Sulfoalkyl ether cyclodextrin compositions

1. A composition comprising an excipient and a sulfoalkyl ether cyclodextrin (SAE-CD) composition, wherein the SAE-CD composition comprises a sulfoalkyl ether cyclodextrin and less than 100 ppm of a phosphate, wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to a drug-degrading agent, as determined by UV/vis spectrophotometry at a wavelength of 245 nm to 270 nm for an aqueous solution containing 300 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

2. The composition of claim 1 , wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to a color-forming agent, as determined by UV/vis spectrophotometry at a wavelength of 320 nm to 350 m for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

3. The composition of claim 1 , wherein the SAE-CD composition further comprises:

less than 20 ppm of a sulfoalkylating agent;

less than 0.5% wt. of an underivatized cyclodextrin;

less than 1% wt. of an alkali metal halide salt; and

less than 0.25% wt. of a hydrolyzed sulfoalkylating agent.

4. The composition of claim 1 , wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to a drug-degrading agent, as determined by UV/vis spectrophotometry at a wavelength of 245 nm to 270 m-n for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

5. The composition of claim 1 , wherein the sulfoalkyl ether cyclodextrin is a compound of Formula (I):

wherein p is 4, 5 or 6, and R 1 is independently selected at each occurrence from —OH or

—O—(C 2 -C 6 alkylene)-SO 3 − -T, wherein T is independently selected at each occurrence from pharmaceutically acceptable cations, provided that at least one R 1 is —OH and at least one R 1 is O—(C 2 -C 6 alkylene)-SO 3 − -T.

6. The composition of claim 5 , wherein R 1 is independently selected at each occurrence from —OH or —O—(C 4 alkylene)-SO 3 − -T, and -T is Na + at each occurrence.

7. The composition of claim 1 , wherein the SAE-CD composition comprises:

less than 50 ppm of a phosphate;

less than 10 ppm of a sulfoalkylating agent;

less than 0.2% wt. of an underivatized cyclodextrin;

less than 0.5% wt. of an alkali metal halide salt; and

less than 0.1% wt. of a hydrolyzed sulfoalkylating agent;

and

wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to the color-forming agent, as determined by U/vis spectrophotometry at a wavelength of 320 nm to 350 nm for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

8. The composition of claim 1 , wherein the SAE-CD composition comprises:

less than 10 ppm of a phosphate;

less than 2 ppm of a sulfoalkylating agent;

less than 0.1% wt. of an underivatized cyclodextrin;

less than 0.2% wt. of an alkali metal halide salt; and

less than 0.08% wt. of a hydrolyzed sulfoalkylating agent; and

wherein the SAE-CD composition has an absorption of less than 0.1 A.U. due to the color-forming agent, as determined by UV/vis spectrophotometry at a wavelength of 320 nm to 350 nm for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

9. The composition of claim 8 , wherein the SAE-CD composition comprises:

less than 5 ppm of a phosphate;

less than 0.1% wt. of an alkali metal halide salt; and

less than 0.05% wt. of a hydrolyzed sulfoalkylating agent.

10. A composition comprising an excipient and a sulfoalkyl ether cyclodextrin (SAE-CD) composition, wherein the SAE-CD composition comprises a sulfobutyl ether cyclodextrin having an average degree of substitution of 7 and less than 100 ppm of a phosphate, wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to a drug-degrading agent, as determined by UV/vis spectrophotometry at a wavelength of 245 run to 270 nm for an aqueous solution containing 300 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

11. A process for preparing a composition comprising an excipient and a sulfoalkyl ether cyclodextrin (SAE-CD) composition, wherein the SAE-CD composition comprises a sulfoalkyl ether cyclodextrin, the process comprising:

(a) mixing in an aqueous medium a cyclodextrin with a sulfoalkylating agent in the presence of an alkalizing agent to form an aqueous reaction milieu comprising a sulfoalkyl ether cyclodextrin, one or more unwanted components, and one or more drug-degrading impurities;

(b) conducting one or more separations to remove the one or more unwanted components from the aqueous milieu to form a partially purified aqueous solution comprising the sulfoalkyl ether cyclodextrin and the one or more drug-degrading impurities, wherein the one or more separations include a process selected from: ultrafiltration, diafiltration, centrifugation, extraction, solvent precipitation, and dialysis;

(c) treating the partially purified aqueous solution with a phosphate-free activated carbon two or more times to provide the SAE-CD composition comprising the sulfoalkyl ether cyclodextrin and less than 100 ppm of a phosphate, wherein the SAE-CD composition has an absorption of less than 0.5 A.U. due to a drug-degrading agent, as determined by UV/vis spectrophotometry at a wavelength of 245 nm to 270 nm for an aqueous solution containing 300 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length; and

(d) combining the SAE-CD composition with an excipient.

12. The process of claim 11 , wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to a color-forming agent, as determined by UV/vis spectrophotometry at a wavelength of 320 nm to 500 nm for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

13. The process of claim 11 , wherein the SAE-CD composition comprises:

less than 50 ppm of a phosphate;

less than 10 ppm of a sulfoalkylating agent;

less than 0.2% wt. of an underivatized cyclodextrin;

less than 0.5% wt. of an alkali metal halide salt; and

less than 0.1% wt. of a hydrolyzed sulfoalkylating agent;

wherein the SAE-CD composition has an absorption of less than 0.5 A.U. due to the drug-degrading agent, as determined by UV/vis spectrophotometry at a wavelength of 245 nm to 270 nm for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length; and

wherein the SAE-CD composition has an absorption of less than 0.2 A.U. due to the color-forming agent, as determined by UV/vis spectrophotometry at a wavelength of 320 nm to 350 nm for an aqueous solution containing 500 mg of the SAE-CD composition per mL of solution in a cell having a 1 cm path length.

14. The process of claim 11 , wherein the sulfoalkyl ether cyclodextrin is a compound of Formula (1):

wherein p is 4, 5 or 6, and R 1 is independently selected at each occurrence from —OH or

—O—(C 2 -C 6 alkylene)-SO 3 − -T, wherein T is independently selected at each occurrence from pharmaceutically acceptable cations, provided that at least one R 1 is —OH and at least one R 1 is O—(C 2 -C 6 alkylene)-SO 3 -T.

15. The process of claim 14 , wherein R 1 is independently selected at each occurrence from —OH or —O—(C 4 alkylene)-SO 3 − -T, and -T is Na + at each occurrence.

16. The process of claim 11 , wherein the treating comprises:

adding a phosphate-free particulate or powdered activated carbon to the partially purified aqueous solution while mixing, separating the activated carbon from the solution, and repeating the adding and the separating at least once until the amount of drug-degrading agent in the solution is reduced to a target level; or

passing and recycling the partially purified aqueous solution through a mass of phosphate-free activated carbon in a flow-through apparatus until the amount of drug-degrading agent in the solution is reduced to a target level.

17. The process of claim 16 , wherein the conducting comprises passing and recycling two or more times, wherein each passing is with a different mass of activated carbon.

18. The process of claim 17 , wherein the activated carbon present during the conducting is about 12% by weight of the sulfoalkyl ether cyclodextrin, and the conducting is performed for at least about 2 hours.

19. A product prepared by the process of claim 11 .