Study to Investigate the Efficacy and the Safety of M518101 in Psoriasis Patients

Inclusion Criteria: * Who are able and willing to give signed informed consent * Who are male or females aged between 18 and 65 years with plaque psoriasis confirmed by the Investigator. * Who have less than 20% of body surface area (BSA) afflicted with plaques * Who are neither pregnant nor breast-feeding, nor plan to become pregnant during the study. Exclusion Criteria: * Who have a history of allergy to vitamin D3 derivative preparations. * Who have a history of relevant drug hypersensitivity. * Who have a history of contact dermatitis induced by a topical medicine. * Who are pregnant or lactating. * Who have any renal or hepatic insufficiency, or clinically significant cardiac, renal or hepatic disease. * Who have clinically relevant history or presence of any disease or surgical history other than psoriasis which is likely to affect the conduct of the study. * Whose serum calcium levels exceed the upper limit of reference range * Who have used any investigational medicinal product and/or participated in any clinical study within 24 weeks * Who have been treated with systemic therapy within 8 weeks * Who have been treated with biologics within 12 weeks * Who have been treated with topical therapy during the wash-out and lead-in period.