Dialog Box


Therapeutic Avenues

There are several approaches being investigated for the treatment of Sanfilippo. Whilst the cause of the disease is fairly well understood, treating the disease presents researchers and clinicians with a number of challenges.

Introduction   |    Gene Therapy  |   Stem Cell Therapy   |   ERT   |   SRT   |   Palliative Treatments



Sanfilippo is caused by changes to genes that prevents the body from producing enzymes that are needed to recycle waste within the cells of the body.  Sanfilippo mostly affects the Central Nervous System (CNS), especially the brain so for a treatment to be effective it needs to be able to reach the brain. This means crossing the Blood-Brain-Barrier (BBB)  a natural filter that protects the brain by stopping toxins and infections present in the blood from entering. Most traditional drugs can travel through the bloodstream but not cross the BBB.


The different approaches researched all try to address the recycling problem and disease symptoms in a different way. To date, Gene Therapy (GT) and Enzyme Replacement Therapy (ERT) represent the most advanced and promising avenues for finding a treatment for Sanfilippo patients.

For details on current research programs, please see our Current Research Programs section.


Gene Therapy (GT)


What is it?


Gene Therapy is a treatment approach that involves introducing genetic material into a person’s cells to fight or prevent the disease. Gene Therapy has been researched for more than 20 years with over 1,000 human clinical trials conducted for many genetic conditions such as severe combined immuno-deficiencies, haemophilia, Parkinson's disease, cancer and even HIV.


A gene can be delivered to a cell using a "vehicle" or agent known as a vector. The most common types of vectors used in gene therapy are viruses, which are altered to make them safe. Whilst the technology is still fairly new and some risks exist, it has been used with some success and the first gene therapy product was given regulatory approval in 2013 (for lipoprotein lipase deficiency) and others have followed for a type of immune deficiency, a form of inherited blindness and certain cancers.


To find out more about Gene Therapy:


How does it work for Sanfilippo?


For Sanfilippo, gene therapy aims to introduce a healthy copy of the faulty gene into a patient to enable the missing enzyme to be produced in the patient's own cells. A virus carrying the gene is injected via a single procedure and is spread to the patient's cell which can then start producing the enzyme that is missing (or produced in insufficient quantities). To address the challenge of crossing the BBB, the product is either administered directly into the brain or the cerebrospinal fluid (CSF), or a type of virus that is able to cross the blood brain barrier is used.


Gene therapy for Sanfilippo is currently at clinical trial stage.


Stem Cell Therapy


What is it?


Stem cells are unspecialised cells that can develop into the many specialised cell types of the body, such as muscle cells, red blood cells or brain cells. They can also multiply so that their supply doesn't run out. They are essential for growth and repair of the body.


The most well-known type of stem cell therapy is bone marrow transplant for blood diseases such as leukaemia. In this case, the stem cells are taken from another person who does not have the disease and transplanted into the patient, but there are often problems with the patient rejecting the transplanted cells.  


Alternatively, cells from the patient are extracted and corrected using gene therapy before being re-implanted. 

To find out more about stem cell therapy:



How does it work for Sanfilippo?


Stem cells are taken from the bone marrow or blood and the genetic fault corrected using gene therapy so that they overproduce the missing enzyme. These genetically engineered cells are then transplanted back into the patient.

Stem cell therapy for Sanfilippo is currently at pre-clinical trial stage.


Enzyme Replacement Therapy (ERT)


What is it?


ERT aims to replace an enzyme that is deficient or absent. The replacement enzyme is referred to as a “recombinant” enzyme, produced in a laboratory. Usually this is done by giving the patient an intravenous (IV) infusion containing the enzyme.

Enzyme replacement therapy does not correct the underlying genetic defect so life-long treatments with regular infusions is needed (for example weekly or monthly).


ERT has been proven to be highly effective for other lysosomal storage conditions, for example such as Gaucher disease, Fabry disease, MPS I (Hurler syndrome), MPS II, MPS VI and Pompe disease.

How does it work for Sanfilippo?


For Sanfilippo, as the enzyme is not usually able to cross the Blood-Brain-Barrier, which creates additional challenges and several trials have failed to show that it is effective. However, trials have now started where the enzyme has been modified to improve its ability to reach the cells of the brain and utilising different administration methods. 


Enzyme Replacement Therapy for Sanfilippo is currently at clinical trial stage.


Substrate Reduction Therapy (SRT)


What is it?


The objective of SRT is to decrease the production of substrate which accumulates because it is not degraded. To put it simply, produce less to store less.


How does it work for Sanfilippo?


The objective of SRT for Sanfilippo is to use a drug that helps the body produce less complex sugars or GAGs (which is the substrate) so there is less that accumulates in the cells. Several drugs have been formally trialled:

  • the trial of Miglustat concluded that it did not have a positive effect on the disease
  • the trial of Genistein concluded that it did not give any clinically meaningful benefit

Further research is ongoing in the laboratory to search for other drugs that may be able to be used as Substrate Reduction Therapy for Sanfilippo.


Palliative Treatments


Palliative care is any form of medical care or treatment that concentrates on reducing the severity of disease symptoms. The goal is to prevent and relieve suffering and to improve quality of life for people facing serious, complex illness. This support encompasses aspects such as respite care, symptom management and bereavement support and may extend over a period of time. An assessment of medical need and a care plan can lead to support provided to the child and family so both can experience a better quality of life.


A number of therapies and approaches are used to manage the symptoms of Sanfilippo and include:


  • Speech therapy
  • Occupational Therapy
  • Physical therapy
  • Behavioural therapy
  • Diet
  • Anti-seizure medications
  • Ear, nose and throat therapies
  • Medications for heart problems
  • Educational interventions