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

Phase 4

• Conditions: MPS III B
• Interventions: Drug: AX 250

• Registration Number: NCT05492799
• Lead Sponsor: Allievex Corporation

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.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2022-08-05
• Study First Submitted QC: 2022-08-08
• Study First Posted: 2022-08-09
• Study Start: 2022-12-02
• Status Verified: 2023-08
• Last Update Submitted: 2023-08-07
• Last Update Posted: 2023-08-09
• Primary Completion: 2027-10
• Study Completion: 2027-12

Recruitment & Eligibility

• Status: ENROLLING_BY_INVITATION
• Sex: All
• Target Recruitment: 15

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

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
single arm	AX 250	AX 250 300 mg - open label

Primary Outcome Measures

Name	Time	Method
Primary - neurocognition	baseline to 144 weeks of treatment	the rate of change in score from neurocognitive assessment using validated scale

Trial Locations

Locations (6)

University Medical Center Hamburg-Eppendorf; 🇩🇪 Hamburg, Germany

Great Ormond Street Hospital For Children, NHS Foundation Trust; 🇬🇧 London, United Kingdom

UPMC Children's Hospital Pittburgh; 🇺🇸 Pittsburgh, Pennsylvania, United States

UCSF Benioff Children's Hospital Oakland; 🇺🇸 Oakland, California, United States

Fundación Cardio Infantil - Instituto de Cardiología; 🇨🇴 Bogotá,, Colombia

Gazi University Faculty of Medicine; 🇹🇷 Ankara, Turkey