Crystal forms of (3R)-1-(2-methylalanyl-D-tryptophyl)-3-(phenylmethyl)-3-piperidinecarboxylic acid 1,2,2-trimethylhydrazide
Crystalline polymorphs of (3R)-1-(2-methylalanyl-D-tryptophyl)-3-(phenylmethyl)-3-piperidinecarboxylic acid 1,2,2-trimethylhydrazide which are useful as pharmaceutical agents are disclosed. Methods of production and isolation of these polymorphs and pharmaceutical compositions which include these polymorphs and pharmaceutical methods of treatment are also disclosed. The crystalline polymorphs of the present invention are useful as they act directly on the pituitary gland cells to release growth hormone.
1. Crystalline (3R)-1-(2-methylalanyl-D-tryptophyl)-3-(phenylmethyl)-3-piperidinecarboxylic acid 1,2,2-trimethylhydrazide (anamorelin) monohydrate having an X-ray powder diffraction pattern having at least four 2θ values measured using Cu Kα radiation selected from the group consisting of 10.1, 11.1, 17.6, 20.0, and 20.8.
2. The crystalline anamorelin monohydrate of claim 1 , comprising methanol as an organic volatile impurity.
3. A process for preparing the crystalline anamorelin monohydrate of claim 1 comprising: a) producing a mixture of anamorelin and a solvent comprised of methanol and water; b) precipitating crystalline anamorelin from the solvent; and c) isolating the crystalline anamorelin.
4. The process of claim 3 , wherein the solvent is a mixture of water and methanol and the volume percentage of methanol in the mixture is from about 5% to about 95%.
5. The process of claim 3 , wherein the solvent is a mixture of water and methanol and the volume percentage of methanol in the mixture is from about 20% to about 80%.
6. The process of claim 3 , wherein the solvent is a mixture of water and methanol and the volume percentage of methanol in the mixture is from about 40% to about 60%.
7. The process of claim 3 , wherein the solvent is at an elevated temperature while combining with the anamorelin in step a), or the solvent is heated to an elevated temperature after combining with the anamorelin in step a).
8. The process of claim 7 , wherein said elevated temperature is from about 40° C. to about 100° C.
9. The process of claim 7 , wherein said elevated temperature is from about 50° C. to about 80° C.
10. The process of claim 7 , wherein said elevated temperature is from about 65° C. to about 75° C.
11. The process of claim 3 , wherein the crystals are precipitated in step b) by cooling the solvent.
12. A process for preparing the crystalline anamorelin monohydrate of claim 1 comprising: a) combining {1-[(1R)-2-](3R)-3-Benzyl-3-(N,N,N′-trimethylhydrazinocarbonyl)piperidin-1-yl-]-1-(1H-indol-3-ylmethyl)-2-oxo-ethylcarbamoyl]-1-methylethyl}carbamic acid tert-butyl ester (protected anamorelin) with a solvent; b) combining the mixture from step a) with an acid; c) neutralizing the mixture formed in step b); d) precipitating crystals of anamorelin from the solvent; and e) isolating the crystals.
13. The process of claim 12 , wherein the solvent in step a) is methanol, and the mixture is neutralized in step c) with a mixture of potassium hydroxide and water.
14. The process of claim 12 , wherein the acid is methanesulfonic acid.
15. The process of claim 12 , wherein the solvent is at an elevated temperature while combining with said protected anamorelin in step a), or the solvent is heated to an elevated temperature after combining with said protected anamorelin in step a).
16. The process of claim 15 , wherein the elevated temperature is from about 50° C. to about 75° C.
17. The process of claim 12 , wherein the crystals are precipitated in step d) by cooling the solvent.