IP Library › Granted Patent US 12,570,663
Granted Patent B2
US 12,570,663 · App. 18/377,105 · Granted Mar 10, 2026

Crystal forms of an anti-sars CoV-2 agent

Inventors: Kaicheng Zhu (Belmont, MA); Tao Wang (Berkeley Heights, NJ); Joseph Helble (Hudson, MA); Anthony Toto (Boonton Township, NJ); Jiajun Zhang (Cambridge, MA); George G. Wu (Waltham, MA); Yat Sun Or (Waltham, MA)
Assignee: Enanta Pharmaceuticals, Inc.
C07D487/10A61K31/407C07B2200/13
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Quick Facts
Patent No.
US 12,570,663
App. No.
18/377,105
Granted
Mar 10, 2026
Kind
B2
Abstract

The present invention features crystalline forms of Compound I, including polymorphs and pseudopolymorphs, which are useful in the preparation of pharmaceutical compositions.

Claims (31)

1 . A crystalline Form 1 of Compound I,

wherein said crystalline form is characterized by an x-ray powder diffraction pattern having characteristic peaks at values of two theta (° 2θ) of 6.9, 8.3, 10.8, 11.9, 13.2, 13.7, 14.5, 15.4, 16.1, 18.2, 19.2, 20.0, 20.6, 21.7, 22.3, 23.9, 24.8, 25.2, 25.3, 26.1, 26.7, 27.6, 27.9, 28.9, 29.3, 30.1, 31.3, 31.3, 31.7, 32.5, 32.9, 34.7, 35.0, 35.8, 36.1, 36.8, 37.1, 37.8, 38.8, and 39.7.

2 . The crystalline form of claim 1 , further characterized by a differential Scanning Calorimeter thermogram having an Endotherm at 251° C. with an onset temperature at 250° C.

3 . The crystalline form of claim 1 , wherein said crystalline form is characterized by a differential Scanning Calorimeter thermogram having an Endotherm at 175° C. with an onset temperature at 175° C. and endotherm at 251° C. with an onset temperature at 250° C.

4 . A crystalline Form 2 of Compound I,

wherein said crystalline form is characterized by an x-ray powder diffraction (XRPD) pattern having characteristic peaks of two theta (° 2θ) of 6.9, 10.8, 11.9, 13.7, 14.5, 16.1, 18.1, 20.0, 20.6, 21.7, 22.3, 23.9, 24.8, 25.2, 26.1, 26.7, 27.9, 28.8, 29.2, 30.1, 31.3, 32.8, 34.3, 34.7, 35.77, 36.1, 37.1, and 39.9.

5 . The crystalline form of claim 4 , wherein said crystalline form is further characterized by a differential Scanning Calorimeter thermogram having an Endotherm at 175° C. with an onset temperature at 175° C. and endotherm at 251° C. with an onset temperature at 250° C.

6 . A crystalline Form 3 of Compound I,

wherein said crystalline form is characterized by an X-ray powder diffraction (XRPD) pattern having characteristic peaks at values of two theta (° 2θ) of 7.1, 8.7, 8.9, 11.0, 11.7, 13.1, 14.1, 15.2, 15.6, 16.2, 17.1, 17.5, 18.0, 19.2, 19.6, 20.4, 20.7, 21.9, 22.6, 23.5, 23.8, 24.7, 25.8, 26.3, 27.0, 28.1, 28.6, 29.7, 30.4, 31.3, 31.8, 32.3, 32.8, 33.3, 34.7, 35.6, 36.1, 36.5, 37.1, 37.9, and 38.2.

7 . A crystalline Form 4 of Compound I,

wherein said crystalline form is characterized by an X-ray powder diffraction (XRPD) pattern having characteristic peaks at values of two theta (° 2θ) of 4.4, 5.1, 7.1, 7.5, 8.5, 8.9, 9.8, 10.1, 10.3, 11.0, 11.7, 12.5, 13.1, 13.8, 14.1, 14.6, 14.8, 15.4, 15.8, 16.0, 16.9, 17.5, 17.9, 18.5, 19.2, 19.7, 20.1, 21.0, 21.8, 22.5, 23.4, 24.2, 24.9, 25.1, 26.2, 26.5, 27.8, 28.5, 29.4, and 31.0.

8 . A composition comprising a crystalline form according to claim 1 .

9 . A process for making a pharmaceutical composition comprising Compound I, comprising dissolving the crystalline form according to claim 1 in a solvent.

10 . A process for the preparation of the crystalline Form 1 of claim 1 ,

said process comprising the steps of:

1) preparing a solution of Compound I by dehydrating (3R,5'S)-1′-(N-methyl-N-(4,6,7-trifluoro-1H-indole-2-carbonyl)-L-leucyl)-2-oxospiro[indoline-3,3′-pyrrolidine]-5′-carboxamide (Compound n) in the presence of a suitable dehydration reagent or reagents, a suitable base, and a suitable solvent, thereby producing a solution of Compound 1;

2) concentrating the solution of Compound I from step 1 at a temperature from about 20° C. to about 80° C., to a solvent/Compound n ratio by volume (milliliter)/weight (gram) from about 2:1 to about 6:1;

3) optionally adding about 0.0001X (X=weight of Compound n in step 1) to about 0.1X of Form 1 of Compound I by weight to the concentrated solution from step 2, to induce crystallization of Form 1 of Compound I;

4) exchanging the solvent to a suitable solvent to a solvent/Compound n ratio by volume (milliliter)/weight (gram) from about 6:1 to about 10:1, at a temperature from about 20° C. to about 80° C., and the said suitable solvent is selected from anisole, toluene, xylene, ethyl acetate, isopropyl acetate, and mixtures of two or more thereof;

5) cooling the solution produced in step (4) to a temperature of about 0° C. to about 50° C., thereby producing Form 1 of Compound I; and

6) Filtering the product of step 5) to provide Form 1 of Compound I.

11 . The process as claimed in claim 9 , wherein the solvent is selected from anisole, toluene, xylene, ethyl acetate, isopropyl acetate, and mixtures of two or more thereof.

12 . A process for the preparation of the crystalline Form 1 of claim 1 ,

said process comprising the steps of:

I. adding Compound I to a first solvent thereby producing a solution; wherein the Compound I used to produce the solution is a solid form of Compound I or a mixture of two or more solid forms;

II. removing a portion of the first solvent from the solution, and then adding more of the first solvent;

III. repeating removing a portion of the first solvent from the solution and adding more of the first solvent until a solution of Compound I is produced with residual solvent controlled at no greater than a predetermined value;

IV. adding a second solvent to the solution to precipitate the Form 1 of Compound I; and

V. isolating the Form 1 of Compound I by filtration.

13 . The process as claimed in claim 12 , wherein the first solvent is EtOH, isopropanol, acetone, ethyl acetate, isopropyl acetate, or methyl tert-butyl ether.

14 . The method of claim 12 , wherein the second solvent water or n-heptane.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 8, 2024
From: ZHU, KAICHENG; WANG, TAO; HELBLE, JOSEPH; TOTO, ANTHONY; ZHANG, JIAJUN; WU, GEORGE G.; OR, YAT SUN
To: ENANTA PHARMACEUTICALS, INC.
Reel/Frame 066415/0860 →
Continuity (2)
Provisional Application 63413850 · Oct 6, 2022
Related Publication 20240132512A1 · Apr 25, 2024
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