UNION therapeutics (Union) has enrolled the first subject in the Phase IIb ADESOS clinical trial of the orismilast MR tablet in moderate to severe atopic dermatitis (AD) adult patients.

The randomised, placebo-controlled, double-blind, parallel-group, dose-finding trial will analyse the safety and efficacy of orismilast in these patients to detect a suitable dosing regimen for Phase III trials.

It will enrol 210 subjects who will be categorised to receive twice-a-day doses of either 20mg, 30mg or 40mg of orismilast versus placebo. 

The company plans to carry out the trial in centres in Europe and the US.

An inhibitor of phosphodiesterase type-4 (PDE4), orismilast is claimed to work early in the inflammation cascade to elicit a wide spectrum of downstream anti-inflammatory effects. 

Orismilast can potentially hinder several inflammatory pathways linked to dermatological and immunological ailments and become a safe treatment option for such diseases.

The company has two product candidates with orismilast in its clinical stage pipeline, notably orismilast MR tablet and topical orismilast.

Apart from AD, orismilast MR tablet is being analysed to treat psoriasis and hidradenitis suppurativa (HS) while topical orismilast has clinical proof of concept validated in AD. 

Union signed a strategic collaboration and licensing agreement with Innovent Biologic in September 2021 for orismilast in Hong Kong, Mainland China, Macau and Taiwan.

Last November, orismilast MR tablet received Fast Track designation from the US Food and Drug Administration to treat moderate to severe AD.

Union CEO Kim Kjøller said: “Orismilast modified release tablet holds the potential to become a first-in-class treatment and become an efficacious treatment option for patients who need systemic therapy for atopic dermatitis. 

“The initiation of the ADESOS study marks an important advancement of Union’s pipeline.”

At the beginning of this year, the company enrolled the first subject in the IASOS Phase IIb trial of oral orismilast in psoriasis patients.