Quoin Submits First-Ever IND Application for Peeling Skin Syndrome Therapy

Quoin Pharmaceuticals has submitted an Investigational New Drug (IND) application to the US Food and Drug Administration for QRX003 as a potential treatment for peeling skin syndrome (PSS), marking the first IND submission specifically for this rare dermatologic disorder.¹

The company has already shared initial clinical data from an ongoing investigator-led pediatric study of the drug that supports the submission. Skin healing was observed in a single patient after just 12 weeks of treatment with substantial reductions in the Modified Ichthyosis Area of Severity Index, the Investigator’s Global Assessment, and the Children’s Dermatology Life Quality Index.² The patient has been treated for over 15 months with no adverse events.

The submission represents an important milestone for a disease that currently has no approved treatments or cure. Pending FDA review, Quoin plans to initiate a phase 2 clinical study during the second half of 2026. It will recruit 6 to 8 pediatric and adult participants in the US and Europe.

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“This IND submission represents yet another significant milestone for Quoin. With QRX003 now advancing toward formal clinical development in a second rare disease indication, we believe it further underscores its versatility as a platform for the potential treatment for a number of such diseases,” CEO Michael Myers, PhD, said in the press release. “Quoin was the first company to submit an IND for Netherton syndrome and we are excited to follow that up with another first IND submission, further illustrating our leadership position in this space.”¹

PSS is a rare autosomal recessive genodermatosis caused by loss-of-function variants in the corneodesmosin (CDSN) gene. The disorder results in excessive shedding of the superficial layers of the epidermis and is associated with significant patient burden, including severe pain and chronic pruritus. Currently, management is limited largely to symptomatic approaches such as over-the-counter emollients. There is currently no cure or FDA-approved treatment.

QRX003 is a topical investigational lotion containing a broad-spectrum serine protease inhibitor. Designed to inhibit the kallikrein proteases implicated in Netherton Syndrome pathology, QRX003 aims to restore skin barrier integrity and mitigate key symptoms. Early clinical data demonstrated encouraging therapeutic activity, including rapid and sustained skin healing, resolution of pruritus, and elimination of night-time sleep disturbances.

The PSS program represents the second dermatologic indication being pursued for QRX003. The investigational therapy is already under development for Netherton syndrome, another rare inherited skin disorder characterized by skin barrier dysfunction and inflammation. In March 2026, the FDA granted Fast Track designation to QRX003 lotion (4%) for the treatment of this rare disease.³

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The company also indicated that it expects a busy clinical development period in the second half of 2026. In addition to advancing QRX003, Quoin is planning clinical testing of QRX009, its topical rapamycin platform for the treatment of microcystic lymphatic malformations, venous malformations, and angiofibromas, during the same timeframe. The formulations will use Quoin’s in-licensed proprietary Invisicare delivery technology, which works to optimize the mTOR inhibitor of rapamycin and penetrate deep into the dermis to boost clinical and therapeutic efficacy in all orphan rare skin diseases.

“With these assets, we are rapidly building what we believe is becoming one of the most robust and commercially valuable pipelines in the rare dermatology space,” Myers concluded.¹

References

1. Quoin Pharmaceuticals Submits IND Application for QRX003 in Peeling Skin Syndrome. News release. Globe Newswire. June 2, 2026. Accessed June 2, 2026. https://www.globenewswire.com/news-release/2026/06/02/3305172/0/en/quoin-pharmaceuticals-submits-ind-application-for-qrx003-in-peeling-skin-syndrome.html

2. Quoin Pharmaceuticals Announces Initial Positive Clinical Data for QRX003 from Pediatric Peeling Skin Syndrome Study. News release. Globe Newswire. May 14, 2025. Accessed June 2, 2026. https://www.globenewswire.com/news-release/2025/05/14/3081028/0/en/Quoin-Pharmaceuticals-Announces-Initial-Positive-Clinical-Data-for-QRX003-from-Pediatric-Peeling-Skin-Syndrome-Study.html

3. Quoin Pharmaceuticals Announces FDA Grants Fast Track Designation for QRX003 for the Treatment of Netherton Syndrome. News release. Globe Newswire. March 11, 2026. Accessed June 2, 2026. https://www.globenewswire.com/news-release/2026/03/11/3253756/0/en/Quoin-Pharmaceuticals-Announces-FDA-Grants-Fast-Track-Designation-for-QRX003-for-the-Treatment-of-Netherton-Syndrome.html