Investigational RNA therapy Ultevursen for USH2A mediated retinitis pigmentosa & Usher syndrome

Picture that shows the eye and ear of a man

Ultevursen (previously named QR-421a) is an investigational RNA therapy that aims to stop vision loss in people with retinitis pigmentosa (RP) and Usher syndrome due to mutation(s) in a specific part of the USH2A gene, called exon 13.

Ultevursen (QR-421a)

Disease
USH2A mediated retinitis pigmentosa and Usher syndrome

Ultevursen (QR-421a) is an RNA therapy that aims to stop vision loss in retinitis pigmentosa (RP) and Usher syndrome type 2 due to mutations in exon 13 of the USH2A gene.

How does ultevursen work?

Ultevursen aims to stop vision loss in people with Usher syndrome and retinitis pigmentosa due to mutation(s) in exon 13 of the USH2A gene. Mutations in exon 13 are a common cause of these conditions. The mutations cause a mistake in the USH2A RNA and therefore the cell cannot use the RNA to produce a working USH2A protein that is essential for vision. 

Ultevursen works by binding to the mutated USH2A RNA and exclude exon 13 from the RNA. This approach is known as exon skipping. The cells in the retina can then produce a slightly shorter but functional USH2A protein.

Genetic testing

To know what mutation is causing RP or Usher, genetic testing is necessary. Genetic testing is the only way to receive an accurate diagnosis and will help find out if there are treatments or clinical trials available.

Internal link Learn about genetic testing
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Ultevursen clinical trials

Results from the Phase 1/2 Stellar trial were positive with ultevursen showing a concordant benefit in multiple measures of vision. Ultevursen was also observed to be well tolerated. In parallel to completing this Phase 1/2 trial a Phase 2/3 clinical trial is ongoing for this program to confirm ultevursen is safe and leads to better vision.

Learn more about clinical trials and why you should consider participating.

Sirius study - Phase 2/3 clinical trial

Ongoing, recruiting

Sirius logo

Sirius is a clinical trial of ultevursen (QR-421a) in adults and children (age 12 and up) with Usher syndrome and retinitis pigmentosa (RP) due to mutation(s) in exon 13 of the USH2A gene. In total 81 participants will receive intravitreal (into the eye) injections of ultevursen or a sham-procedure (simulated intravitreal procedure but no study medicine administered).

More about Sirius

Phase 1/2 clinical trial

Results from Stellar, a Phase 1/2 clinical trial of ultevursen (QR-421a), suggested the single injection with ultevursen was well tolerated with no serious adverse events reported. The Stellar study also showed benefit in the treated eye in comparison to the untreated eye across multiple eye tests. We have seen this benefit across all participants in the Stellar study.

More on Stellar results

Designations granted to ultevursen by authorities

  • FDA orphan drug designation
  • EMA orphan drug designation
  • FDA fast track designation 
  • FDA rare pediatric disease designation

Latest ultevursen press releases

Internal link More press releases
Female scientist working in the lab

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