Clinical Trial to Assess Safety, Tolerability and the Pharmacodynamics Effect of Calcipotriol/Betamethasone Dipropionate in a New Administration Form in Subjects With Chronic Plaque Psoriasis.

Key Inclusion Criteria: * Subjects with psoriasis vulgaris in a chronic stable phase and mild to moderate plaque(s) covering a sufficient area to allocate 4 test fields on up to 3 comparable plaques. * Men and women aged 18-70 years (inclusive). * Sufficient target lesion(s) must be present on the trunk or extremities (excluding palms/soles); psoriatic lesions on the knees or elbows are not to be used as target lesions. * Plaques to be treated should have a comparable thickness of the EPB of the inflammatory infiltrate of at least 200 μm. * Plaques to be treated should have no more than a 2-fold difference in infiltrate thickness between the test fields. * Physical examination of skin must be without abnormal, clinical significant findings other than psoriasis vulgaris unless the investigator considers an abnormality to be irrelevant to the trial outcome. Key Exclusion Criteria: * Other skin disease noted on physical examination that is considered by the investigator to be relevant to the outcome of the trial. * Subjects with acute psoriasis guttata, psoriasis punctata, psoriasis erythrodermatica, pustular, exfoliative or inverse psoriasis. * History of psoriasis that was unresponsive or poorly responsive to topical treatments. * Topical antipsoriatics are not permitted on the same body area as plaques to be treated during the 4 weeks before first treatment and during the trial. * Systemic treatment with antipsoriatics e.g. corticosteroids, cytostatics, retinoids, dimethylfumarate, apremilast in the 3 months before first treatment and during the trial. * Systemic treatment with biological treatments: rituximab within 12 months, ustekinumab or secukinumab within 6 months before first treatment and during the trial. * Systemic treatment with biological treatments within 3 months before first treatment and during the trial. * Systemic treatment with any other biological treatments within the period of 5 half-lives of the biological before first treatment and during the trial. * UV-therapy or extensive exposure to UV radiation or sunlight within 4 weeks before first treatment and during the trial. * Treatment with concomitant medication that may affect and provoke or aggravate psoriasis, unless on a stable dose for 3 months before trial medication initiation. * Any other topical medication on the plaques to be treated during the trial. * Clinically significant abnormal vital signs (blood pressure, and pulse) at screening (V1). * History/symptoms of a clinically significant illness before first treatment (past 5 years) and during the trial that in the investigator's opinion may place the subject at risk. * History/symptoms of a clinically significant illness before first treatment (past 5 years) and during the trial that in the investigator's opinion may influence the trial outcome. * Other clinically significant abnormal laboratory results.