Usher Syndrome Research News

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Published June 2022

Presented by David Corey, PhD, to the World Medical Innovation Forum 2022, the results of the lab’s work with collaborators in the creation of a “mini-PCDH15” gene. This mini-gene, which can fit into a standard single AAV vector, was used to deliver a functional mini-PCDH15 gene into the inner ears of new born mice that are deaf like Usher 1F patients. Results after 4 weeks showed these mice retained most of their hearing, while the hearing of untreated USH1F-mice degenerated. It’s hoped, “if gene therapy with mini-PCDH15 works in the demanding environment of the inner ear, it is likely to also work to prevent the progressive blindness”. Read more here. 

Published June 2022

Work presented by Maryna Ivanchenko and team at the David Corey’s Lab to the 2022 ARVO Annual Meeting, showed success of their dual-AAV delivering a functional copy of the gene PCDH15 to mice model of USH1F thus overcoming hurdles with the size of this gene, which is too large for a single AAV. Results showed that most hearing was restored in a mouse model of USH1F, and mediates expression and normal localization of PCDH15 in human photoreceptors in vitro. Read more here. 

Published 09 May 2022

Presented at ARVO 2022, Prof Martha Neuringer and her team at OHSU announced they have successfully created the first genetically edited non-human primate model of USH1B, the first ever of its kind. Named Gemma, she brings hope for potential USH1B therapies as animal models are needed to test potential therapies such as dual-AAV gene therapy, before they can proceed with clinical trials in humans. Read more here. 

Published May 2022

Results from this proof-of-concept study, using optogentic gene therapy targeting cone photoreceptors (instead of cells in the inner retina or the retinal ganglion cells), showed successful improvement in vision in a large animal model. The subretinal delivery and expression of the optogenetic molecule in cone photoreceptors was also deemed well tolerated and safe. These positive findings presented in this paper supports that further studies should be carried out to evaluate the safety and efficacy of cone photoreceptor-directed optogenetic therapy for people with RP. Such studies could be carried out in conjunction with image intensifiers (i.e., goggles) that deliver the appropriate light stimuli to the treated eye. Read the full paper here. 

Published: 07 December 2021

A recent paper reveals findings from a study on USH1 that may alter our current views that USH1 is a degenerative condition affecting the photoreceptors by suggesting that instead, photoreceptors may have originally developed abnormally and worsened over time as the eye matured. This discovery may potentially lead to a new approach in USH1 research focusing on therapies to provide early treatment to stabilise “OS biogenesis” before widespread death, instead of, as most current research, focusing on the replacement of lost photoreceptors. Read the full paper here.

Announced: 12 April 2022

ProQR has recently dosed its first patients in the UK in its phase 2 /3 Sirius trial for people with retinitis pigmentosa and Usher syndrome due to mutations in exon 13 of the USH2A gene. In this phase of the Sirius trial, the safety and efficacy of the investigational RNA therapy Ultevursen is being investigated, with ProQR hoping the drug will be successful in halting against further vision loss. If you wish to learn more about this trial, please visit ProQR's website here 

Published: 28 February 2022

Findings from a recent study confirms that ARSG variants cause the newly defined USH type 4 and supports the proposed extension of the phenotypic USH classification. It appears that this type may cause a late-onset of symptoms, as all of the subjects (from Ireland, Germany, and the Netherlands) in this study experienced a late-onset of hearing loss (SNHL) and retinitis pigmentosa (RP). Read the full the paper here.