Patent attributes
Compositions comprising a calcium salt of L-leucovorin may be prepared that have a higher concentration of L-leucovorin than may be prepared using racemic leucovorin under similar conditions. Thus, some pharmaceutical compositions described herein may comprise a calcium salt of L-leucovorin at a relatively high concentration, such as at least about 15 mg/mL. Such a composition may be a stable aqueous solution, and may have near physiological pH, such as about 6 to about 8. Some pharmaceutical compositions may be substantially free of D-leucovorin, and may contain either: a) no EDTA, or b) less than about 1 mg/ml of EDTA. These compositions may be prepared, for example, by sonicating a mixture comprising the solid calcium salt of L-leucovorin and water. In some compositions, a calcium salt of L-leucovorin may be sufficiently soluble that it does not precipitate when it is injected.
