The invention provides a salt of a tetrahydropyranylmethylaminopyrimidine amide, such as the citrate salt of (4-((3R,4R)-3-methoxytetrahydropyran-4-ylamino)piperidin-1-yl)(5-methyl-6-(((2R,6S)-6-(p-tolyl)tetrahydro-2H-pyran-2-yl)methylamino)pyrimidin-4-yl)methanone, pharmaceutical compositions containing the same, processes for preparing the same, and methods of medical treatment using the same.