Retinitis pigmentosa (RP), a genetic disorder of the eyes, is one of the leading causes of blindness. Thought to affect around one in 4,000 people (or two million worldwide), it typically begins with a loss of night vision and a narrowing of the visual field. Over time, the patient’s vision deteriorates, sometimes reaching the point of total blindness.
At present, there is no cure for the disease. More properly described as a group of diseases rather than a single condition, RP is associated with mutations in over 60 genes. The ideal treatment, then, would be a gene-independent therapy that could treat all forms of RP.
For French biotech company SparingVision, this goal could be in sight. The company, which focuses on innovative therapeutic approaches for inherited retinal diseases, is developing a drug candidate (SPVN06) that could treat RP irrespective of genetic pathology.
Following its latest funding award – €2.5m from the EU’s EIC accelerator programme – SparingVision is now working to advance the treatment into clinical trials. Florence Allouche Ghrenassia, president and CEO, tells us more.
Abi Millar: SparingVision is developing a new drug for retinitis pigmentosa. Can you tell me a bit about this condition? How great is the need for new therapies?
Florence Allouche Ghrenassia: Retinitis pigmentosa (RP) is a rare, inherited retinal disorder characterised by diffuse progressive dysfunction of photoreceptors (primarily rod photoreceptors). It subsequently leads to degeneration of cone photoreceptors and the retinal pigment epithelium. This degenerative disease causes blindness in young people and adults.
Many believe that corrective ophthalmology gene therapy is the future for rare genetic disease. But, since the corrective gene therapy only treats one out of 65 mutations in this condition, it means the group of patients that can be targeted is very small.
AM: Your drug, SPVN06, is a gene-independent drug candidate that could treat all forms of the disease, by using a protein that slows down the degeneration of cones. Can you tell me more about how it works?
FAG: We have developed an innovative treatment that can stop the evolution of this blindness, the first vision-saving treatment of its kind.
What makes it different? In 2004, José Sahel and Thierry Léveillard identified that in this disease, the main factor that leads to blindness is a loss of RdCVF (rod-derived cone variability factor). This is a factor secreted by the rods that serves as neuroprotector and anti-oxidative and is necessary to maintain day vision. When there is a mutation in the rods, RdCVF is no longer present. This causes cone function to degenerate, leading to cell death and blindness. In RP, the blindness occurs over a 15-year period and starts between the ages of 20 and 30.
SparingVision’s product, SPVN06, leads to the production of RdCVF. With a single injection under the retina, it can treat all genetic forms of RP, providing patients with long lasting efficacy. It protects the cones by stimulating the glucose metabolism, and repairs the oxidative damage.
In our proof of concept, using SPVN06 in mice models provided almost immediate protection and repair to the cones and the progression of blindness was stopped.
AM: SparingVision was recently awarded €2.5m of non-dilutive funding from the European EIC Accelerator. How did this funding come about and what will it be used for?
FAG: SparingVision met the criteria for this very selective funding call. We are a biotech company and a small enterprise, with high risks and high potential. We are developing and bringing to the market an innovative product that could drive economic growth.
The company strategy was evaluated as excellent, along with the financial planning and projections, the ability of the team to bring the product to market, and, above all, the novelty and disruptiveness of our therapeutic approach. The product was evaluated as having a significant potential impact on the market and on patients’ lives.
This funding will allow SparingVision to accelerate its clinical and regulatory development. Currently, we are producing clinical batches to begin our first clinical trials in Europe and the United States in 2020.
AM: You will soon be initiating the PHENOROD II prospective study. What did the first arm of the study (PHENOROD I) involve and how will PHENOROD II build on this?
FAG: In 2018, SparingVision started the PHENOROD I retrospective study to describe the natural history of RP from clinical records of patients in the ‘Centre Hospitalier National d’Ophtalmologie 15-20’. To deepen our knowledge on the disease and the progression profile of affected patients, SparingVision will conduct a prospective study (PHENOROD II) on 80 patients. This will fill in the information gap on the disease, evaluate new markers of progression, and identify patients with fast-progressing disease who will likely benefit from our therapy.
AM: What are the next steps in the path to clinical approval and what are your goals over the longer term? What could the implications be for people with retinal diseases if your treatment is approved?
FAG: The product development has been secured with strong intellectual property, exclusive licenses and research collaboration agreements. The manufacturing process is ongoing with the production of the first GMP batches. Following the Natural History study and the Prospective Study, the Phase I/II clinical trial is planned for 2020. The company is also seeking to raise €40m in a Series B round that would take us through completion of the Phase III trial.
Behind this product is a very strong team, a world-renowned scientific advisory board, and a strong board of investors. These include Foundation Fighting Blindness, Bpifrance and Fondation Voir et Entendre, who together invested €15.5m in equity. SparingVision also benefits from the support of the Retinal Dystrophies community – physicians, research centres in Europe and the US, and patient advocacy groups.
The challenge for SparingVision – and the opportunity for patients – will be to provide a unique breakthrough product treating all forms of RP and stopping the evolution of the disease.