SparingVision Launches Clinical Trial for Therapy to Re-Activate Dormant Cones in Advanced RP

SparingVision, a Paris-based company developing therapies for inherited retinal diseases (IRDs), has dosed the first patient in its NYRVANA Phase 1/2 clinical trial for SPVN20, a gene-agnostic gene therapy designed to restore cone vision for people with advanced retinitis pigmentosa (RP) and potentially other IRDs. The trial was initiated in Belgium and is expanding soon to France and Ireland. The company plans to seek clearance in 2026 to conduct the trial in the US.

The RD Fund, the Foundation’s venture philanthropy arm, is an original investor in SparingVision. The Foundation also provided significant funding to Deniz Dalkara, PhD, Institut de la Vision, for preclinical development of an approach similar to the one used in SPVN20.

The SPVN20 gene therapy is designed to re-activate dormant cones, i.e., cones that haven’t fully degenerated but have stopped providing visual function. Cones are the photoreceptors that provide visual acuity and color vision. Researchers have observed that many people with advanced RP, even those with low or no light perception, may have dormant cones that can be targeted by SPVN20.

The SPVN20 gene therapy is delivered by a one-time injection into the vitreous, the soft gel in the middle of the eye. The gene therapy uses an adeno-associated virus (AAV) to penetrate dormant cones with a gene that expresses a protein to establish a phototransduction cascade, a biochemical process that enables cones to convert light into electrical signals. The brain uses the signals to create the images we see. The protein is known as a G protein-gated inwardly rectifying potassium (GIRK) channel.

Researchers don’t believe SPVN20 will stop retinal degeneration. However, it could potentially be combined with a neuroprotective therapy such as SparingVision’s SPVN06, which is currently enrolling in the PRODYGY Phase 1/2 clinical trial in France and the US. SPVN06 expresses proteins designed to preserve cones.

SPVN20 is similar to but different from optogenetics. Current optogenetic approaches in clinical trials are gene-agnostic and designed to restore vision for people with advanced vision loss. Optogenetics works by expressing light-sensing proteins called opsins in ganglion or bipolar cells—cells that survive advanced retinal disease but normally don’t sense light.

SPVN20 doesn’t express a light-sensing opsin. Rather, it establishes a new channel that links to existing opsins in cones (dormant cones have functional opsins), so the phototransduction cascade can be re-established.

Optogenetics has restored meaningful vision, e.g., the ability to recognize shapes and objects. Researchers believe SPVN20 may provide even better visual acuity and color perception.

“The launch of a clinical trial that offers the promise of re-establishing sight regardless of the IRD genetic cause is a significant milestone for SparingVision and the RD Fund,” says Rusty Kelley, PhD, managing director, RD Fund. “This exciting and elegant approach offers more than hope to our affected community with advanced vision loss.”