TRIALS
There are currently a number of trials that may be relevant to patients with mutations in the USH 1G gene:
- Stem cell therapy jCyte
- Stem cell therapy Cedars-Sinai
- Medicines ‘translational read-through’ therapie
- Medicine SLO-RP and NAC-ATTACK
- Study vestibulo-cochlear implant (VCI)
MEDICINES SLO-RP
In Australia, a clinical trial phase 1/2 was started with financial support from the Foundation Fighting Blindness
Nacuity Pharmaceuticals launched this trial under the name SLO-RP. The safety and effectiveness of the medicine NPI-001, an experimental antioxidant, will be tested in the coming two years. The medicine appears to be really promising for slowing down the deterioration of eyesight with people suffering from RP and Usher Syndrome, irrespective of which gene is defective or which mutations have taken place.
ROD-CONE THERAPY
Rod-cone therapy is independent of the gene and focused on treating the rods in the eye while keeping the cones intact. The rods of the retina die first (see light and dark).
GENE THERAPY
Saaïd Safieddine and Christine Petit of the Institut Pasteur in France are busy developing gene therapy for the USH1G gene. The USH1C gene does the coding for the SANS protein. Patients with mutations in the USH1G gene do not correctly produce the SANS protein. Safieddine and Petit applied the USH1G gene with the help of an AAV vector to the cochlea and the organ of balance of newborn mice models for USH1G. Twelve weeks after the treatment, the hearing of these mice had slightly improved and the functioning of the organ of balance had almost fully recovered. Using a mouse model, scientists have succeeded in recovering the hearing and the balance with one single local injection.
STEM CELL THERAPY
jCyte, is a company that has developed retinal progenitor cells (RPCs), a type of stem cell that only retinal cells can become. Clinical studies have shown that these cells can reach and even replace diseased retinal cells. The results of a phase 1 / 2a trial have shown that the treatment is safe and does not cause an immune response.
The Los Angeles-based Cedars-Sinai company has also received approval from the FDA to initiate a phase 1 / 2a clinical trial for patients with RP.
MEDICINES TO REDUCE ER-STRESS
Westerfield and colleagues are busy testing various medicines against Parkinson’s disease and Alzheimer’s disease in their zebrafish models for Usher Syndrome. Expectations are that this will slow down the deterioration of the hearing and eyesight of the zebrafish.
INNOVATION AND (MEDICAL) AIDS
Also investigations and studies are conducted in the world that do not specifically offer a solution for people suffering from Usher Syndrome, but that may be of significance for them in the future. Solutions, therapies and medical aids for other disorders can in a later stage be applied to people suffering from Usher Syndrome as well.
IT’S IN THE PROTEINS
The proteins control all processes in our bodies. These proteins are built using codes that have been captured in the DNA. Due to a writing error in the DNA a protein can be produced incorrectly or not at all. Fixing this DNA error changes the production of the protein and so makes the disorder disappear or reduces the symptoms. This is the idea behind the genetic therapies that are now under development throughout the world.
THE CHALLENGES
There are many challenges in research into Usher syndrome. Researchers specifically focus on a methodology, a strategy and / or a specific Usher protein.