Quoin Pharmaceuticals Submits IND Application for QRX003 in Peeling Skin Syndrome

-First ever IND submission for this disease, which has no current treatment or cure-

-Quoin plans Phase 2 study initiation in 2H 2026-

-Submission supported by positive initial clinical data from Investigator-led pediatric study-

-Second indication for QRX003, in addition to Netherton Syndrome-

ASHBURN, Va., June 02, 2026 (GLOBE NEWSWIRE) -- Quoin Pharmaceuticals Ltd. (NASDAQ:QNRX), a late clinical-stage specialty pharmaceutical company focused on rare and orphan diseases, today announced the submission of an Investigational New Drug (IND) application to the U.S. Food and Drug Administration (FDA) for QRX003 for the treatment of Peeling Skin Syndrome (PSS). Pending FDA review, Quoin expects to initiate a Phase 2 clinical study in the second half of 2026.

The IND submission is supported by clinical observations from Quoin's ongoing investigator-led pediatric PSS study. The initial subject has been treated with QRX003 for over 15 months and significant clinical improvements in skin, sleep patterns and overall quality of life have been achieved. QRX003 has been well tolerated, with no adverse events reported. The Phase 2 study is expected to recruit 6-8 pediatric and adult patients with PSS in both the US and Europe.

"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. 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," said Dr. Michael Myers, CEO of Quoin Pharmaceuticals. "We look forward to initiating the Phase 2 study and to continuing to expand the development of QRX003 across additional rare dermatologic indications. This is a very exciting time for Quoin, with both our QRX003 platform and our QRX009 topical rapamycin platform, targeted to be in clinical testing in the second half of this year. 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."

About Peeling Skin Syndrome (PSS)

Generalized inflammatory peeling skin syndrome (PSS) is a rare autosomal recessive genodermatosis caused by loss-of-function disease-causing variants of the corneodesmosin gene (CDSN), resulting in excessive shedding of the superficial layers of the epidermis. Patients generally suffer from a variety of conditions including severe pain and chronic pruritus (itch). There is currently no approved treatment for PSS, and patients try to manage symptoms using over-the-counter emollients.

About Quoin Pharmaceuticals Ltd.

Quoin Pharmaceuticals Ltd. is a late clinical-stage specialty pharmaceutical company focused on developing and commercializing therapeutic products that treat rare and orphan diseases. We are committed to addressing unmet medical needs for patients, their families, communities and care teams. Quoin's innovative pipeline is focused on two key platform products, QRX003 and QRX009, that collectively have the potential to target a broad number of rare and orphan indications, including Netherton Syndrome, Peeling Skin Syndrome, Palmoplantar Keratoderma, PC, GS, TSC, microcystic lymphatic malformations, venous malformations, angiofibromas and others. For more information, visit: www.quoinpharma.com or LinkedIn for updates.

Cautionary Note Regarding Forward Looking Statements

The Company cautions that statements in this press release that are not a description of historical facts are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements may be identified by the use of words referencing future events or circumstances such as "expect," "intend," "plan," "anticipate," "believe," "look forward to," and "will," among others. All statements that reflect the Company's expectations, assumptions, projections, beliefs, or opinions about the future, other than statements of historical fact, are forward-looking statements, including, without limitation, statements relating to: plans to initiate a Phase 2 clinical study for QRX003 for the treatment of PSS in the second half of 2026; recruiting 6-8 pediatric and adult patients with PSS in both the US and Europe; QRX003's versatility as a potential treatment for a number of rare diseases; continuing to expand the further development of QRX003 across additional rare dermatologic indications; the QRX003 platform and QRX009 platform being targeted to be in clinical testing in the second half of this year; rapidly building one of the most robust and commercially valuable pipelines in the rare dermatology space; and Quoin's belief that its products in development collectively have the potential to target a broad number of rare and orphan indications, including Netherton Syndrome, Peeling Skin Syndrome, Palmoplantar Keratoderma, PC, GS, TSC, microcystic lymphatic malformations, venous malformations, angiofibromas and others. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. These forward-looking statements are based upon the Company's current expectations and involve assumptions that may never materialize or may prove to be incorrect. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of various risks and uncertainties including, but not limited to, the Company's ability to pursue its regulatory strategy; the Company's ability to obtain regulatory approvals for commercialization of product candidates or to comply with ongoing regulatory requirements; the Company's ability to complete clinical trials on time and achieve desired results and benefits as expected; and other factors discussed in the Company's Annual Report on Form 10-K for the year ended December 31, 2025 and in other filings the Company has made and may make with the SEC in the future. One should not place undue reliance on these forward-looking statements, which speak only as of the date on which they were made. The Company undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made, except as may be required by law.

For further information, contact:

Quoin Pharmaceuticals Ltd.

Michael Myers, Ph.D., CEO

mmyers@quoinpharma.com

Investor Relations

PCG Advisory

Jeff Ramson

jramson@pcgadvisory.com

(646) 863-6341