Study of ASN51 in Adults With Early Alzheimer's Disease

A Phase 2, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study of ASN51 in Adults With Early Alzheimer's Disease

The main purpose of this study is to evaluate the safety, tolerability, and effect on biomarkers of disease pathophysiology and pathology, pharmacokinetics (PK), and preliminary effects on measures of clinical efficacy of multiple doses of ASN51 in adult participants with early Alzheimer's disease (AD).

Study Overview

• Status: Terminated
• Conditions: Alzheimer Disease
• Intervention / Treatment: Drug: Placebo; Drug: ASN51

• Study Type: Interventional
• Enrollment (Actual): 123
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Florida
    • Clermont, Florida, United States, 34711
      • K2 Medical Research
    • Lady Lake, Florida, United States, 32159
      • K2 Medical Research - The Villages
    • Maitland, Florida, United States, 32751
      • K2 Medical Research
    • Stuart, Florida, United States, 34997
      • Alzheimer's Treatment and Research Center
    • Wellington, Florida, United States, 33414
      • Alzheimer's Treatment and Research Center
  • Georgia
    • Columbus, Georgia, United States, 31909
      • Columbus Memory Center, LLC
  • Virginia
    • Fairfax, Virginia, United States, 22031
      • Re:Cognition Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

1. Male or female age 50 to 80 years.
2. A clinical diagnosis of Alzheimer's disease (AD) at either the mild cognitive impairment or mild AD dementia stage per National Institute on Aging and the Alzheimer's Association, consistent with Stage 3 and Stage 4 in the Food and Drug Administration (FDA) draft guidance for early AD.
3. Mini-Mental State Examination score of 20 to 28 (inclusive).
4. A plasma pTau217 result consistent with the presence of amyloid pathology.
5. Must have a care partner who, in the investigator's judgment, has frequent and sufficient contact with the participant as to be able to provide accurate information about the participant's cognitive and functional abilities. The care partner must be literate and provide informed consent.

Key Exclusion Criteria:

1. Any medical or neurological/neurodegenerative condition (other than AD) that, in the opinion of the Investigator, might be a contributing cause to the participant's cognitive impairment (e.g., current history of substance abuse, uncontrolled vitamin B12 deficiency or abnormal thyroid function, stroke or other cerebrovascular condition, normal pressure hydrocephalus, Parkinson's Disease, Lewy body dementia, cerebral amyloid angiopathy, frontotemporal dementia) or could lead to discontinuation, lack of compliance, interference with study assessments, or safety concerns.
2. Non-amnestic presentation of AD as judged by the investigator.
3. Woman of childbearing potential.
4. Any prior or ongoing exposure to active or passive anti-amyloid immunotherapy, anti-tau immunotherapy, an anti-tau antisense oligonucleotide or gene therapy, or O-linked-β-N-acetylglucosaminidase (O-GlcNAcase) inhibitor.

Other protocol defined inclusion and exclusion criteria could apply.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ASN51: Low Dose; Participants were to receive low dose of ASN51 orally, once daily (QD) for up to 24 weeks in the double-blind placebo-controlled intervention period or up to 36 weeks long-term extension period.	Drug: ASN51; Oral capsules
Experimental: ASN51: High Dose; Participants were to receive high dose of ASN51 orally, QD for up to 24 weeks in the double-blind placebo-controlled intervention period or up to 36 weeks long-term extension period.	Drug: ASN51; Oral capsules
Placebo Comparator: Placebo; Participants were to receive ASN51 matching placebo orally, QD for up to 24 weeks in the double-blind placebo-controlled intervention period.	Drug: Placebo; Oral capsules

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of Participants With Adverse Events (AEs)	An adverse event (AE) is any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug related.	From first dose up to end of the study up to Week 28
Change From Baseline in Columbia-Suicide Severity Rating Scale (C-SSRS)	C-SSRS is used to assess the suicidality of participants and assessment includes "yes" or "no" responses for 5 questions, each related to suicidal ideation and suicidal behavior. Numeric ratings are provided for suicidal ideation (score ranges from 1 to 5, where higher scores indicate more suicidal ideation) and suicidal behavior (score ranges from 0 to 4 where higher total scores indicate more suicidal behavior).	Baseline up to Week 28

Secondary Outcome Measures

Outcome Measure	Time Frame
Change From Baseline in Plasma pTau217 Through Week 24	Baseline through Week 24
Maximum Plasma Concentration (Cmax) of ASN51 at Steady State	Pre-dose on Day 1 and at multiple time points post-dose up to Week 24
Change From Baseline in Cerebrospinal Fluid (CSF) Plasma Tau Phosphorylated at Threonine-217 (pTau217) Through Week 24	Baseline through Week 24
Change From Baseline in CSF Total Tau Protein Through Week 24	Baseline through Week 24
Change From Baseline in MK-6240 Tau Positron Emission Tomography (PET) Signal Through Week 24	Baseline through Week 24
Trough Plasma Concentration (Cmin) of ASN51 in Plasma at Steady State	Pre-dose on Day 1 and at multiple time points post-dose up to Week 24

Collaborators and Investigators

• Sponsor: Asceneuron S.A.

Study record dates

Study Major Dates

• Study Start (Actual): October 16, 2024
• Primary Completion (Actual): November 8, 2024
• Study Completion (Actual): November 8, 2024

Study Registration Dates

• First Submitted: November 5, 2024
• First Submitted That Met QC Criteria: November 5, 2024
• First Posted (Actual): November 6, 2024

Study Record Updates

• Last Update Posted (Actual): June 29, 2025
• Last Update Submitted That Met QC Criteria: June 13, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Alzheimer's Disease; ASN51
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Mental Disorders; Neurocognitive Disorders; Dementia; Tauopathies; Neurodegenerative Diseases; Alzheimer Disease
• Other Study ID Numbers: ASN51-201

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No