A Pivotal Study of N-Acetyl-L-Leucine on Ataxia-Telangiectasia (A-T)

NCT06673056 | Active Not Recruiting Phase 3 DMC FDA Drug

• 1 other identifier: IB1001-303
• Study Type: interventional
• Target: 60
• Locations: 6 countries
• Sites: 11

Brief Summary

A pivotal, randomized, double-blind, placebo-controlled, multi-center therapeutic study for patients age 4 and older with a confirmed diagnosis of Ataxia-Telangiectasia (A-T). The objective of this study is to evaluate the safety, tolerability and efficacy of N-acetyl-L-leucine (IB1001) compared to standard of care.

Conditions

Ataxia-Telangiectasia; Ataxia-Telangiectasia (A-T)

Keywords

Ataxia-Telangiectasia; Louis Bar Syndrome

Outcome Measures

Primary Outcomes (1)

• Scale for the Assessment and Rating of Ataxia

  The Scale for Assessment and Rating of Ataxia has 8 items that are related to gait, stance, sitting, speech, finger-chase test, nose-finger test, fast alternating movements, and heel-shin test. The range is 0-40 points, with a lower score representing neurological improvement and a higher score representing neurological worsening.

  End of Period I (week 12) vs. End of Period 2 (week 24)

Secondary Outcomes (5)

• Spinocerebellar Ataxia Functional Index (SCAFI)

  End of Period I (week 12) vs. End of Period 2 (week 24)

• Physician's / Caregiver's / Patient's Clinical Global Impressions (CGI)

  End of Period I (week 12) vs. End of Period 2 (week 24)

• EuroQuol- 5 Dimension (EQ-5D) Quality of Life Scale

  End of Period I (week 12) vs. End of Period 2 (week 24)

• International Cooperate Ataxia Rating Scale (ICARS)

  End of Period I (week 12) vs. End of Period 2 (week 24)

• Neuro Quality of Life - Upper Extremity Function (NeuroQOL-UEF)

  End of Period I (week 12) vs. End of Period 2 (week 24)

Study Arms (2)

N-acetyl-L-leucine (IB1001)

EXPERIMENTAL

Oral administration (granule in a sachet for suspension in water, orange juice, or almond milk). Patients will receive a total daily dose of 2-4 g/day based on weight-tiered doses.

Drug: N-Acetyl-L-Leucine

Placebo comparator

PLACEBO COMPARATOR

Oral administration (granule in a sachet for suspension in water, orange juice, or almond milk). Patients will receive a total daily dose of 2-4 g/day based on weight-tiered doses.

Other: Placebo

Interventions

N-Acetyl-L-Leucine DRUG

N-Acetyl-L-Leucine is a modified amino-acid ester that is orally administered (granules for suspension in a sachet)

Also known as: IB1001, levacetylleucine

N-acetyl-L-leucine (IB1001)

Placebo OTHER

Matching Placebo Sachet

Placebo comparator

Eligibility Criteria

• Age: 4 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• \. Written informed consent signed by the patient and/or their legal representative / parent/ impartial witness 2. Male or female aged ≥4 years with a genetically confirmed diagnosis of A-T at the time of signing informed consent.
• \. Females of childbearing potential, defined as a premenopausal female capable of becoming pregnant, will be included if they are either sexually inactive (sexually abstinent for 14 days prior to the first dose and confirm to continue through 28 days after the last dose) or using one of the following highly effective contraceptives (i.e. results in \<1% failure rate when used consistently and correctly) 14 days prior to the first dose continuing through 28 days after the last dose:
• intrauterine device (IUD);
• surgical sterilization of the partner (vasectomy for 6 months minimum);
• combined (estrogen or progestogen containing) hormonal contraception associated with the inhibition of ovulation (either oral, intravaginal, or transdermal);
• progestogen only hormonal contraception associated with the inhibition of ovulation (either oral, injectable, or implantable);
• intrauterine hormone releasing system (IUS);
• bilateral tubal occlusion. 4. Females of non-childbearing potential who have undergone one of the following sterilization procedures at least 6 months prior to the first dose:
• <!-- -->
• hysteroscopic sterilization;
• bilateral salpingectomy;
• hysterectomy;
• bilateral oophorectomy; OR be postmenopausal with amenorrhea for at least 1 year prior to the first dose and follicle stimulating hormone (FSH) serum levels consistent with postmenopausal status. FSH analysis for postmenopausal women will be done at screening. FSH levels should be in the postmenopausal range as determined by the central laboratory.
• \. If male, patient agrees not to donate sperm from the first dose until 90 days after their last dose.
• \. Patients must fall within:

You may not qualify if:

• \. Patients who have any known hypersensitivity or history of hypersensitivity to:
• Acetyl-Leucine (DL-, L-, D-) or derivatives.
• Excipients the IB1001 sachet (namely isomalt, hypromellose, and strawberry flavor).
• Excipients the placebo sachet (namely isomalt, hypromellose, strawberry flavor, citric acid, microcrystalline cellulose, lactose, denatonium benzoate).
• \. Simultaneous participation in another clinical study or participation in any clinical study involving administration of an investigational medicinal product (IMP; 'study drug') for at least 42 days prior to Visit 1. At the discretion of the investigator, Medical Monitor, and Sponsor, the washout period for specific IMPs may be longer based on the pharmacological activity and pharmacokinetics of the drug.
• \. Patients with a physical or psychiatric condition which, at the investigator's discretion and in consultation with the Medical Monitor and Sponsor (as applicable), may put the patient at risk, may confound the study results, or may interfere with the patient's participation in the clinical study, i.e. reliably perform study assessments.
• \. Known or persistent use, misuse, or dependency of medication, drugs, or alcohol.
• \. Current or planned pregnancy or women who are breastfeeding. 6. Patients with severe vision or hearing impairment (that is not corrected by glasses or hearing aids) that, at the investigator's discretion, interferes with their ability to perform study assessments.
• \. Patients who have been diagnosed with arthritis or other musculoskeletal disorders affecting joints, muscles, ligaments, and/or nerves that by themselves affects patient's mobility and, at the investigator's discretion, interferes with their ability to perform study assessments.
• \. Patients unwilling and/or not able to undergo a 42-day washout period from any of the following prohibited medication prior to Visit 1 (Baseline 1) and remain without prohibited medication through Visit 6.
• <!-- -->
• N-Acetyl-DL-Leucine (e.g. Tanganil®);
• N-Acetyl-L-Leucine (prohibited if not provided as IMP in the IB1001-303 trial);
• Sulfasalazine;
• Rosuvastatin.

Sponsors & Collaborators

• IntraBio Inc: lead

Study Sites (11)

University of California Los Angeles

Los Angeles, California, 90095, United States

Location

Massachusetts General Hospital

Boston, Massachusetts, 02114, United States

Location

The University of Texas Health (UT Health)

Houston, Texas, 77030, United States

Location

University of Cologne

Cologne, 50937, Germany

Location

University of Giessen

Giessen, 35392, Germany

Location

Comenius University Bratislava

Bratislava, 814 99, Slovakia

Location

University Hospital L. Pasteur

Košice, 040 11, Slovakia

Location

Hospital Universitario La Paz

Madrid, 28046, Spain

Location

University of Bern

Bern, 3012, Switzerland

Location

Royal Papworth Hospital

Cambridge, United Kingdom

Location

University of Nottingham

Nottingham, United Kingdom

Location

MeSH Terms

Conditions

Ataxia Telangiectasia

Interventions

acetylleucine; IB1001

Condition Hierarchy (Ancestors)

Spinocerebellar Ataxias; Cerebellar Ataxia; Cerebellar Diseases; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurocutaneous Syndromes; Ataxia; Dyskinesias; Neurologic Manifestations; Telangiectasis; Vascular Diseases; Cardiovascular Diseases; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Primary Immunodeficiency Diseases; DNA Repair-Deficiency Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Immunologic Deficiency Syndromes; Immune System Diseases

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Randomized, placebo-controlled, double-blind, crossover, multi-center, study with 1:1 randomization of IB1001 plus SOC for 12-weeks versus placebo plus SOC for 12-weeks, followed by open-label extension study.

Study Record Dates

• First Submitted: October 31, 2024
• First Posted: November 4, 2024
• Study Start: March 18, 2025
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): June 1, 2028
• Last Updated: July 3, 2025

Record last verified: 2025-06

Data Sharing

• IPD Sharing: Will not share

Locations

GB (2); SL (2); ES (1); CH (1); DE (2); US (3)