Sodium thiosulfate-containing pharmaceutical compositions

A pharmaceutical composition comprising sodium thiosulfate pentahydrate and one or more pharmaceutically acceptable carriers or excipients, wherein the sodium thiosulfate pentahydrate contains no greater than 8 ppm of non-purgeable organic carbon, contains no greater than 0.05 ppm of mercury, contains no greater than 2 ppm of aluminum, contains no greater than 0.003% by weight of selenium, contains no less than 98% by weight and no greater than about 102% by weight of sodium thiosulfate on an anhydrous basis measured by ion chromatography, has a water content between 32% and 37% by weight, has a heavy metal content of no greater than 10 ppm, contains no greater than 200 ppm of chloride, contains no greater than 0.001% by weight of sulfide, contains no greater than 0.002% by weight of iron, contains no greater than 0.01% by weight of calcium, contains no greater than 0.005% by weight of potassium, contains no greater than 0.1% of sulfite, contains no greater than 0.5% of sulfate, contains no greater than 3 ppm of arsenic, contains no greater than 0.001% by weight of lead, has total aerobic count of microbial load of no greater than 100 CFU/g, has total yeast and mold count of no greater than 20 CFU/g, contains no greater than 0.02 EU/mg of bacterial endotoxins, contains no greater than 0.002% by weight of nitrogen compounds, contains no greater than 0.005% by weight of insoluble matter, contains no greater than 0.01% by weight of residual anti-caking agent, and contains no greater than ICH Q3C (R3) limits of organic volatile impurities, wherein a 10% aqueous solution of the solid sodium thiosulfate pentahydrate at 25° C. is colorless and has a pH between 6.0 and 8.0, and wherein the solid sodium thiosulfate pentahydrate is odorless crystals,

• wherein the pharmaceutical composition is an enteric-coated capsule or is formulated for rectal administration.