Claims for Patent: 12,064,487

Summary for Patent: 12,064,487

Title:	Complex of gadolinium and a chelating ligand derived from a diastereoisomerically enriched PCTA and preparation and purification process
Abstract:	The present invention relates to a complex of formula (II) constituted of at least 90% of a diastereoisomeric excess comprising a mixture of isomers II-RRR and II-SSS of formulae: The present invention also relates to a process for preparing and purifying said complex of formula (II), and also to a composition comprising said complex.
Inventor(s):	Soizic le Greneur, Alain CHÉNEDÉ, Martine Cerf, Myriam Petta, Emmanuelle Marais, Bruno François, Caroline Robic, Stéphanie LOUGUET
Assignee:	Guerbet SA
Application Number:	US18/154,894
Patent Claims:	1. A method of medical imaging, the method comprising administering to a subject in need thereof a composition comprising: 1) a complex of formula (II) below: having a diastereoisomeric excess of at least 80% of a mixture of isomers II-RRR and II-SSS of formulae: and 2) a free macrocyclic ligand, wherein the composition has a concentration of free gadolinium of less than 1 ppm (m/v), and wherein the composition comprises from 0.002 to 0.4 mol/mol % of free macrocyclic ligand relative to the complex of formula (II). 2. The method of claim 1, wherein the composition comprises from 0.01 to 0.3 mol/mol % of free macrocyclic ligand relative to the complex of formula (II). 3. The method of claim 1, wherein the degree of purity of the complex of formula (II) is greater than 90% evaluated by chromatography. 4. The method of claim 1, wherein the degree of purity of the complex of formula (II) is greater than 95% evaluated by chromatography. 5. The method of claim 1, wherein the degree of purity of the complex of formula (II) is greater than 97% evaluated by chromatography. 6. The method of claim 1, wherein the isomers II-RRR and II-SSS are present in the mixture in a ratio of between 60/40 and 40/60. 7. The method of claim 1, wherein the composition has a concentration of complex of formula (II) of between 0.01 and 1.5 mol·L−1. 8. The method of claim 1, wherein the free macrocyclic ligand is selected from the group constituted of DOTA, NOTA, DO3A, BT-DO3A, HP-DO3A, PCTA, DOTA-GA and derivatives thereof. 9. The method of claim 1, wherein the pH of the composition is between 4.5 and 8.5. 10. The method of claim 1, wherein the composition further comprises a buffer selected from the group consisting of lactate, tartrate, malate, maleate, succinate, ascorbate, carbonate, Tris (Tris(hydroxymethyl)aminomethane), HEPES (2-[4-(2-hydroxyethyl)-1-piperazine]ethanesulfonic acid), MES (2-morpholinoethanesulfonic acid) buffers and mixtures thereof. 11. The method of claim 3, wherein the free macrocyclic ligand is DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid). 12. The method of claim 11, wherein the composition has a concentration of complex of formula (II) of between 0.3 and 0.6 mol·L−1. 13. The method of claim 11, wherein the composition further comprises a buffer being Tris (Tris(hydroxymethyl)aminomethane) and has a pH between 6.5 and 8.