Retinitis Pigmentosa Research Advances

FDA APPROVES SPARK’S VISION-RESTORING GENE THERAPY

Spark Therapeutics’ vision-restoring RPE65 gene therapy has received marketing approval from the U.S. Food and Drug Administration, becoming the first gene therapy to gain regulatory approval in the U.S. for the eye or any inherited condition. Known as LUXTURNA™ (voretigene neparvovec), the gene therapy restored vision in a clinical trial for people between the ages of 4 and 44 with Leber congenital amaurosis (LCA) caused by mutations in the gene RPE65. Study participants with severe vision loss reported putting away their navigational canes, seeing stars, being able to read, and recognizing faces of loved ones. Vision restoration has persisted for at least three years. The treatment is also designed to work for people with retinitis pigmentosa (RP) caused by RPE65 mutations. The Foundation invested about $10 million in more than a decade of lab research that made possible the RPE65 gene therapy clinical trial at the Children’s Hospital of Philadelphia (CHOP).

 

THREE COMPANIES ARE CONDUCTING CLINICAL TRIALS FOR THEIR OPTOGENETIC THERAPIES FOR ADVANCED RP

GenSight, Bionic Sight, and Nanoscope have each launched clinical trials for their optogenetic therapies for RP and potentially other retinal diseases. The treatments are designed to provide vision to people who are completely blind from conditions such as retinitis pigmentosa and Usher syndrome. GenSight and Bionic Sight are designed to work by bestowing light sensitivity to ganglion cells in patients who have lost all of their photoreceptors. Nanoscope is targeting bipolar cells. All three companies have reported some modest restored vision in their early stage trials.

 

KIORA REPORTS VISION RESTORATION IN PHASE 1/2 CLINICAL TRIAL FOR PHOTOSWITCH THERAPY

Kiora Pharmaceuticals has announced some vision restoration for participants in ABACUS-1, its Phase 1/2 clinical trial in Australia for KIO-301, a molecule designed to bestow light sensitivity to retinal ganglion cells in people with advanced retinitis pigmentosa (RP) and other retinal diseases. Known as a photoswitch, the molecule enables retinal ganglion cells to respond to light, thereby working like a back-up system for lost photoreceptors. Retinal ganglion cells, which are downstream from photoreceptors, often survive in advanced retinal disease but don’t naturally respond to light.

 

JOHNSON & JOHNSON, BEACON, AND 4DMT CONDUCTING XLRP GENE THERAPY CLINICAL TRIALS

Three companies are each conducting XLRP (RPGR) gene therapy clinical trials. J&J is in Phase 3 and Beacon is in Phase 2 and planning its Phase 3 trial. Both companies have reported vision improvements (retinal sensitivity and/or visual acuity) for patients in their Phase 1/2 trials. 4DMT is conducting a Phase 1/2 XLRP gene therapy clinical trial.

 

COAVE CONDUCTING GENE THERAPY CLINICAL TRIAL FOR RP (PDE6B MUTATIONS)

The French biotech CoaveTherapeutics reported encouraging 24-month results for 17 adult patients in its Phase 1/2 PDE6B gene therapy clinical trial underway at Clinique Ophthalmologique, CHU de Nantes, in France. Vision improvements in the trial were observed for patients who received the high and low dose of the gene therapy, which is known as HORA-PDE6B. Five-year follow-up data showed that vision in patients receiving the low dose treatment had stable best-corrected visual acuity (BCVA). In comparison, BCVA consistently declined in untreated eyes. A full-field stimulation test using blue light indicated that rod function also improved in patients' treated eyes. The company is also evaluating its HORA-PDE6B gene therapy in as many as six younger patients, 13 to 17 years old, who have earlier stage disease. Three younger patients are enrolled thus far.

 

PHASE 3 CLINICAL TRIAL OF NAC LAUNCHED FOR RP PATIENTS

Johns Hopkins University (JHU) has launched a Phase 3 clinical trial of N-acetylcysteine (NAC) for the treatment of retinitis pigmentosa (RP). Known as NAC Attack, the 45-month study is enrolling approximately 438 patients at 30 sites throughout the US, Canada, Mexico, and Europe. Study participants will be assigned randomly 2:1 to either the treatment or placebo group, respectively. If the NAC group shows benefit (i.e., slowing of vision loss) at 21 months, participants in the placebo group will begin to receive the treatment.JHU’s Peter Campochiaro, MD, and Xiangrong Kong, PhD, designed the trial and are its lead investigators. The National Eye Institute is providing more than $20 million in funding for NAC Attack. NAC is an oral antioxidant approved in 1963 by the US Food & Drug Administration for acetaminophen (Tylenol®) overdose. It is also used for treating cystic fibrosis and pulmonary diseases.

 

NACUITY CONDUCTING CLINICAL TRIAL FOR ORAL ANTIOXIDANT THERAPY

Dallas-based Nacuity is conducting a Phase 1/2 clinical trial in Australia for its oral antioxidant therapy. The trial is for people with Usher syndrome (retinitis pigmentosa with hearing loss). The Foundation Fighting Blindness is investing up to $7.5 million to advance the promising, emerging drug for retinitis pigmentosa, Usher syndrome, and related conditions. Known as N-acetylcysteine-amide (NACA), the molecule is designed to slow vision loss by protecting retinal cells from oxidative stress. In previous Foundation-funded lab studies at Johns Hopkins University, NACA slowed retinal degeneration in rodent models of RP. Johns Hopkins and the National Eye Institute are also launching an international Phase 3 clinical trial for NACA – the original formulation of N-acetylcystieine.

 

SPARINGVISION LAUNCHES CLINICAL TRIAL TO EVALUATE SIGHT-SAVING PROTEIN FOR RP

SparingVision has launched a Phase 1/2 clinical trial for its emerging therapy to preserve cone-mediated vision at the University of Pittsburgh Medical Center. A spin-off of the Institut de la Vision, SparingVision was established to clinically develop and commercialize a protein known as rod-derived cone-viability factor (RdCVF). The emerging therapy performed well in several previous lab studies funded by the Foundation Fighting Blindness. Scientists demonstrated that RdCVF prevented or slowed the degeneration of cones, the cells in the retina that provide central and color vision and enable people to read, drive, and recognize faces. RdCVF is naturally secreted by rods, the retinal cells that provide night and peripheral vision.

 

OCUGEN HAS LAUNCHED A PHASE 3 CLINICAL TRIAL FOR ITS MODIFIER GENE THERAPY

The biotech company Ocugen has launched a Phase 3 clinical trial for its gene-agnostic, modifier gene therapy under development for people with retinitis pigmentosa (RP). The trial will enroll approximately 150 participants at 15 sites in the US. One arm of the trial will enroll 75 participants with mutations in the RHO gene. The other arm will enroll 75 participants with mutations in other genes causing RP. In each arm, participants will be randomized 2:1 to treatment and untreated control groups, respectively. OCU400 is a one-time therapy injected underneath the retina to deliver copies of the NR2E3 gene to improve regulation of multiple functions in the retina including: photoreceptor maintenance and development, metabolism, phototransduction, inflammation, and cell survival. OCU400 uses a human-engineered, adeno-associated virus (AAV), which works like a container system, to deliver NR2E3 copies into the recipients’ photoreceptors.

 

THÉA LAUNCHES SEPUL BIO TO ADVANCE LCA10 AND USH2A RNA (ANTISENSE OLIGONUCLEOTIDE) THERAPY

Théa has launched a new business unit, Sepul Bio, to continue clinical development of two RNA therapies: sepofarsen for people with LCA10 caused by the IVS26 mutation in the CEP290 gene, and ultevursen for people with exon 13 mutations in the USH2A gene. Both therapies, originally developed by ProQR, had shown efficacy in clinical trials. ProQR made a business decision to leave the ophthalmology space and subsequently licensed sepofarsen and ultevursen to Théa.

 

 

JULY 2024