The purpose of this trial is to compare the efficacy of treatment with LEO 90100 to that of treatment with vehicle for up to 4 weeks in subjects with psoriasis vulgaris.

Inclusion Criteria:

• A clinical diagnosis of psoriasis vulgaris of at least 6 months duration involving the trunk and/or limbs
• Psoriasis vulgaris on the trunk and/or limbs (excluding psoriasis on the genitals and skin folds) involving 2-30% of the Body Surface Area (BSA)
• An Investigator's Global Assessment of disease severity (IGA) of at least mild at Day 0 (Visit 1)
• A modified PASI (m-PASI) score of at least 2 at Day 0 (Visit 1)
• A target lesion of a minimum of 5 cm at its longest axis and preferably not located on the extensor surface on an elbow or knee, scoring at least 1 for each of redness, thickness and scaliness, and at least 4 in total by the Investigator's Assessment of Severity of the Target Lesion

Exclusion Criteria:

• Systemic treatment with biological therapies, whether marketed or not, with a possible effect on psoriasis vulgaris within the following time periods prior to randomisation:

  • etanercept - within 4 weeks prior to randomisation
  • adalimumab, infliximab - within 8 weeks prior to randomisation
  • ustekinumab - within 16 weeks prior to randomisation
  • other products - within 4 weeks/5 half-lives prior to randomisation (whichever is longer)

• Systemic treatment with all other therapies with a possible effect on psoriasis vulgaris (e.g., corticosteroids, retinoids, methotrexate, ciclosporin and other immunosuppressants) within 4 weeks prior to randomisation.

• Subjects who have received treatment with any nonmarketed drug substance (i.e. a drug which has not yet been made available for clinical use following registration) within 4 weeks/5 half-lives (whichever is longer) prior to randomisation.

• PUVA therapy within 4 weeks prior to randomisation.

• UVB therapy within 2 weeks prior to randomisation.

• Topical anti-psoriatic treatment on the trunk and limbs (except for emollients) within 2 weeks prior to randomisation.

• Topical treatment on the face, scalp and skin folds with corticosteroids, vitamin D analogues or prescription shampoos within 2 weeks prior to randomisation.

• Planned initiation of, or changes to, concomitant medication that could affect psoriasis vulgaris (e.g. beta blockers, antimalarial drugs, lithium, ACE inhibitors) during the trial.

• Current diagnosis of guttate, erythrodermic, exfoliative or pustular psoriasis.

• Previously randomised in this trial or any previously conducted trial of LEO 90100.