USOO5811547A United States Patent (19) 11 Patent Number: 5,811,547 Nakamichi et al. (45) Date of Patent: Sep. 22, 1998 54 METHOD FOR INDUCING CRYSTALLINE 56) References Cited STATE TRANSTION IN MEDICINAL SUBSTANCE U.S. PATENT DOCUMENTS 4,129,649 12/1978 Inoue et al. ............................. 424/182 75 Inventors: Kouichi Nakamichi, Shiga; Shougo 5,160,680 11/1992 Serpelloni et al. ..................... 264/126 Izumi, Kyoto; Masaaki Oka, Osaka, 5,256.234 10/1993 Mutaguchi et al. ... ... 156/224.27 all of Japan 5,385,749 1/1995 Serpelloni et al. ..................... 426/658 73 Assignee: Nippon Shinyaju Co., Ltd., Kyoto, FOREIGN PATENT DOCUMENTS Japan O 177 428 10/1985 European Pat. Off.. O 490 768 A1 12/1991 European Pat. Off.. 21 Appl. No.: 416,815 O 580 860A1 4/1992 European Pat. Off.. 22 PCT Filed: Oct. 13, 1993 60-190723 9/1985 Japan . 86 PCT No.: PCT/JP93/01469 OTHER PUBLICATIONS Obandie et al., J. of Applied Polymer Science, vol. 37, pp. S371 Date: Jun. 9, 1995 1713–1726 (1989). S 102(e) Date: Jun. 9, 1995 Journal of Pharamaceutical Sciences, vol. 62, No. 1, Jan. 1973 F.W. Goodhart, et al. “Design and Use of A Laboratory 87 PCT Pub. No.: WO94/08561 Extruder for Pharmaceutical Granulations”, pp. 133-136. PCT Pub. Date: Apr. 28, 1994 Primary Examiner Mukund J. Shah Assistant Examiner K. Wong Related U.S. Application Data Attorney, Agent, or Firm-Graham & James LLP 63 Continuation-in-part of Ser. No. 129,133, Nov. 15, 1993, 57 ABSTRACT Pat. No. 5,456,923. This invention has for its object to provide a method of 30 Foreign Application Priority Data inducing a transition in crystalline State of a crystallizable Japan .................................... 4-3O3O85 medicinal Substance with great ease and improved efficiency Oct. 14, 1992 JP and uniformity on a high production Scale. According to the 51) Int. Cl. ....................... C07D 209/32; CO7D 223/24 invention, an extruder is used for inducing a transition from 52 U.S. Cl. ............................ 540/589: 548/500; 564/45; one crystalline State (A) to another crystalline State in a 564/213 crystallizable medicinal Substance. 58 Field of Search ............................... 548/500; 564/45, 564/213; 540/589 12 Claims, 5 Drawing Sheets U.S. Patent Sep. 22, 1998 Sheet 1 of 5 5,811,547 inlet side Outlet side A inlet side A A 4. outlet side U.S. Patent Sep. 22, 1998 Sheet 2 of 5 5,811,547 5k A. U > m () 49 H O 49 U H t sA -Wul 4. 20 40 60 Diffraction Angle (26) Eig - 3 8k A. U > 4. () H O s 49 t ar A 4. 20 40 60 Diffraction Angle (26) Fig - 4 U.S. Patent Sep. 22, 1998 Sheet 3 of 5 5,811,547 4k A. U > ar O) H O ar RS H ar A 4. 20 40 60 Diffraction Angle (20) Eig - 5 6K A. U > m O) 4. H O ar U t Wy ar are usaved are 4. 2O 40 60 Diffraction Angle (26) Fig - 6 U.S. Patent Sep. 22, 1998 Sheet 4 of 5 5,811,547 2 Ok 4. "to - 60 Diffraction Angle (26) Efig - 7 4. k i 4. 20 40 60 Diffraction Angle (26) Erig - 8 U.S. Patent Sep. 22, 1998 Sheet 5 of 5 5,811,547 3 Ok. O > g O) H O ar r A Diffraction Angle (20) Eig - 9 5 Ok A. U > ar H O ar A 4. 2O 40 60 Diffraction Angle (26) Big - - O 5,811,547 1 2 METHOD FOR INDUCING CRYSTALLINE invention has for its object to provide a method of inducing, STATE TRANSTION IN MEDICINAL expediently, efficiently, uniformly, continuously and on a SUBSTANCE high production Scale, a transition of crystalline State, for example: This is a continuation in part application of U.S. Ser. No. 5 (1) from a crystallizable active Substance in metastable 08/129,133, filed Nov. 15, 1993, now U.S. Pat. No. 5,456, crystalline State or in amorphous Solid State to stable 923, issued Oct. 10, 1995, and is a 371 national filing of crystals, PCT/JP93/01469, filed Oct. 13, 1993. (2) a crystallizable active Substance in stable crystalline State or in amorphous Solid State to metastable crystals, TECHNICAL FIELD (3) a crystallizable active Substance in stable crystalline This invention relates to a method of inducing a transition State or in metastable crystalline State to an amorphous Solid, of crystalline State in a crystallizable medicinal Substance. O AS used in this specification, the term stable crystal (4) a crystallizable active Substance in heterogenous crys means any crystal that is in thermodynamically stable crys 15 talline State to homogeneous crystals. talline State and the term metastable crystal means any The inventors of this invention found that the above crystal that is in thermodynamically unstable crystalline mentioned object can be accomplished by utilizing an State. The term 'crystalline State is used referring to any of extruder which enables a continuous processing of the load Stable crystal, metastable crystal and amorphous and have arrived at the present invention. (noncrystalline) Solid. The term heterogenous crystal In the pharmaceutical field, few technologies utilizing an means a crystal not in a singular crystalline State. extruder are known. The term 'extruder means any Screw extruder that is in At this junction, the mechanism of the main part (work broad use chiefly in food industry for the processing of food processing part) of the extruder is briefly described. Gener materials (cereals, proteins, animal meat, fish meat, etc.). ally the main part of an extruder comprises, as illustrated in 25 FIG. 1, a cylindrical structure called “barrel, a die which BACKGROUND ART corresponds to a delivery port, and a Screw. The barrel The conventional technology for inducing a transition of usually comprises a plurality of unit barrels and the Screw crystalline State in a medicinal Substance includes extends through them. The Screw is available in various recrystallization, heating, freeze-drying, pulverizing and So types, namely trapezoidal Screw, trapezoidal cut Screw, O. trapezoidal reverse cut Screw, ball Screw, kneading paddle: However, none of these conventional methods are capable etc., which can be used in a desired combination. The load of inducing a transition of crystalline State expediently, fed to the extruder is forced by the screw to advance, shorn efficiently, uniformly and on a mass Scale and, therefore, are and blended by the screw within the barrel structure and extruded from the orifice or orifices of the die. Usually, the not well Suited for commercial application. One of the 35 reasons for their incapability is that because these technolo temperature of each unit barrel and that of the die can be gies are invariably batch processes, large-scale equipment is independently controlled. required for mass processing but the larger the equipment, The extruder is available in two general types, namely a the greater is the temperature gradient created in the pro Single-Screw extruder comprising one Screw and a multi cessing load, So that homogeneous crystals cannot be easily Screw extruder comprising two or more Screws. While this obtained. Taking the recrystallization process as an example, 40 invention can be carried into practice using either type of judicious Selection of the recrystallization Solvent, detailed extruder, the use of a multi-Screw extruder, particularly a analysis of recrystallizing temperature and other parameters, twin-Screw extruder, is preferred. Compared with a single and accurate control of recrystallization conditions are Screw version, a twin-Screw extruder is more efficient in that essential. In the case of freeze-drying, the protracted pro the plural Screws interferring with each other precludes cessing time is also a detracting factor. 45 follow-up movement of the active Substance and, moreover, the intermeshing of the Screws provides a high energy output The present invention will be clearly seen from the physically, thus assisting in the induction of a transition of following discussion and the drawings in which: crystalline State. BRIEF DESCRIPTION OF THE DRAWINGS In the practice of this invention, Such an extruder as is in 50 routine use by food industry can be utilized as it is. FIG. 1 is a Schematic cross-section view of the main part The mode of use of the extruder in the practice of this of the extruder used to effect the method of the present invention is now described, referring to Specific embodi invention; mentS. FIG. 2, is a Schematic representation of change in crys 55 For example, in this invention, the main part of the talline State of the medical Substance being processed in the extruder can be utilized as divided into two Zones, namely extruder of FIG. 1; a melting Zone and a cooling Zone as illustrated in FIG. 2. FIGS. 3-10 are powder diffraction patterns, with each The melting Zone is the Zone in which the medicinal figure showing comparative diffraction patterns for various Substance is melted and the cooling Zone is the Zone in Substances prior to and after processing in accordance with 60 which the medicinal Substance melted in Said melting Zone the present invention. is solidified. In the practice of this invention, the melting Zone can be DISCLOSURE OF INVENTION defined by one or more barrels. If and when the medicinal The object of this invention is to provide a method of material can be Successfully melted, even a single barrel can inducing a transition of crystalline State in a crystallizable 65 Serve as the melting Zone. However, the proper number of medicinal Substance which overcomes the disadvantages of barrels defining the melting Zone is dependent on the melt the above-mentioned prior art methods.