FDA Grants Rare Pediatric Disease Designation to QRX003 for Netherton Syndrome

Image Credit: © Maria Sbytova - stock.adobe.com

Earlier this week, the US Food and Drug Administration (FDA) granted Rare Pediatric Disease (RPD) Designation to Quoin Pharmaceuticals’ QRX003 for the treatment of Netherton Syndrome.¹ If a New Drug Application (NDA) for QRX003 is approved, Quoin may be eligible to receive a Priority Review Voucher (PRV), bringing the company one step closer to developing the first FDA-approved treatment for Netherton Syndrome. The European Medicines Agency (EMA) also granted Orphan Drug Designation to QRX003 earlier this year.

“We are very pleased to announce the receipt of Rare Pediatric Disease Designation for QRX003 for Netherton Syndrome, a severe and underserved genetic disease. The Quoin team is fully focused on completing our pivotal clinical studies and advancing QRX003 towards a New Drug Application as the first potential treatment for this terrible disease. We are highly encouraged by the promising efficacy data and clean safety profile seen to date,” Michael Myers, PhD, Chief Executive Officer of the company, said in a statement.¹

Netherton Syndrome is a severe, autosomal recessive genetic skin disorder caused by mutations in the SPINK5 gene. This results in a deficiency of LEKTI, a serine protease inhibitor, leading to unregulated kallikrein activity and subsequent skin barrier dysfunction, excessive desquamation, chronic inflammation, and debilitating pruritus.

QRX003 is a topical lotion containing a broad-spectrum serine protease inhibitor and is designed to inhibit the kallikrein proteases implicated in Netherton Syndrome pathology. Initial data has shown the therapy’s ability to restore skin barrier integrity and mitigate key symptoms.

Earlier this year, Quoin shared positive whole-body data from the Investigator Pediatric Netherton Syndrome trial.² A pediatric patient using QRX003 saw an improved disease state with visually healed skin and no adverse effects after just 2 weeks of twice-daily application. At baseline, the participant had an average itch score of 5 and an Investigator’s Global Assessment (IGA) score of 7, on scales of 0-10. After 2 weeks of treatment, this was reduced to 1 and 1-2, respectively.

The patient was able to discontinue all previously used medications, including antihistamines, glucocorticoids, and antivirals, thanks to the success of QRX003. Additionally, no antibiotic therapy has been needed since treatment began. The participant is no longer experiencing issues with sleep and no adverse events have been reported thus far. Pruritus, which was previously described as “chronically debilitating,” is now “highly tolerable and non-intrusive.”

“We believe that these results indicate that QRX003 is directly targeting the root cause of the disease and has the potential to provide Netherton Syndrome patients with the opportunity to have lives essentially free from the ravages of this terrible disease,” Myers said. “As we continue with our plans to expand this study to include additional pediatric subjects in other countries who would also receive whole body application of QRX003, we believe that the highly encouraging nature of the results generated to date for this patient could potentially bring hope and comfort to children and families whose lives are being so dramatically impacted by the consequences of this cruel disease.”²

References

1. Quoin Pharmaceuticals Announces FDA Grants Rare Pediatric Disease Designation for QRX003 in Netherton Syndrome. News release. Global Newswire. June 24, 2025. Accessed June 27, 2025. https://www.globenewswire.com/news-release/2025/06/24/3104239/0/en/Quoin-Pharmaceuticals-Announces-FDA-Grants-Rare-Pediatric-Disease-Designation-for-QRX003-in-Netherton-Syndrome.html

2. Quoin Pharmaceuticals Announces Highly Positive ‘Whole Body’ Clinical Data from Ongoing Pediatric Netherton Syndrome Study. News release. Globe Newswire. February 27, 2025. Accessed June 27, 2025. https://www.globenewswire.com/news-release/2025/02/27/3033744/0/en/Quoin-Pharmaceuticals-Announces-Highly-Positive-Whole-Body-Clinical-Data-from-Ongoing-Pediatric-Netherton-Syndrome-Study.html