What side effects are associated with this type of intervention?

In the study of intrathecal heparan-N-sulfatase (rhHNS) for Sanfilippo Syndrome type A, the treatment was generally well tolerated, but it did not slow neurocognitive decline. The study did not report severe adverse events directly related to the drug, but it was terminated early due to not meeting pre-specified efficacy criteria. This suggests that while the treatment was safe, it was not effective in improving cognitive function.

What prior FDA approvals exist?

There are currently no FDA-approved treatments specifically for Sanfilippo Syndrome (MPS III) that involve direct delivery to the brain via an ICV reservoir and catheter. AX 250 is being studied for its potential to improve cognitive function in MPS IIIB patients through this method. Most treatments for Sanfilippo Syndrome are supportive and symptomatic, focusing on managing complications rather than addressing the underlying cause.

What other types of research exist?

Promising novel alternatives to AX 250 for Sanfilippo Syndrome (MPS IIIB) patients may include gene therapy approaches, which aim to correct the underlying genetic defect, and enzyme replacement therapies that deliver the missing enzyme directly to the brain. Additionally, advanced drug delivery systems, such as intrathecal or intracerebroventricular administration of therapeutic agents, are being explored to improve cognitive function and safety in neurodegenerative diseases.

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Enzyme Replacement Therapy

AX 250 for Sanfilippo Syndrome

Phase 2

Waitlist Available

Research Sponsored by Allievex Corporation

Eligibility Criteria Checklist

Specific guidelines that determine who can or cannot participate in a clinical trial

Must have

Males and females who are of reproductive age should practice true abstinence, defined as no sexual activity, during the study and for 6 months after the study has been completed (or withdrawal from the study). If sexually active and not practicing true abstinence, males and females of reproductive age must use a highly effective method of contraception while participating in the study.

Be younger than 65 years old

Must not have

Has contraindications for neurosurgery (eg, congenital heart disease, severe respiratory impairment, or clotting abnormalities)

Has a history of poorly controlled seizure disorder

Timeline

Screening 3 weeks

Treatment Varies

Follow Up entire study period, up to 240 weeks

Awards & highlights

Summary

This trial tests the safety and effectiveness of AX 250, a drug delivered directly to the brain through an implanted device, in improving cognitive function in patients with MPS IIIB.

Who is the study for?

This trial is for patients with Mucopolysaccharidosis Type IIIB who completed a previous study and can follow the new study's rules. They must not be pregnant, agree to use contraception or practice abstinence, and cannot have severe seizures, prior gene therapy/stem cell treatments (other than AX 250), or conditions making intraventricular drug delivery risky.

What is being tested?

The trial tests the long-term safety of AX 250 delivered through an implanted device in the brain and its effects on cognitive function over time in individuals with MPS IIIB. Participants previously treated with AX 250 continue treatment to assess ongoing impacts.

What are the potential side effects?

While specific side effects are not listed here, potential risks may include complications from drug delivery via an implanted brain device, reactions to AX 250 itself, or issues related to long-term treatment affecting cognitive functions.

Eligibility Criteria

Inclusion Criteria

You may be eligible if you check “Yes” for the criteria below

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I will not have sex or will use effective birth control during and for 6 months after the study.

Exclusion Criteria

You may be eligible for the trial if you check “No” for criteria below:

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I cannot have brain surgery due to heart, lung, or clotting issues.

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I have a history of seizures that are hard to control.

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I have received treatments like stem cell, gene therapy, or ERT for MPS IIIB.

Timeline

Screening ~ 3 weeks3 visits

Treatment ~ Varies

Follow Up ~ entire study period, up to 240 weeks

Screening ~ 3 weeks

Treatment ~ Varies

Follow Up ~entire study period, up to 240 weeks

This trial's timeline: 3 weeks for screening, Varies for treatment, and entire study period, up to 240 weeks for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.

Secondary study objectives

Evaluate the impact of long-term AX 250 treatment on adaptive function derived from the Vineland Adaptive Behavior Scales, 2nd edition (VABS-II)

Evaluate the impact of long-term AX 250 treatment on cognitive function in up to 33 patients with MPS IIIB as assessed by age equivalent score (AEq)

Trial Design

1Treatment groups

Experimental Treatment

Group I: AX 250Experimental Treatment1 Intervention

All subjects will receive AX 250 at the MTTD established in 250-201, 300mg administered weekly by ICV infusion that will continue for up to 240 weeks.

Treatment

First Studied

Drug Approval Stage

How many patients have taken this drug

AX 250

2016

Completed Phase 2

~30

0 / 4Eligibility criteria met

Research Highlights

Information in this section is not a recommendation. We encourage patients to speak with their healthcare team when evaluating any treatment decision.

Mechanism Of Action

Side Effect Profile

Prior Approvals

Other Research

Sanfilippo Syndrome treatments focus on addressing enzyme deficiencies that lead to the accumulation of heparan sulfate in the brain. AX 250, delivered directly to the brain via an ICV reservoir and catheter, exemplifies this approach by bypassing the blood-brain barrier to ensure the enzyme reaches the central nervous system. This direct delivery is crucial for improving cognitive function and slowing neurological decline, which are significant concerns for patients with Sanfilippo Syndrome.