SparingVision completes dosing in PRODYGY trial of SPVNO6 for retinitis pigmentosa.
SparingVision have announced this week that they have dosed all participants in their phase 1/2 PRODYGY clinical trial for SPVN06, a gene agnostic therapy aimed at slowing disease progression in Retinitis Pigmentosa (RP).
What is Retinitis Pigmentosa?
RP is one of the most common types of inherited retinal disease (IRD), associated with faults in over 100 genes, affecting around 1 in 4,000 people globally. RP causes progressive vision loss, starting peripherally, due to the loss of light-sensing photoreceptor cells in the retina. To learn more, please watch this short animation video on Inherited Retinal Disease
What is SPVN06?
SPVN06 is an adeno-associated viral vector (AAV) gene therapy delivered via a one-time subretinal injection. This means that a small virus, that doesn’t cause illness in humans, is used as a delivery system to introduce or alter genetic material within cells. SPVN06 provides copies of a gene that aids survival of the cone photoreceptors responsible for central vision.
Rod photoreceptor cells naturally produce a neurotrophic factor, which is a type of protein that helps cells survive. This neurotrophic factor, known as RdCVF, helps cone photoreceptors to get the energy they need to stay healthy. When rod photoreceptors degenerate in RP, it means that cones do not receive RdCVF and start to degenerate too.
SPVN06 looks to restore RdCVF and promote an antioxidant known as RdCVFL which also protects cone cells from oxidative stress. RdCVF will be produced in the retinal pigment epithelium (RPE), the layer of cells that support photoreceptors, and RdCVFL will be produced directly within cone cells.
SPVN06 is expected to provide a long-lasting neuroprotective effect to prevent the progression of RP in individuals at a moderate to severe stage of the condition, reducing the loss of central vision.
SparingVision also have another treatment in development, SPVN20, designed to target dormant (non-functioning) cones in individuals with RP, and as such improve visual acuity and colour detection. SparingVision are looking at combining SPVN06 and SPVN20 into one therapy in the future to potentially treat various disease stages.
The trial:
The phase 1/2 PRODYGY trial is a multicentre, open-label dose escalation and controlled extension trial. This means that both participants and researchers are aware of the dose/treatment given.
The trial aims to evaluate the safety, tolerability and early efficacy of SPVN06 with RP due to mutations in RHO, PDE6A, or PDE6B genes. It involves 33 adults, with 27 receiving the treatment into their worst-seeing eye and 6 remaining untreated as part of a control group. The trial is being conducted in 2 stages:
- Stage 1 involved 9 participants receiving escalating doses of SPVN06 (3 = low, 3 = medium, 3 = high). Safety data showed a favourable tolerability profile allowing for progression to stage 2.
- Stage 2 involves 24 participants receiving either the high (9) or medium (9) dose or no injection (6) with a minimum of 12-month follow-up.
Initial data read-out is expected in 2027 after the 12-month follow-up period.
If you want to learn more about SparingVision, please visit their website here, or if you want to learn more about the trial itself, please click here.
If you want to read more about SPVN20, please visit our article