Quoin Pharmaceuticals Ltd. (“Quoin” or the “Company”), a late clinical-stage specialty pharmaceutical company focused on rare and orphan diseases, announced positive interim results from CL-QRX003-004, its ongoing Phase 2/3 study of QRX003 4% lotion in patients with Netherton Syndrome.

Summary of CL-QRX003-004 Interim Results in Netherton Syndrome

• The primary endpoint of 1-grade improvement or greater for IGA on all of the treatment area met the pre-specified alpha-adjustment for interim analysis with statistical significance (p= 0.0087 vs. α=0.0215.) Four of six (66.7%) participants achieved the target 1-grade or greater improvement across all of the treatment area in Investigator Global Assessment (IGA) from baseline at Week 12, or 66.67% (95% CI: 22.28%, 95.67%), p=0.0087 against a pre-specified alpha of 0.0215.
• Two of those four (50%) participants achieved a 2-grade or greater IGA improvement across all of the treatment area.
• Key secondary endpoint, a Global Statistical Test of Global Impression of Change, achieved statistical significance at week 12 with a mean change of -1.5 (SD 0.82), (p-value=0.007 vs α=0.0215.) All three participants with moderate to severe pruritus at baseline achieved a clinically meaningful greater than 3-grade improvement in Worst Itch Numeric Rating Scale (WI-NRS, scale 0-10) at Week 12. One participant had a greater than 6-grade improvement.
• For the Ichthyosis Area and Severity Index (IASI), improvements ranging from 31-87% reduction in severity from baseline were recorded after 12 weeks of treatment with QRX003. These results mirrored those for the IGA with the same 4 participants recording clinically meaningful improvements for both endpoints.
• No treatment-related serious adverse events were reported. No clinically significant ECG, laboratory, or vital sign abnormalities were identified.
• Quoin expects to complete recruitment of all 20 participants in CL-QRX003-004 by the end of 2026 and report topline data in the second quarter of 2027.
• If approved, QRX003 could become the first FDA-approved treatment for Netherton Syndrome.

Study Design

CL-QRX003-004 is a Phase 2/3, multicenter, baseline-controlled, open-label study evaluating the safety, tolerability, and efficacy of QRX003 4% lotion applied twice daily to all of the body excluding the scalp in patients with Netherton Syndrome. The study will enroll approximately 20 evaluable participants aged four years and older across multiple clinical sites in both the US and the UK.

Treatment duration is 12 weeks, followed by a four-week post-treatment End of Study visit. Subjects must discontinue all standard of care therapy, including topical and systemic prescriptions, for the duration of the study.