Hellerup, Denmark, June 4, 2024 – UNION therapeutics A/S (UNION), a privately held, clinical stage, pharmaceutical development company focused on immunology, today announces successful completion of the ADESOS Phase 2b, randomized, dose-finding study evaluating orismilast as an oral treatment in 233 patients with moderate-to-severe AD.


Topline results from the ADESOS study have been selected for an oral presentation by the Signatory Investigator, Professor Jonathan Silverberg, MD, PhD, MPH at the late breaking research sessions at Revolutionizing Alopecia Areata, Vitiligo, and Eczema (RAVE) Conference on June 8-10, 2024, in Chicago, United States. It will be the first presentation of data from the ADESOS study.


Presentation details

Presentation: Efficacy and safety of orismilast, a potent PDE4B/D inhibitor, in adults with moderate-to-severe atopic dermatitis: a Phase 2b randomized, double-blind, placebo-controlled clinical trial (ADESOS)

Presenter: Jonathan Silverberg, MD, PhD, MPH, Professor of Dermatology at The George Washington University School of Medicine and Health Sciences and Signatory Investigator for ADESOS

Date and time: Monday June 10, 2024, at 1:30 PM – 4:40 PM CDT.


Jonathan Silverberg, MD, PhD, MPH, Professor of Dermatology at The George Washington University School of Medicine and Health Sciences and Signatory Investigator for ADESOS study said: 

“AD is one of the most common chronic inflammatory skin diseases worldwide. Innovation in recent years has brought good injectable treatments to patients, but a significant unmet medical need for a safe and effective oral treatment still exists. Orismilast offers the potential for a safe oral treatment with early itch reduction and holds a significant promise as a novel treatment option in AD.”


Kim Kjøller, Co-Chief Executive Officer of UNION therapeutics adds:

“The results from the ADESOS study with orismilast in atopic dermatitis (AD) follows positive read outs in psoriasis and hidradenitis suppurativa (HS) confirming the potential of orismilast as a safe oral treatment across immunology. We are pleased that the Phase 2b results from the ADESOS study have been selected for an oral presentation at the RAVE Conference in Chicago and look forward to the results being shared and discussed with the leading experts in the field.”


Orismilast is developed as a next-generation, high potency PDE4B/D selective inhibitor targeting first-in-class positions in AD and hidradenitis suppurativa (HS), and best in class in psoriasis. The efficacy and safety profile of orismilast have been evaluated in the previously reported IASOS Phase 2b study in psoriasis and OSIRIS Phase 2 study in HS. Data of these studies has been presented at leading scientific conferences and data is published in peer-reviewed journals, including the Journal of American Academy of Dermatology (JAAD) and the Journal of European Academy of Dermatology and Venerology (JEADV).

UNION has scheduled an End of Phase 2 meeting with the FDA to discuss advancing the orismilast development program into Phase 3 studies in AD.  

About the ADESOS Phase 2b study

The Phase 2b study was a randomized, double-blind, placebo-controlled, parallel-group, dose-finding study to evaluate the efficacy and safety of orismilast in patients with moderate to severe AD. The study included 233 patients who were randomized to three active doses (20mg, 30mg, and 40 mg) of orismilast or placebo administered twice daily. The study was conducted in centers in Europe and in the US.

About orismilast

Orismilast is a next generation, high potency PDE4 inhibitor targeting the PDE4B/D subtypes linked to inflammation, demonstrating potent inhibition of Th1, Th2 and Th17 pathways. It acts early in the inflammation cascade, inducing a broad range of anti-inflammatory effects across multiple cytokines involved in many dermatological and immunological diseases.1)

UNION is developing orismilast as an oral treatment, based on the well-known safety profile of the PDE4 class, across immunology, initially targeting best-in-class or first-in-class positions in atopic dermatitis (AD), hidradenitis suppurativa (HS), psoriasis and ulcerative colitis (UC).

The FDA has cleared UNION’s Investigational New Drug (IND) application for orismilast and granted Fast Track designation for orismilast for the treatment of moderate to severe AD as well as for the treatment of moderate to severe HS.

About atopic dermatitis

AD is a chronic inflammatory skin disease affecting 2.1-4.9 % of the adult population worldwide and is the most common skin disease among children.2) There were approximately 20 million diagnosed moderate-to-severe adult patients with AD in 2023 in the Seven Major Markets (United States, France, Germany, Italy, Spain, UK, and Japan).3) Disease symptoms are characterized by recurrent eczematous skin lesions and intense itch. AD has a substantial psychosocial impact on patients and relatives.4) During disease flares, approximately 80% of patients may experience disturbed sleep, which may also disrupt the sleep of family members.5) The disease also appears to impact the mood and patients have an increased risk of anxiety and depression.6)


1)       Blauvelt A et al., Dermatology and Therapy 2023: Next Generation PDE4 Inhibitors that Selectively Target PDE4B/D Subtypes: A Narrative Review – PubMed (nih.gov) &

Silverberg J.I. et al., JEADV 2022: https://onlinelibrary.wiley.com/doi/10.1111/jdv.18818  &

Warren R.B. et al., JEADV 2022: https://onlinelibrary.wiley.com/doi/10.1111/jdv.18812

2)       Barbarot S et al,. Allergy 2018: https://pubmed.ncbi.nlm.nih.gov/29319189/ https://pubmed.ncbi.nlm.nih.gov/25925336/

3)       EvaluatePharma 2023

4)       Laughter MR et al., British Journal of Dermatology 2021: https://pubmed.ncbi.nlm.nih.gov/33006135/

5)       Eichenfield LF et al., Journal of the American Academy of Dermatology 2014: https://pubmed.ncbi.nlm.nih.gov/24290431/

6)       Drucker AM et al., The Journal of Investigative Dermatology 2017: https://pubmed.ncbi.nlm.nih.gov/27616422/



Morten Boesen, Chief Financial Officer, UNION therapeutics A/S

+45 2381 5487

[email protected]


Sarah Toft-Jørgensen, Director of Communications and IR, UNION therapeutics A/S

+45 5385 3044

[email protected]


About UNION therapeutics

UNION therapeutics is a privately held, clinical stage, pharmaceutical development company focused on immunology. UNION is headquartered in Hellerup, Denmark, and led by an international team combining biotech entrepreneurs and seasoned pharma executives, with a track record of developing and launching more than fifteen marketed drugs. Read more at http://www.uniontherapeutics.com