• General Dermatology
  • Eczema
  • Alopecia
  • Aesthetics
  • Vitiligo
  • COVID-19
  • Actinic Keratosis
  • Precision Medicine and Biologics
  • Rare Disease
  • Wound Care
  • Rosacea
  • Psoriasis
  • Psoriatic Arthritis
  • Atopic Dermatitis
  • Melasma
  • NP and PA
  • Anti-Aging
  • Skin Cancer
  • Hidradenitis Suppurativa
  • Drug Watch
  • Pigmentary Disorders
  • Acne
  • Pediatric Dermatology
  • Practice Management

Oral Orismilast Shows Clinically Relevant Improvement In Patients With Moderate To Severe Hidradenitis Suppurativa


The OSIRIS open-label study resulted in a reduction of pain and improvement in quality of life for participants.

In a study of individuals with moderate to severe hidradenitis suppurativa (HS), treatment with oral orismilast showed clinically relevant improvements. Orismilast is a high-potency, next generation PDE4 inhibitor that targets the PDE4 subtypes linked to inflammation.1



The 16-week study resulted in a reduction of pain, (Global Pain Assessment)and improvement in patient-reported quality of life (DLQI). Participants had experienced several prior failures on other biologics treatments.

Orismilast operates early in the inflammation cascade, prompting a broad range of anti-inflammatory effects across a number of cytokines involved in several dermatological and immunological diseases.

The OSIRIS open-label, single-center, prospective, single-arm, investigator-initiated proof-of-concept study evaluated safety, efficacy, and tolerability of oral orismilast taken twice a day for up to 16 weeks.

Gregor Jemec, professor, department of dermatology, Zealand, University Hospital, Roskilde, Denmark, told Dermatology Times®, “The apparent effects at low doses, and the ability to control the adverse effect by reducing the dose was very impressive. It has been a good beginning full of promise and hope.” He added, “Biologic therapies are generously being introduced in HS management these years, in response to an unmet need for effective treatment. Their very specific mode of actions, typically targeting one specific cytokine almost create ‘knock-out patients’ and thereby provide important insight into the pathophysiology of the disease. This trial suggests that a broader blocking of inflammatory pathways is clinically relevant.”

In the US there is currently only 1 FDA approved drug, a biologic, to treat moderate to severe HS and no approved treatment for mild cases. Although off-label, topical, oral, and intravenous antibiotics are used for HS management, the effectiveness is usually temporary.

UNION therapeutics A/S (UNION) announced that orismilast has been given a Fast Track designation by the FDA for HS and UNION plans to ask the FDA’s advice for design of the pivotal study program.

In addition to being given Fast Track designation for HS, orismilast has also been granted Fast Track designation in the treatment of moderate to severe atopic dermatitis (AD).

“The results are very encouraging, including not least seeing patients in this difficult to treat patient population achieving HiSCR90 and HiSCR100 response. Equally important, patients experienced significant reduction in pain, which is a great burden for patients with HS, and most responders had moderate or severe HS at baseline, including several prior failures to biologics treatment. The study supports the target product profile of orismilast as a high-potency PDE4 inhibitor consistent with the recent IASOS Phase 2b study in psoriasis,” said Kim Kjøller, chief executive officer, UNION therapeutics.


  1. UNION therapeutics announces positive topline results from the OSIRIS investigator-initiated proof-of-concept study of oral orismilast in patients with hidradenitis suppurativa. News Release. Union therapeutics. June 21, 2023. Accessed June 22, 2023. https://uniontherapeutics.com/union-therapeutics-announces-positive-topline-results-from-the-osiris-investigator-initiated-proof-of-concept-study-of-oral-orismilast-in-patients-with-hidradenitis-suppurativa/ 
Related Videos
© 2024 MJH Life Sciences

All rights reserved.