Abstract: The invention relates to a novel choline cocrystal of 5-[(1Z,2E)-2-methyl-3-phenylpropenylidene]-4-oxo-2-thioxo-3-thiazolidineacetic acid. The preparation and characterization of the novel choline cocrystal according to various embodiments of the invention is described. The invention also relates to pharmaceutical compositions containing the novel choline cocrystal and the therapeutic use of the novel choline cocrystal to treat and/or prevent various conditions, including treating and/or preventing diabetic complications, treating and/or preventing homocystinuria reducing levels of homocysteine in blood serum, inhibiting aldose reductase, and affording cardioprotection in non-diabetic patients.