type
Interventional
Description of the intervention or exposure
Period 1 (Day 1): Participants will receive a single oral dose of 75mg ATH434 tablet
Intervention: In Period 2 (Day7) participants will receive a single dose of 20mg Famotidine with a single dose of 75mg ATH434. Subjects will be dosed while seated, followed by hand and mouth checks to ensure that study drug has been swallowed by the subject. This is an adaptive trial, the timing of famotidine dosing in Period 2 may be altered based on emerging data from Part 1 (ACTRN12626000320358). There will be a 6-day washout between each of the two ATH434 doses. The proposed famotidine dose timing for Period 2 is either 10 hours before ATH434 dosing or 2 hours after.
Intervention code [1] 334211 0
Treatment: Drugs
Description of the comparator or control
Period 1 (Day 1) is the control period. In Period 1, participants will receive a single oral dose of ATH434 75mg tablet on Day 1
Control group
Active

Outcomes
Primary outcome [1] 345569 0
Single-dose primary PK parameters for ATH434 administered with and without famotidine: Area under the concentration-time curve from time 0 to the last measurable concentration (AUC0-t), Area under the concentration-time curve extrapolated to infinity (AUCinf), and Maximum observed drug concentration (Cmax)
Timepoint [1] 345569 0
Blood samples will be collected at following timepoints on days 1 and 7: • Predose (within 2 hours prior to dosing) • Post Dose: 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2. 2.5, 3.5, 4, 6, 10, 16, 24, 32, and 48 hours
Secondary outcome [1] 462188 0
Additional pharmacokinetic parameters of ATH434, including time of maximum drug concentration (tmax), time lag (tlag), apparent elimination half-life (t½), apparent oral clearance (CL/F), and apparent volume of distribution (Vz/F).
Timepoint [1] 462188 0
Blood samples will be collected at following timepoints on days 1 and 7: • Predose (within 2 hours prior to dosing) • Post Dose: 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2. 2.5, 3.5, 4, 6, 10, 16, 24, 32, and 48 hours
Secondary outcome [2] 462189 0
Safety and tolerability as measured by incidence of Treatment-Emergent Adverse Events (TEAEs)
Timepoint [2] 462189 0
AEs will be monitored from daily from check-in (Day -1) through the End of Study (Day 14).
Secondary outcome [3] 462190 0
Safety and tolerability as measured by vital sign parameters
Timepoint [3] 462190 0
Measured at screening, check-in (Day -1), Day 1, Day 7 and Day 9
Secondary outcome [4] 462191 0
Safety and tolerability as measured by clinical laboratory tests
Timepoint [4] 462191 0
Measured at screening, check-in (Day -1), Day 2, Day 8. An additional assessment will be performed on Day 9 if clinically significant abnormalities are detected at Day 8.
Secondary outcome [5] 462193 0
Safety and tolerability as measured by physical examination
Timepoint [5] 462193 0
A complete physical examination will be performed at Screening. An abbreviated physical examination will be performed at check-in (Day -1), Day 1 and Day 9.
Secondary outcome [6] 462194 0
Safety and tolerability as measured by 12-lead electrocardiogram
Timepoint [6] 462194 0
ECGs will be performed at Screening, check-in (Day -1) and Day 9
Secondary outcome [7] 462195 0
Safety and tolerability as measured by the Columbia-Suicide Severity Rating Scale (C-SSRS)
Timepoint [7] 462195 0
The C-SSRS Screening/Baseline will be used at Screening The C-SSRS Since Last Visit will be used at check-in (Day -1) and Day 9

Eligibility
Key inclusion criteria
Demographics: Male or female aged 18 to 55
Health Status: - Good general health (normal physical, ECG, and labs).
BMI: Between 18 and 32 kg/m².
Contraception:
- Women must be postmenopausal, surgically sterile, or using double contraception. - Men must use condoms or have a sterile partner (vasectomy/postmenopausal)
Lifestyle: Willing to eat standardized meals and abstain from caffeine (48 hours pre-dose until discharge). Veins: Good venous access for blood draws.
Minimum age
18 Years
Maximum age
55 Years
Sex
Both males and females
Healthy volunteers
Yes
Key exclusion criteria
Medical History:
- No significant history of heart, liver, kidney, GI, or neurologic disease.
- No conditions or surgeries that affect drug absorption (e.g., gastric bypass, chronic diarrhea).
- No history of significant drug allergies.
Prohibited Substances:
- Nicotine: No tobacco/nicotine use in the last 3 months.
- Alcohol: No regular heavy drinking or recent history of abuse.
- Drugs: No recreational drug use.
Medications:
- No prescription/OTC meds or supplements (including vitamins/herbal) for 14 days prior to dosing. - No enzyme inhibitors/inducers (e.g., St. John's Wort) for 30 days prior.
Pregnancy: Women cannot be pregnant or breastfeeding.

Study design
Purpose of the study
Treatment
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Crossover
Other design features
Phase
Phase 1
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
4/06/2026
Date of last participant enrolment
Anticipated
Actual
16/06/2026
Date of last data collection
Anticipated
Actual
29/06/2026
Sample size
Target
12
Accrual to date
Final
12
Recruitment in Australia
Recruitment state(s)
SA
Recruitment postcode(s) [1] 45875 0
5000 - Adelaide

Funding & Sponsors
Funding source category [1] 320982 0
Commercial sector/Industry
Name [1] 320982 0
Alterity Therapeutics Limited
Country [1] 320982 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
Alterity Therapeutics Limited
Address
Country
Australia
Secondary sponsor category [1] 324871 0
None
Name [1] 324871 0
Address [1] 324871 0
Country [1] 324871 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 319515 0
Bellberry Human Research Ethics Committee E
Ethics committee address [1] 319515 0
Ethics committee country [1] 319515 0
Australia
Date submitted for ethics approval [1] 319515 0
17/12/2025
Approval date [1] 319515 0
20/01/2026
Ethics approval number [1] 319515 0

Summary
Brief summary
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 147574 0
Dr Thomas Polasek
Address 147574 0
CMAX, Ground Floor, 21-24 North Terrace, Adelaide, South Australia 5000
Country 147574 0
Australia
Phone 147574 0
+61 8 7088 7900
Fax 147574 0
Email 147574 0
[email protected]
Contact person for public queries
Name 147575 0
Kerry Rowe
Address 147575 0
Alterity Therapeutics, Level 15, 500 Collins Street, Melbourne, 3000
Country 147575 0
Australia
Phone 147575 0
+61 3 9349 4906
Fax 147575 0
Email 147575 0
[email protected]
Contact person for scientific queries
Name 147576 0
Dr David Stamler
Address 147576 0
Alterity Therapeutics, Level 15, 500 Collins Street, Melbourne, 3000
Country 147576 0
Australia
Phone 147576 0
+61 3 9349 4906
Fax 147576 0
Email 147576 0
[email protected]

Data sharing statement
Will the study consider sharing individual participant data?
No


What supporting documents are/will be available?

No Supporting Document Provided


Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.