Prodrugs of 2,4-pyrimidinediamine compounds and their uses

A method of treating an autoimmune disease in a mammal afflicted with the disease, the method comprising administering to the mammal an effective amount of an oral dosage formulation comprising a hydrate of the prodrug salt:

• and a pharmaceutically-acceptable carrier, excipient, and/or diluent;
• wherein:
• M is Na;
• the prodrug salt hydrate present in the oral dosage formulation comprises crystalline prodrug salt hydrate;
• and
• the powder X-ray diffraction data of the crystalline prodrug salt hydrate comprises a characteristic peak at a two theta value of 17.2 ±0.1° in response to radiation of wavelength 1.54059±Å, wherein the autoimmune disease is associated with nonanaphylactic hypersensitivity reactions (Type II, Type III and/or Type IV hypersensitivity reactions) or mediated, at least in part, by activation of the FcyR signaling cascade in monocyte cells.