Patent ID: 7902242

Claim:
A method of stabilizing 1-(2-methylpropyl)-1H imidazo[4,5-c]quinolin-4-amine (imiquimod) in a pharmaceutical cream formulated with the imiquimod and an oleic acid component during storage of the pharmaceutical cream prior to application of the pharmaceutical cream to a dermal or mucosal surface, said method comprising: formulating the pharmaceutical cream with a therapeutically effective amount of imiquimod and a pharmaceutically acceptable vehicle including an oleic acid component, wherein the oleic acid component contains at least about 80% oleic acid by weight as a fatty acid and has a peroxide value of no more than about 5 milliequivalents of oxygen per kilogram and contains less than about 1% by weight polar impurities at or prior to formulation of the pharmaceutical cream; storing the formulated pharmaceutical cream prior to use of the pharmaceutical cream; and maintaining a greater amount of the therapeutically effective amount of imiquimod in the pharmaceutical cream during said storing of the pharmaceutical cream, as compared to a reduced amount of imiquimod maintained in an identical pharmaceutical imiquimod cream but formulated with a compendial grade oleic acid component when the pharmaceutical cream and the identical pharmaceutical imiquimod cream are each stored under identical storage conditions for up to about six months after formulation.