Treatment of hyperpigmented spots on human skin

INTERVENTION: Participants qualify for study participation by having at least two solar lentigines appropriate for the intended measurements, i.e., suitable in size and coloration. During a two‐day preconditioning period, prior to the baseline visit, participants are not allowed to use any moisturizing skin care products on the test sites. At the baseline visit, the color of the spots and the surrounding skin is measured by spectrophotometry. Treatment locations are based upon the positions of the available spots, location of the measured spots is documented by clinical photography. After baseline measurements, the investigator demonstrates correct application of the products with a spot applicator, and trains the participants in self‐application. Only the selected spots should to be covered with the product without treatment of the surrounding skin. Each subject treats two spots, one lentiginous spot is treated with a product containing the active ingredient, one spot is treated with vehicle. Treatment is assigned to the individual spots according to a randomization scheme (using Siemens PLM Software Teamcenter 11.2.3.1). For a twelve week treatment period, the participants apply the test products twice daily to the spots on the forearm skin, avoiding the surrounding skin. CONDITION: Volar forearms with solar Lentigines, but otherwise healthy skin ; Skin and Connective Tissue Diseases ; Volar forearms with solar Lentigines, but otherwise healthy skin PRIMARY OUTCOME: Skin colour contrast of lentigines to surrounding skin is measured using a spectrophotometer at baseline, 4,8, and 12 weeks. SECONDARY OUTCOME: 1. The size and colour of the lentiginous spots is measured using photographs at baseline, 4, 8, and 12 weeks; 2. The forearm skin is measured using visual inspections at baseline, 4, 8, 12 weeks for signs of irritation INCLUSION CRITERIA: 1. Females/ males between 50 and 70 years of age in generally good health 2. Solar Lentigines on the arms but otherwise healthy, undamaged skin in the test sites 3. Fitzpatrick skin phototype I, II, III or IV 4. Ability to understand the study concept (intellectual capacity and language skills) and to comply with the test schedule and study rules 5. Participant is willing and able to give written informed consent