Antipruritic effect of DA-5018, a capsaicin derivative, in mice

The antipruritic effect of DA-5018, a capsaicin derivative, was examined in mice. Male ICR mice were topically pretreated with Zostrix-HP (0.075% capsaicin cream), 0.1%, 0.3% DA-5018 cream or cream base (control) twice daily for 4 days. One hour after the last application, itch was induced either by compound 48/80 (50 microg, s.c.) or leukotriene B4 (0.03 nmol, i.d.) injection into the rostral back of the animals, and the number of scratches made by the animals at the injection site was counted for 60 min post-injection. DA-5018 cream (both 0.1 and 0.3%) significantly inhibited compound 48/80-induced scratching when compared with the cream base control (p<0.01), while Zostrix-HP showed minimal inhibition of the scratching behavior. In leukotriene B4-induced itch model, Zostrix-HP and 0.3% DA-5018 cream significantly inhibited the scratching during the first 10-min period (p<0.01). The results suggest that DA-5018 cream can be used as an antipruritic agent and warrant clinical evaluation.