Safety and efficacy of combined use of 4-hydroxyanisole (mequinol) 2%/tretinoin 0.01% solution and sunscreen in solar lentigines.

The objective of this open-label, noncontrolled study was to evaluate the safety of a combination solution containing 4-hydroxyanisole (mequinol) 2%/tretinoin 0.01% (Solagé) with a sunscreen in the treatment of solar lentigines. The study included a total of 406 subjects for a treatment period up to 24 weeks. Efficacy was evaluated clinically by grading the pigmentation level of the treated areas on the face and forearms. A total of 378 subjects were included in the safety population. Of the 173 subjects with skin-related and treatment-related adverse events, severity was reported as mild in 79 subjects, moderate in 71, and severe in 23. Hypopigmentation was observed in 4 subjects and had definitively resolved in 3 of these subjects at the end of the study or after treatment had been discontinued. Halo hypopigmentation was reported in 16 subjects. No allergic reactions were observed. Efficacy evaluation was based on data for 370 subjects. A total of 325 (88%) subjects had facial target lesions almost clear to clear, and a total of 298 (81%) subjects had forearm target lesions almost clear to clear. Our study shows that the mequinol 2%/tretinoin 0.01% solution is effective, convenient, and safe in the treatment of solar lentigines.

Scalp psoriasis: synergy between the Malassezia yeasts and skin irritation due to calcipotriol.

To investigate if there is a synergy between the presence of the Malassezia yeasts and the adverse reaction during treatment of scalp psoriasis with calcipotriol scalp solution, patients were treated with itraconazole to reduce the number of Malassezia yeasts. This study was a double-blind, placebo-controlled parallel group study between oral itraconazole or placebo for 8 weeks in patients with scalp psoriasis. After 2 weeks, calcipotriol scalp solution was applied twice daily for 6 weeks. Altogether 137 patients, 67 in the itraconazole group and 70 in the placebo group, comprised the intention-to-treat population. There were 13 (19.4%) patients with local skin irritation in the itraconazole group compared to 33 (47.1%) in the placebo group (p < 0.001). The skin irritation was significantly lower in patients with a low number of cultured Malassezia yeasts (p = 0.017). Thus, when Malasessia was eliminated or the numbers reduced, the irritation produced by calcipotriol was significantly diminished.