The epidermis of chronic idiopathic lichen planus during topical treatment with the vitamin D3 analogue KH 1060.

A parallel-group, double-blind, randomised study was performed to establish the effect of the vitamin D3 analogue KH 1060, in an ointment versus vehicle only, on the epidermal cell characteristics of chronic idiopathic lichen planus; KH 1060 also has marked immunosuppressive activity. A group of 10 patients were treated for 8 weeks with either KH 1060 ointment or vehicle only. In addition to the assessment of clinical scores, keratotome biopsies were taken before and after 8 weeks' treatment. Epidermal cell suspensions were prepared with trypsin and the suspensions incubated with TO-PRO-3 (DNA marker), RKSE 60 (marker for keratin 10-positive cells) and antivimentin (marker for all non-keratinocytes). In nine of the 10 patients, keratotome biopsies were obtained both before and after 8 weeks treatment. The vehicle alone had no significant effect on the clinical severity scores or epidermal cell characteristics. In contrast, the KH 1060 ointment resulted in a statistically significant reduction in the percentage of cells in S- and G2M phase and the percentage of vimentin-positive cells, but it did not affect the percentage of keratin 10-positive cells.