Intra-cerebral gene therapy for Sanfilippo type B syndrome

ISRCTN ISRCTN19853672
DOI https://doi.org/10.1186/ISRCTN19853672
Secondary identifying numbers MPS3-IP-01
Submission date
30/09/2010
Registration date
03/08/2011
Last edited
30/09/2021
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English Summary

Background and study aims
Sanfilippo syndrome, also known as mucopolysaccharidosis type III (MPS III), is a rare genetic disorder. There are four types (A to D). Sanfilippo syndrome subtype B, or mucopolysaccharidosis type IIIB (MPSIIIB), is caused by a genetic defect of the enzyme α-N-acetylglucosaminidase (NAGLU). This enzyme is involved in breaking down long chains of sugar molecules. In its absence, these molecules build up. This causes brain damage starting most often during the first 5 years of life. Affected children require specific care and death occurs at the average age of 15, although some patients are still alive after the age of 20. MPSIIIB could be treated by delivering the correct gene for the missing enzyme using a virus (gene therapy). The aim of this study is to test this gene therapy approach in patients with MPSIIIB.

Who can participate?
Patients age 18 months to 5 years with MPSIIIB

What does the study involve?
Participants receive gene therapy combined with immunosuppressant drugs (to suppress the strength of the body's immune system). The virus is injected into the brain at 6 injection sites in a single session. Clinical and x-ray examinations are carried out and blood and cerebrospinal fluid samples are taken before and after treatment, with daily follow-up during 1 week after the injections, then 14 and 21 days, 1, 3, 6 and 12 months after treatment.

What are the possible benefits and risks of participating?
Not provided at time of registration

Where is the study run from?
Hôpital Bicêtre (France)

When is the study starting and how long is it expected to run for?
September 2013 to November 2015

Who is funding the study?
1. French Patient Association (France)
2. Private donations (France)

Who is the main contact?
Prof. Marc Tardieu

Contact information

Prof Marc Tardieu
Scientific

Service de Neurologie Pédiatrique
Hôpital Bicêtre
Assistance Publique - Hôpitaux de Paris
78, rue du Général Leclerc
Le Bicêtre-Bicêtre
94275
France

Study information

Study designPhase I/II single-arm open-label study
Primary study designInterventional
Secondary study designNon randomised study
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titleA phase I/II, open-label, study of intracerebral administration of adeno-associated viral vectors carrying human NaGlu cDNA for the treatment of Sanfilippo type B syndrome
Study acronymMPS3B
Study hypothesisThere is currently no available treatment for Sanfilippo syndrome. The rationale for therapeutic approaches in mucopolysaccharidoses (MPS) is based on the observation that delivery of the missing enzyme reverses phenotypic abnormalities in genetically deficient cells. Although enzyme replacement therapy (ERT) is being explored, there is still not currently available for MPSIIIB.

On the other hand, MPS have long been recognized as prime candidate diseases for gene therapy as it was shown that the missing enzyme may be produced and distributed to the organism by a group of genetically modified cells.

Indeed, numerous studies in animal models of MPS have described the effects of genetic modification of tissues including bone marrow, skin, muscle, liver and brain, resulting in the production of a therapeutically active enzyme.

However, when vectors are administered in the periphery, the produced enzymes do not cross the blood-brain barrier. Only very high doses of enzyme in the circulation may result in detectable transport into the brain.

In MPSIII, a direct administration into the brain would be required, since most lesions take place in this organ.
Ethics approval(s)CCP Il-de-France II, 17/04/2013, ref: 2013-03-17
ConditionMucopolysaccharidose - neurodegenerative disease
InterventionPatients will receive gene therapy combined with immunosuppressant regimen. The vector is a serotype 2 AAV genome encoding the human α-N-acetylglucosaminidase cDNA packaged in a serotype 5 capsid called AAV-NAGLU. Vector suspensions will be simultaneously injected into the brain parenchyma at 6 injections sites in a single neurosurgical session. Combined immunosuppression (Tacrolimus, Cell-Cept) is justified by previous studies in children receiving recombinant enzyme infusions and investigations of AAV-mediated gene therapy in Sanfilippo and Hurler dogs.

Clinical and radiological examination, collection of biological products including blood, peripheral blood mononucleated cells and cerebrospinal fluid (CSF) > 6 weeks prior to treatment, at inclusion, baseline, 14 days prior to treatment, observation and -2 and -1 days, daily follow-up during 1 week post-injection, then 14 and 21 days, 1, 3, 6 and 12 months post-treatment.

The total duration of follow up is 1 year.

Added 02/08/2013:
Vectors will be delivered through 8 small burr holes. Two in the posterior fossa to target the white matter of the cerebellar hemisphers and six supratentorially, to target the white matter adjacent to the putamen. Two deposits will be done on each track, one deep and one superficial, in a single neurosurgical session.
Intervention typeDrug
Pharmaceutical study type(s)
PhasePhase I/II
Drug / device / biological / vaccine name(s)Intra-cerebral gene therapy
Primary outcome measureClinical, radiological, biological tolerance associated to the proposed treatment
Secondary outcome measuresCollection of data to define exploratory tests that will become evaluation criteria for further clinical phase III efficacy studies (brain MRI; neurological and biological markers)
Overall study start date01/09/2013
Overall study end date01/11/2015

Eligibility

Participant type(s)Patient
Age groupChild
Lower age limit18 Months
Upper age limit5 Years
SexBoth
Target number of participants4 children from Europe
Total final enrolment4
Participant inclusion criteria1. Age: 18 months to the end of the 5th year
2. Onset of clinical manifestations related to MPSIIIB during the first 5 years of life
3. NaGlu activity in peripheral blood cell and/or cultured fibroblast extracts of less than 10% of controls
4. Patient affiliated to a social security regimen
5. Family understanding the procedure and the informed consent
6. Vital laboratory parameters within normal range

Sanfilippo disease is a rare disease and so the countries of recruitment will depend on the availabilities of the patient at the time of recruitment. There will be one study centre in France.
Participant exclusion criteria1. Presence of brain atrophy on pre-inclusion MRI judged on a cortico-dural distance of more than 1 cm
2. Any condition that would contraindicate permanently anaesthesia
3. Any other permanent medical condition not related to MPSIIIB
4. No independent walking (Ability to walk without help)
5. Any vaccination 1 month before vector injection
6. Receipt of aspirin within one month
7. Any medication aiming at modifying the natural course of MPSIIIB given during the 6 months before vector injection
Recruitment start date01/09/2013
Recruitment end date01/11/2015

Locations

Countries of recruitment

  • France

Study participating centre

Hôpital Bicêtre
Le Bicêtre-Bicêtre
94275
France

Sponsor information

Institut Pasteur (France)
Industry

25-28 Rue du Dr Roux
Paris
75015
France

Website http://www.pasteur.fr/ip/index.jsp
ROR logo "ROR" https://ror.org/0495fxg12

Funders

Funder type

Charity

French Patient Association (France)

No information available

Private donations (France)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 01/09/2017 18/12/2020 Yes No
Results article results 10/05/2021 30/09/2021 Yes No

Editorial Notes

30/09/2021: Publication reference added.
18/12/2020: The following changes were made to the trial record:
1. Publication reference added.
2. The total final enrolment was added.
11/05/2017: Plain English summary added.
06/08/2013: The overall trial start date was changed from 01/06/2012 to 01/09/2013 and the overall trial end date was changed from 01/12/2015 to 01/11/2015.
02/08/2013: The target number of participants was changed from 8 to 4.