Human dermal safety studies with eflornithine HCl 13.9% cream (Vaniqa (TM)), a novel treatment for excessive facial hair

Eflornithine HCl 13.9% cream (Vaniqa(TM)) is a novel treatmelztfor the mana gement of unwanted facial hair in women. This paper reports the results of four modified open-label, within-subject vehicle-controlled studies evaluat ing the dermal safety of this topical treatment. In a repeated insult patch test (230 subjects), erythema with oedema occurred in 38.9% of subjects tr eated with eflornithine HCl 13.9% cream and 4.8% of subjects treated with v ehicle cream. Challenge applications at previously untested sites following the three-week induction period produced noticeable erythema or greater on only four sites treated with eflornithine HCl 13.9 % cream and one vehicle -treated site. The erythema at these sites subsided substantially within 24 hours. Ivr a three-week cumulative irritation study (230 subjects), the me an irritation score for sites treated with eflornithine HCl 13.9% cream was 1.33, compared with 0.76 at vehicle-treated sires and 3.09 at positive-con trol (sodium lauryl sulphate-treated) sites (p < 0.001 between all three gr oups). In a phototoxicity study (25 subjects), irradiated sites showed eith er no reaction (40% of both sites treated with eflornithine HCl 13.9% cream and vehicle-treated sites), or mild erythema subsiding in all cases but on e within 24 hours. No reaction was seen at non-irradiated sites. In a photo contact allergy study (30 subjects), challenge with eflornithine HCl 13.9% cream or its vehicle alone produced either Mo reaction or mild erythema sub siding within 24 hours at both irradiated and nonirradiated sites. No serio us adverse events were reported during the studies, and the only adverse ev ents considered related to treatment were pruritus (three subjects) and dry skin at test site tone subject. These results demonstrate that eflornithin e HCl 13.9 % cream does not have contact sensitising, photocontact allergic or phototoxic properties. It can cause irritation under exaggerated condit ions of use. Eflornithine HCl 13.9% cream, therefore, has a favourable derm al safety profile appropriate for a topical treatment to be applied routine ly.