Patent ID: 11926583
Assignee: EIRGEN PHARMA LTD.
Field: Pharmaceuticals (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 18:
19. A stabilized, crystalline 1,25-dihydroxyvitamin D2 composition, characterized by:
(a) being free of formate ester solvents;
(b) having no more than 0.5% total residual solvents as measured by a high performance liquid chromatography (“HPLC”) assay;
(c) comprising no more than 0.5% of 1β,25-dihydroxyvitamin D2, 5,6-trans 1,25-dihydroxyvitamin D2, 22-cis-1,25-dihydroxyvitamin D2, and 1,25-dihydroxyprevitamin D2 as measured by the HPLC assay;
(c) having an initial amount of 1,25-dihydroxyvitamin D2 as manufactured;
(f) having a second amount of the 1,25-dihydroxyvitamin D2 after the composition is stored at −20° C. under argon for a period of 12 months; and
(g) wherein the initial and second amounts each are in a range of 98.5-100% purity as measured by the HPLC assay, and the second amount is 99.5-100% of the initial amount.