MPS IIIBPhase 3TrAnsformNCT07579910
Intracerebroventricular Tralesinidase Alfa in Participants With MPS IIIB (Sanfilippo Syndrome Type B)
A Phase 3 study testing Tralesinidase alfa (TA) in people with MPS IIIB, run by Spruce Biosciences.
Trial summary
The primary objectives of this study are to evaluate the effects of Tralesinidase Alfa (TA) on cognition Read more about this study
- Who is it for?
- Ages 1 year to 5 years
- Conditions the study is for
- MPS IIIB
- What is being tested?
- Tralesinidase alfa (TA)
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 14 participants
- Where
- No sites listed yet
- Study dates
- Dec 2026to Aug 2033
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 1 year to 5 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- Has a diagnosis of MPS IIIB confirmed by deficient NAGLU enzyme activity during screening.
- Has nonattenuated severe MPS IIIB by the Genotype and Clinical Assessment Committee.
- Is ≥1 and ≤5 years of age with BSID-III-C raw score of <70. Is male or female as identified at birth.
Who cannot join
- Genotyped for a known MPS IIIB variant associated with an attenuated phenotype or has a sibling with a known attenuated phenotype.
- Has another neurological illness that may have caused cognitive decline (e.g., trauma, meningitis, or hemorrhage) before study entry.
- Has received stem cell, gene therapy, or enzyme replacement therapy for MPS IIIB.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: A Phase 3, Randomized, Single-blind, Parallel Group, Controlled, Multicenter Study to Evaluate the Safety, Tolerability, and Efficacy of Intracerebroventricular Tralesinidase Alfa Treatment Compared to Standard of Care in Mucopolysaccharidosis Type IIIB (MPS IIIB, Sanfilippo Syndrome Type B)
The primary objectives of this study are to evaluate the effects of Tralesinidase Alfa (TA) on cognition
- Conditions
- MPS IIIB
- Being tested
- Tralesinidase alfa (TA)
- Medical subject headings
- Mucopolysaccharidosis III
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Tralesinidase alfa (TA)Drug
TA study drug is a sterile solution for ICV infusion.
| Study group | Role | What they receive |
|---|---|---|
| Tralesinidase alfa (TA) | Experimental | Not described Receives: Drug: Tralesinidase alfa (TA) |
| Control | No intervention | Not described |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change from Baseline in Bayley Scales of Infant and Toddler Development, Third Edition, Cognition Domain (BSID-III-C) Raw Score
The BSID-III-C is a standardized tool that evaluates cognitive development in young children, capturing skills such as processing speed, problem solving, and play. Raw scores are used to sensitively measure individual change over time, independent of age. Assessments are administered by a trained, blinded rater and reviewed by a central blinded rater. The endpoint is the difference in mean change from baseline in BSID-III-C raw score between the tralesinidase alfa and control arms at Week 260
Measured: Baseline to Week 260 (approximately 5 years)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 May 2026
- Study startDec 2026 (estimated)
- Primary completionAug 2033 (estimated)
- Study completionAug 2033 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for MPS IIIBStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Outcomes assessor
- Enrolment
- 14 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Spruce Biosciences
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07579910
- Sponsor's protocol ID
- 250-301
- Acronym
- TrAnsform
- Status last verified
- Sep 2026
- First submitted
- 28 Apr 2026
- Last updated
- 21 Sep 2026
- Results posted
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 21 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 3, Randomized, Single-blind, Parallel Group, Controlled, Multicenter Study to Evaluate the Safety, Tolerability, and Efficacy of Intracerebroventricular Tralesinidase Alfa Treatment Compared to Standard of Care in Mucopolysaccharidosis Type IIIB (MPS IIIB, Sanfilippo Syndrome Type B)
- ClinicalTrials.gov ID
- NCT07579910
- Acronym / sponsor ID
- TrAnsform / 250-301
- Conditions
- MPS IIIB
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 14 participants (estimated)
- Lead sponsor
- Spruce BiosciencesIndustry (pharma, biotech, devices)
- Study start
- Dec 2026 (estimated)
- Primary completion
- Aug 2033 (estimated)
- Study completion
- Aug 2033 (estimated)
- First posted
- 12 May 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The primary objectives of this study are to evaluate the effects of Tralesinidase Alfa (TA) on cognition
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Tralesinidase alfa (TA) | Experimental | Drug: Tralesinidase alfa (TA) |
| Control | No intervention | – |
Who may qualify
- Ages
- 1 year to 5 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Child
Key inclusion criteria (3 listed)
- Has a diagnosis of MPS IIIB confirmed by deficient NAGLU enzyme activity during screening.
- Has nonattenuated severe MPS IIIB by the Genotype and Clinical Assessment Committee.
- Is ≥1 and ≤5 years of age with BSID-III-C raw score of <70. Is male or female as identified at birth.
Key exclusion criteria (3 listed)
- Genotyped for a known MPS IIIB variant associated with an attenuated phenotype or has a sibling with a known attenuated phenotype.
- Has another neurological illness that may have caused cognitive decline (e.g., trauma, meningitis, or hemorrhage) before study entry.
- Has received stem cell, gene therapy, or enzyme replacement therapy for MPS IIIB.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Tralesinidase alfa (TA)TA study drug is a sterile solution for ICV infusion. | Drug | Tralesinidase alfa (TA) |
Primary outcome
Change from Baseline in Bayley Scales of Infant and Toddler Development, Third Edition, Cognition Domain (BSID-III-C) Raw Score
Time frame: Baseline to Week 260 (approximately 5 years)
The BSID-III-C is a standardized tool that evaluates cognitive development in young children, capturing skills such as processing speed, problem solving, and play. Raw scores are used to sensitively measure individual change over time, independent of age. Assessments are administered by a trained, blinded rater and reviewed by a central blinded rater. The endpoint is the difference in mean change from baseline in BSID-III-C raw score between the tralesinidase alfa and control arms at Week 260
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 21 Sep 2026.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Tralesinidase alfa (TA) in people with MPS IIIB, run by Spruce Biosciences.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 21 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact April Freeman (415-343-5986, info@sprucebio.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change from Baseline in Bayley Scales of Infant and Toddler Development, Third Edition, Cognition Domain (BSID-III-C) Raw Score (time frame: Baseline to Week 260 (approximately 5 years)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Sep 2026.