US Patent No. 9,687,433 B2
US Patent No. 9,687,433 B2; Ecstasy LLC, Chapel Hill, NC, has patented an anhydrous cosmetic or pharmaceutical dermatological formulation for use in depigmenting skin or otherwise lightening the tone of skin. The formulation is comprised an active depigmenting agent which is deoxyarbutin; a fatty phase in which the active depigmenting agent is not soluble; and an oily phase in which the active depigmenting agent is dissolved, said oily phase consisting of ethanol and/or isopropanol.
The formulation contains 0.1% or less water by weight relative to the total weight of the formulation. After storage of the sformulation at 40° C. for 60 days, it contains less than 20 ppm hydroquinone, either added or produced by degradation of deoxyarbutin to hydroquinone. The method of lightening the skin is comprised of topically applying a \therapeutically effective amount of the formulation according to claim 1.