Safety, Tolerability and Efficacy of ICV AX 250 Treatment in MPS IIIB -OLE

• ClinicalTrials.gov Identifier: NCT05492799
• Recruitment Status: Enrolling by invitation
• First Posted: August 9, 2022
• Last Update Posted: January 18, 2023
• Sponsor: Allievex Corporation
• Information provided by (Responsible Party): Allievex Corporation

Study Description

Brief Summary:

This is a Phase 3B/4, multicenter, multinational, open label study to further evaluate intracerebroventricular (ICV) delivered AX 250 treatment in MPS IIIB subjects that complete Study 250-202 for up to an additional 3 years (144 weeks) of treatment with AX 250 administered by ICV infusion every other week. Subjects will be evaluated for neurocognitive function, communication, adaptive behavior, quality of life, imaging characteristics and biochemical markers of disease burden. Safety will be assessed by adverse events, clinical labs, and physical exams.

Condition or disease	Intervention/treatment	Phase
MPS III B	Drug: AX 250	Phase 4

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 15 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Open-Label Multicenter Extension Study to Further Evaluate Safety, Tolerability and Efficacy of Intracerebroventricular AX 250 Treatment in Mucopolysaccharidosis Type IIIB (MPS IIIB, Sanfilippo Syndrome Type B) Patients
• Actual Study Start Date: December 2, 2022
• Estimated Primary Completion Date: October 2027
• Estimated Study Completion Date: December 2027

Arms and Interventions

Arm	Intervention/treatment
Experimental: single arm; AX 250 300 mg - open label	Drug: AX 250; biweekly infusion by intracerebroventricular (ICV) infusion

Outcome Measures

Primary Outcome Measures :

1. Primary - neurocognition [ Time Frame: baseline to 144 weeks of treatment ]
   the rate of change in score from neurocognitive assessment using validated scale

Eligibility Criteria

• Ages Eligible for Study: Child, Adult, Older Adult
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

1. Must have completed 240 weeks of Study 250-202 and enter 250-401 within 8 weeks of dosing completion.
2. Provides written informed consent from parent or legal guardian and assent from subject, if required
3. Has the ability to comply with protocol requirements in the opinion of the investigator
4. If female with childbearing potential, must have a negative pregnancy test at the Screening visit and be willing to have additional pregnancy tests during the study

Exclusion Criteria:

1. Has (1) a cognitive age equivalent (AEq ) score ≤ 18 months, (2) a development quotient (DQ) score ≤ 20, and (3) no evidence of improvement during the 250-202 study in secondary or exploratory efficacy endpoints
2. Would not benefit from enrolling in the study in the opinion of the investigator
3. Has received stem cell, gene therapy or enzyme replacement therapy (other than AX 250) for MPS IIIB
4. Has a history of poorly controlled seizure disorder
5. Is prone to complications from ICV drug administration including patients with hydrocephalus or ventricular shunts
6. Has received any investigational medication within 30 days prior to the Baseline visit or is scheduled to receive any investigational drug during the course of the study
7. Has a medical condition or extenuating circumstance that, in the opinion of the investigator, might compromise the subject's ability to comply with protocol requirements, the subject's well-being or safety, or the interpretability of the subject's clinical data

Contacts and Locations

Locations

United States, California

UCSF Benioff Children's Hospital Oakland

Oakland, California, United States, 94609

United States, Pennsylvania

UPMC Children's Hospital Pittburgh

Pittsburgh, Pennsylvania, United States, 15224

Colombia

Fundación Cardio Infantil - Instituto de Cardiología

Bogotá,, Colombia

Germany

University Medical Center Hamburg-Eppendorf

Hamburg, Germany

Turkey

Gazi University Faculty of Medicine

Ankara, Turkey

United Kingdom

Great Ormond Street Hospital For Children, NHS Foundation Trust

London, United Kingdom, WC1N 3JH

Sponsors and Collaborators

Allievex Corporation

Investigators

• Study Director: Medical Director; Allievex Corporation

More Information

• Responsible Party: Allievex Corporation
• ClinicalTrials.gov Identifier: NCT05492799
• Other Study ID Numbers: 250-401
• First Posted: August 9, 2022
• Last Update Posted: January 18, 2023
• Last Verified: January 2023

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No

Additional relevant MeSH terms:

Mucopolysaccharidosis III; Mucopolysaccharidoses; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Lysosomal Storage Diseases; Mucinoses; Connective Tissue Diseases; Metabolic Diseases