Ursodesoxycholic acid oral suspension and preparation thereof

Abstract

The invention discloses a preparation method of an ursodesoxycholic acid oral suspension, which is characterized in that an amorphous ursodesoxycholic acid raw material is prepared by a hot melt extrusion method, the apparent solubility of an indissolvable drug ursodesoxycholic acid is improved, and the dissolution rate of the prepared suspension preparation is further increased, so that the purpose of improving the in-vivo bioavailability of the preparation is achieved. Besides, the variety and dosage of the suspending aid in the prescription are optimized, the defects that the existing ursodesoxycholic acid oral suspension is high in viscosity and high in filling equipment requirement are overcome, the method is simple in process and convenient to operate, and the prepared ursodesoxycholic acid oral suspension has the advantages of being low in viscosity, good in stability and easy to industrially produce.

Description

Technical Field

[0001] The invention relates to the technical field of pharmaceutical preparations, and in particular to a method for preparing an ursodeoxycholic acid oral suspension. Background Art

[0002] Ursodeoxycholic acid (UDCA), chemically known as 3α,7β-dihydroxy-5β-cholestane-24 acid, is an endogenous bile acid in the human body. Ursodeoxycholic acid can not only promote the dissolution of cholesterol stones, but also replace the hydrophobic bile acids in the human bile acid pool that have cell-damaging effects, thereby playing a pharmacological role in protecting bile duct epithelial cells, inhibiting hepatocyte apoptosis, regulating stem cell immunity, stimulating bile secretion, etc. At present, the main indications of ursodeoxycholic acid approved worldwide are cholesterol gallstones, cholestatic liver disease and bile reflux gastritis, especially the treatment of primary biliary cholangitis (PBC). It is the only drug of choice approved by the FDA for various cholestatic liver diseases such as primary cholestatic cirrhosis and primary sclerosing cholangitis.

[0003] Ursodeoxycholic acid is a weakly acidic compound. According to the Japanese Medical Drug Quality Information Collection, the solubility of ursodeoxycholic acid in water is only 0.0064 mg / ml, and the solubility in pH 1.2 and pH 6.8 media is 0.0027 mg / ml and 0.222 mg / ml respectively. Ursodeoxycholic acid is basically insoluble in the acidic environment of the stomach, but can be dissolved in the environment of pH 6.8 and above in the small intestine. The dissolved ursodeoxycholic acid can be rapidly absorbed in the proximal small intestine. Therefore, the apparent solubility of the raw material is a key factor affecting its absorption in the proximal small intestine, which in turn affects the bioavailability of ursodeoxycholic acid preparations in the body.

[0004] The original developer of ursodeoxycholic acid oral preparations is Dr. Falk Pharmaceuticals of Germany. The preparation types include tablets, capsules and suspensions. As early as 2000, tablets and capsules were approved for marketing in China. In recent years, oral suspensions, as a new type of liquid preparation, have become increasingly popular with patients due to their fast absorption rate, ease of administration for the elderly and children, and ability to achieve precise dosing based on weight. As a drug classified as BCSII in biopharmaceutics, the dissolution rate of ursodeoxycholic acid is the rate-limiting step in the absorption process of the drug in vivo. Therefore, how to improve the solubility of poorly soluble drugs is the key and technical difficulty to improve the bioavailability of such drugs. The final dissolution rate of the original preparation of ursodeoxycholic acid oral suspension currently available in the market with a specification of 0.25g / 5ml in a pH 6.8 medium is less than 60%. It has been reported in the literature (Parquet M, Bioavailability, gastrointestinal transit, solubilization and faecal excretion of ursodeoxycholic acid in man [J]. Eur J Clin Invest, 1985, 15: 171-178) that oral preparations of ursodeoxycholic acid with a strength of more than 250 mg are difficult to dissolve completely in the small intestine at pH 6.8 and cannot be completely absorbed in the body. Therefore, how to improve the solubility of poorly soluble drugs is the key and technical difficulty to improve the bioavailability of ursodeoxycholic acid drugs.

[0005] The existing pharmaceutical technology for improving the bioavailability of ursodeoxycholic acid oral suspension is mainly to prepare nanosuspensions. For example, patents CN101606906A and CN113975233A both disclose methods for preparing nano ursodeoxycholic acid oral suspensions. However, the preparation of nanosuspensions has the disadvantages of high cost, complex process, poor stability, and the need to add additional stabilizers.

[0006] Therefore, designing a formulation and preparation process that can improve the bioavailability of ursodeoxycholic acid oral suspension and enable simple and stable industrial production is a primary technical problem that urgently needs to be solved in this field.

[0007] In addition, the ursodeoxycholic acid oral suspension currently produced by the original German Dr. Falk Pharmaceutical Factory has high viscosity and high requirements for filling equipment. Therefore, improving the fluidity of ursodeoxycholic acid oral suspension to make it suitable for conventional production equipment is also a technical problem that needs to be solved. Summary of the invention

[0008] In order to overcome the limitations and defects of the prior art, the inventors conducted a large number of experimental studies, starting from improving the apparent solubility of ursodeoxycholic acid API in pH 6.8 phosphate medium, and tried a variety of methods to increase the solubility of poorly soluble drugs. It was unexpectedly found that the in vitro dissolution rate of ursodeoxycholic acid in amorphous state was about 40% higher than that of crystalline ursodeoxycholic acid. Even more surprising is that the differential scanning calorimetry (DSC) results of the amorphous ursodeoxycholic acid API prepared by the present invention showed that its glass transition temperature was as high as 107.7°C, indicating that ursodeoxycholic acid in amorphous state theoretically has good physical stability, and the results of the subsequent 6-month accelerated stability study also confirmed this.

[0009] The inventors tried a variety of methods for preparing amorphous drugs, including solvent precipitation, solvent rotary evaporation, melt quenching, and physical grinding. Finally, based on the experimental results of the melt quenching method, they developed a hot melt extrusion method that can continuously and stably prepare high-purity amorphous ursodeoxycholic acid raw materials. This preparation method uses a segmented twin-screw hot melt extrusion equipment, and the key process parameters are the barrel temperature setting, screw speed and cooling rate.

[0010] After many attempts, it was determined that the temperature setting range of the hot melt extruder barrel is 180℃~210℃, of which the temperature of segment 1 (near the feed port area) is 180℃~190℃. Above this temperature range, the API will stick prematurely, resulting in poor feeding, while below this temperature, ursodeoxycholic acid will not be able to melt, resulting in extrusion failure. In addition, to ensure that the API does not overheat, discolor and degrade, the extrusion temperature must be controlled below 210℃. Within this temperature range, the viscosity of the ursodeoxycholic acid fluid is relatively high. To avoid excessive torque, the equipment screw speed cannot be too fast. It has been confirmed that the speed range is more suitable to be controlled at 50~100 revolutions.

[0011] On the other hand, the inventors also conducted a comparative study on the cooling methods of the extrudate. During the experiment, it was found that the cooling rate of the ursodeoxycholic acid API after melting is crucial to the preparation of high-purity ursodeoxycholic acid amorphous material. The faster the cooling rate, the higher the crystal purity of the prepared ursodeoxycholic acid amorphous material. We tried various cooling methods, including natural air cooling by conveyor belt, water bath cooling, and rapid cooling by cooling rollers. The final test results showed that a small amount of crystalline ursodeoxycholic acid existed in the ursodeoxycholic acid amorphous powder obtained by natural air cooling and circulating water bath cooling. Only by using cooling rollers for cooling operations can high-purity amorphous ursodeoxycholic acid be successfully prepared. The cooling roller technology can spread and roll out the hot melt on the cooling roller, and can achieve a cooling temperature difference of more than 100°C in a short time, thereby meeting our needs for rapid cooling of the dissolution.

[0012] The present invention also provides a method for preparing an ursodeoxycholic acid oral suspension having good stability and high bioavailability, comprising the following steps: 1) API pretreatment: The crystalline ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve, and then hot-melt extruded, cooled, and crushed to obtain glassy flakes, which are then air-flow-pulverized to obtain amorphous ursodeoxycholic acid API with a particle size D90 ranging from 5 to 30 μm; 2) Weigh an appropriate amount of the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose complex, place it in deionized water and homogenize it at high speed for 5-15 minutes at a shear rate of 10-20 kr / min, and stir for 1-2 hours to obtain a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion; 3) Add the prescribed amount of antibacterial agent, pH adjuster, antiflocculant and flavoring agent to the aqueous dispersion, stir evenly, then add the prescribed amount of treated raw materials and stir evenly at a low speed; 4) Set the shear speed to 5~10kr / min and homogenize at high speed for 30~60min to obtain the particle size D 90 Ursodeoxycholic acid oral suspension in the range of 1-10 μm.

[0013] In the method for preparing the ursodeoxycholic acid oral suspension of the present invention, the initial particle size D of the amorphous ursodeoxycholic acid raw material is 90 The range is 5~30μm, preferably 10~20μm. When the particle size is less than 5μm, after homogenization, some raw material particles will be less than 1μm. Due to the large specific surface area, the system stability is poor, and the suspension is prone to flocculation. When the particle size is greater than 30μm, the dissolution rate of the raw material will slow down, thereby affecting the absorption in the body. The test results show that when the particle size D in ursodeoxycholic acid oral suspension is 90 When the range is 1~10μm, the product has good stability and fast dissolution rate, and the final dissolution rate is close to 80%, while the dissolution rate of the original formulation on the market under the same conditions is less than 60%.

[0014] The suspending agent used in the ursodeoxycholic acid oral suspension of the present invention is a microcrystalline cellulose-sodium carboxymethyl cellulose complex. The suspension using microcrystalline cellulose-sodium carboxymethyl cellulose as a suspending agent is thixotropic. When the network structure formed by the microcrystalline cellulose sodium particles in water is subjected to a shear force above the yield value, the network structure is destroyed, and the apparent viscosity decreases rapidly. Therefore, compared with the suspension formed by other suspending agents, this product has no sticky feeling when taken, and the mouthfeel is more lubricated and comfortable. After the inventor screened the various suspending agent models including CL-611, RC-591 and RC-581, the microcrystalline cellulose-sodium carboxymethyl cellulose model CL-611 was finally selected to prepare the oral suspension. The flowability of the prepared suspension product is better than that of the original preparation, and certain technical advantages are possessed in production amplification convenience and quantitative accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the present invention, the drawings required for describing the embodiments are introduced below.

[0016] Figure 1 PXRD diffraction patterns of crystalline and amorphous ursodeoxycholic acid API.

[0017] Figure 2 Differential scanning calorimetry (DSC) graphs of crystalline and amorphous ursodeoxycholic acid API powders.

[0018] Figure 3 PXRD diffraction patterns of amorphous ursodeoxycholic acid API at different storage times under accelerated conditions.

[0019] Figure 4 Comparison of related substances of amorphous ursodeoxycholic acid API prepared at different temperatures.

[0020] Figure 5 PXRD diffraction patterns of amorphous ursodeoxycholic acid API prepared by different cooling methods.

[0021] Figure 6 Comparison of dissolution curves of crystalline and amorphous ursodeoxycholic acid API powders.

[0022] Figure 7 Comparison of dissolution curves of ursodeoxycholic acid oral suspension in different particle size ranges.

[0023] Figure 8 Comparison of dissolution curves of ursodeoxycholic acid oral suspension with different types of suspending agents. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0025] In order to fully understand the content of the present invention, the embodiment content is divided into two parts: the first part is to prepare amorphous ursodeoxycholic acid API using hot melt extrusion technology; the second part is to prepare oral suspension using amorphous ursodeoxycholic acid API.

[0026] Example 1

[0027] The temperatures of different heating sections of the twin-screw extruder were set to 180°C, 190°C, 200°C, 200°C and 205°C, respectively, and the screw speed was 50 rpm.

[0028] After the temperature rises to the set value, the screw is started, 100g of ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve and then added to the extruder through a feeding hopper. The light yellow transparent extrudate is quickly cooled by a cooling roller and crushed into particles with a particle size of 2mm-3mm, and then crushed into amorphous ursodeoxycholic acid API powder with a particle size of 5~30μm by air flow.

[0029] Example 2

[0030] The temperatures of different heating sections of the twin-screw extruder were set to 190°C, 195°C, 200°C, 205°C and 210°C, respectively, and the screw speed was 100 rpm.

[0031] After the temperature rises to the set value, the screw is started, 50g of ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve and then added to the extruder through a feeding hopper. The light yellow transparent extrudate is quickly cooled by a cooling roller and crushed into particles with a particle size of 2mm-3mm. The amorphous ursodeoxycholic acid API powder with a particle size of 5~30μm is crushed by air flow.

[0032] Example 3 Quality evaluation and results of amorphous ursodeoxycholic acid raw material

[0033] 1. Powder X-ray Diffraction (PXRD) Analysis

[0034] The ursodeoxycholic acid amorphous powder prepared in Example 1 and the ursodeoxycholic acid raw material before treatment were subjected to PXRD measurement. The parameters were set as follows: working voltage 40 kV, current 150 mA, scanning step length 0.02°, 2-Theta range 5°~90°. The results are shown in the attached Figure 1 .

[0035] The results showed that the characteristic diffraction peaks of the crystals of the raw material drug in the hot-melt extrudate of ursodeoxycholic acid provided by the present invention all disappeared, indicating that ursodeoxycholic acid was in an amorphous state.

[0036] 2. Differential Scanning Calorimetry (DSC) Analysis

[0037] The amorphous ursodeoxycholic acid and crystalline ursodeoxycholic acid API prepared by hot melt extruder in Example 1 were subjected to differential scanning calorimetry (DSC) analysis. The initial temperature of the DSC instrument was set at 25°C, the end temperature was set at 300°C, and the heating rate was set at 10°C / min. The results are shown in the attached Figure 2 .

[0038] As can be seen from the figure, in the DSC graph of the amorphous ursodeoxycholic acid bulk drug provided by the present invention, the melting point endothermic peak (about 207°C) of the crystalline ursodeoxycholic acid disappears, and a glass transition peak appears at 107.7°C, indicating that the crystalline ursodeoxycholic acid has been transformed into an amorphous form. At the same time, it is shown that the amorphous ursodeoxycholic acid has a higher glass transition temperature and good physical stability.

[0039] 3. Accelerated stability evaluation

[0040] The amorphous ursodeoxycholic acid raw material prepared in Example 1 was spread flat on the bottom of a weighing bottle (thickness less than 3 mm), placed in a drug stability test box at a temperature of 40°C ± 2°C and a relative humidity of 75% ± 5%. After 3 months and 6 months, it was taken out for PXRD detection to determine whether the drug crystal form has changed. The results are shown in the attached Figure 3 .

[0041] The results showed that the amorphous ursodeoxycholic acid API prepared by the hot melt extrusion method still existed in an amorphous form after being placed under accelerated conditions for 6 months, and had no tendency to transform into a crystalline form, indicating that the ursodeoxycholic acid amorphous API provided by the present invention had good stability.

[0042] Comparative Example 1 Comparison of the results of preparing amorphous ursodeoxycholic acid raw materials by different methods.

[0043] Comparative method 1: Weigh about 1.0g of ursodeoxycholic acid raw material, dissolve it in 20ml of methanol, ethanol, acetone, glacial acetic acid and other organic solvents, add it dropwise into 200ml of purified water under magnetic stirring, filter the obtained raw material precipitate, and dry it at 40℃ with air blowing to obtain the product.

[0044] Comparative method 2: Weigh about 1.0 g of ursodeoxycholic acid raw material, dissolve it in 20 ml of methanol and ethanol respectively, and evaporate to dryness under reduced pressure at 40°C using a rotary evaporator to obtain the product.

[0045] Comparative method 3: Weigh about 1.0 g of ursodeoxycholic acid raw material, place it in a test tube, completely melt it in a 205°C oil bath, quickly cool it in an ice water bath, and then crush it to obtain the product.

[0046] Comparative method 4: Take about 20 g of ursodeoxycholic acid raw material and grind it in a ball mill for 2 hours.

[0047] Results: (1) Using method 1 (solvent-precipitation method), amorphous ursodeoxycholic acid API could not be prepared after trying various organic solvents; (2) Using method 2 (solvent-rotary evaporation method), only part of the ursodeoxycholic acid API prepared was converted into an amorphous form, and the purity was low; (3) Using method 3 (melting-quenching method), high-purity amorphous ursodeoxycholic acid API was prepared; (4) Method 4 (physical grinding method) failed to produce amorphous ursodeoxycholic acid API.

[0048] The results showed that among the various methods for preparing ursodeoxycholic acid amorphous powder, only the melt-quenching method successfully obtained high-purity ursodeoxycholic acid amorphous powder. However, this method is only suitable for small-scale preparation in the laboratory. Compared with the hot-melt extrusion method, the output is small and continuous production is not possible.

[0049] Comparative Examples 2~5 Comparison of preparations with different process parameters of hot melt extruder The twin-screw extruder was set at different extrusion temperatures and screw speeds as shown in the following table. After the temperature reached the set value, the screw was started, and the ursodeoxycholic acid API that had been crushed and passed through a 60-mesh sieve was added to the extruder through the feeding hopper. The state of the extrudate after cooling by the cooling roller was observed as shown in Table 1.

[0050] Table 1 Extruder process parameters and extrudate state

[0051] Process parameters Segment temperature 1 Segment temperature 2 Segment temperature 3 Segment temperature 4 Segment temperature 5 Screw speed Extrudate state Comparative Example 2 180 185 190 190 195 100 Too much torque, no extrusion Comparative Example 3 180 185 190 190 195 50 Milky white opaque Comparative Example 4 190 195 200 210 215 50 Yellow transparent Comparative Example 5 200 205 210 215 220 100 Poor delivery of raw materials Example 1 180 190 200 200 205 50 Transparent glass-like flakes Example 2 190 195 200 205 210 100 Transparent glass-like flakes

[0052] Comparison results:

[0053] According to Comparative Examples 2-3, when the hot melt heating cylinder segment temperature 5 (extrusion temperature) is lower than 200°C, the API is not fully melted, or cannot be extruded due to excessive torque, or can be extruded but the extrudate is uneven and cannot be completely transformed into a glassy state.

[0054] According to Comparative Example 4: When the barrel segment temperature 5 (extrusion temperature) is higher than 210°C, the ursodeoxycholic acid raw material changes color due to heat.

[0055] According to Comparative Example 5: When the temperature of segment temperature 1 is close to 200°C, the API begins to melt, causing the API to stick to the front end of the screw, increasing the difficulty of feeding.

[0056] The above comparative test shows that the reasonable setting of the step-by-step heating program is very critical for the successful preparation of ursodeoxycholic acid amorphous bulk drug. The differential method (the method is detailed in Example 10) is used to detect the related substances of ursodeoxycholic acid bulk drug in Comparative Example 4. Compared with Example 1, the size and number of impurity peaks are significantly increased. The comparison diagram is shown in the attached figure. Figure 4 .

[0057] Comparative Example 6

[0058] The temperatures of different heating sections of the twin-screw extruder were set to 180°C, 190°C, 200°C, 200°C and 205°C, respectively, and the screw speed was 50 rpm.

[0059] After the temperature reaches the set value, the screw is started, 50 g of ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve before being added to the extruder through a feeding hopper. The light yellow transparent extrudate is naturally cooled by air on a conveyor belt and then crushed into cylindrical particles with a length of 2 mm to 3 mm using a strand pelletizer.

[0060] Comparative Example 7

[0061] The temperatures of different heating sections of the twin-screw extruder were set to 180°C, 190°C, 200°C, 200°C and 205°C, respectively, and the screw speed was 50 rpm.

[0062] After the temperature reaches the set value, the screw is started, 50 g of ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve before being added to the extruder through a feeding hopper. The light yellow transparent extrudate is cooled in a water bath and crushed into cylindrical particles with a length of 2 mm to 3 mm using a strand pelletizer.

[0063] The raw material drug powder of Example 1 and the ursodeoxycholic acid particles prepared in Comparative Examples 6-7 were ground into fine powder and then subjected to PXRD detection and comparison. The results showed that a small amount of crystalline ursodeoxycholic acid still existed in the amorphous ursodeoxycholic acid raw material drug prepared by natural air cooling and water bath cooling, which was manifested in the PXRD diagram as the appearance of multiple crystalline characteristic 2θ diffraction peaks. The specific spectrum is shown in the attached Figure 5 .

[0064] Example 4 In vitro dissolution evaluation of amorphous ursodeoxycholic acid powder

[0065] Weigh about 250 mg of the amorphous ursodeoxycholic acid API prepared in Example 1, the low-purity amorphous ursodeoxycholic acid API prepared by method 2 (solvent-rotary evaporation method) in Comparative Example 1, and the crystalline ursodeoxycholic acid API before treatment, and put them into a dissolution cup filled with 900 ml of dissolution medium (pH 6.8 phosphate) respectively. Use the paddle method at a speed of 40 rpm. After the sample is added, the paddle shaft is immediately rotated to sample 2 ml at 5 min, 10 min, 15 min, 20 min, 30 min, 45 min, 60 min, 90 min and 120 min respectively. The sample is filtered through a 0.45 μm filter membrane, 0.5 ml of the initial filtrate is discarded, and the drug content in the sample solution is detected by high performance liquid chromatography, and the cumulative dissolution at each time point is calculated. The dissolution curve is shown in the attached Figure 6 .

[0066] The chromatographic conditions were as follows: detection wavelength UV-210 nm, chromatographic column Agilent Ecplise-XDB-C18 (250 mm × 4.6 mm, 5 μm), mobile phase acetonitrile-0.01 mol / L potassium dihydrogen phosphate (pH 2.0) = 50:50, flow rate 1.2 ml / min, injection volume 100 μl, and running time 8 minutes.

[0067] Depend on Figure 5As shown in the results, the cumulative dissolution rate of the high-purity amorphous ursodeoxycholic acid API prepared by the present invention in a phosphate medium with a pH of 6.8 for 2 hours increased by about 15% (56.8→63.4%) and 40% (56.8%→79.3%) compared with the low-purity amorphous ursodeoxycholic acid API and crystalline ursodeoxycholic acid API prepared by the solvent-rotary evaporation method, respectively.

[0068] Example 5-7 Preparation of Ursodeoxycholic Acid Oral Suspension with Different Particle Size Ranges

[0069] Examples 5 to 7 provide a method for preparing an ursodeoxycholic acid oral suspension, the main components of which include raw materials and excipients. The ursodeoxycholic acid amorphous powder with different particle sizes prepared in Example 1 is used as the raw material of the ursodeoxycholic acid oral suspension, and the excipients include a suspending agent, a pH regulator, a flavoring agent, an antibacterial agent, a deflocculant, and a solvent. The specific proportions and addition amounts of each component are shown in Table 2 below.

[0070] Table 2 Prescription table of Examples 4 to 6

[0071] Ingredient name effect Dosage (g) Ursodeoxycholic acid amorphous powder API 25 Microcrystalline Cellulose-Sodium Carboxymethyl Cellulose CL-611 Suspending Agents 10 Citric acid pH Adjusters 1.25 Sodium Citrate pH Adjusters 2.5 Xylitol Flavoring agents 160 Sodium Cyclamate Flavoring agents 2.5 Sweet orange flavor Flavoring agents 0.15 benzoic acid Antimicrobial agents 0.75 Sodium chloride Deflocculants 0.3 glycerin Solvents 50 Propylene glycol Solvents 5 Deionized water Solvents Moderate Set to - 500ml

[0072] The preparation method adopted in Example 5 is as follows:

[0073] 1) The amorphous ursodeoxycholic acid flakes are treated by air flow pulverization, the particle size D90 is 5-10 μm, the working pressure is 9 kg, and it is ready for use;

[0074] 2) Weigh the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose CL-611 complex and place it in 90% deionized water for high-speed homogenization for 5 minutes at a shear rate of 20 kr / min. After stirring for 2 hours, a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion is obtained;

[0075] 3) Add the prescribed amount of xylitol to the aqueous dispersion and stir in a 65°C water bath for 10 minutes until completely dissolved. Remove from the water bath and cool to room temperature. Add the prescribed amount of glycerol and propylene glycol and stir for 10 minutes. Then add the prescribed amount of sodium cyclamate, citric acid, sodium citrate, sodium chloride, sweet orange flavor, and benzoic acid and stir for 20 minutes.

[0076] 4) Add the prescribed amount of ursodeoxycholic acid amorphous powder (5-10 μm) to the above-mentioned liquid medicine, stir for 60 min, and then homogenize at high speed for 60 min at a shear rate of 5 kr / min. Add deionized water to make the volume to 500 ml, and vacuum degas for 2 h to obtain ursodeoxycholic acid oral suspension with a particle size D90 ranging from 1 to 10 μm.

[0077] The preparation method adopted in Example 6 is as follows:

[0078] 1) The amorphous ursodeoxycholic acid flakes are treated by air flow pulverization, the particle size D90 is 10-20 μm, the working pressure is 8 kg, and it is ready for use;

[0079] 2) Weigh the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose CL-611 complex and place it in 90% deionized water for high-speed homogenization for 10 minutes at a shear rate of 15 kr / min. After stirring for 1.5 hours, a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion is obtained;

[0080] 3) Add the prescribed amount of xylitol to the aqueous dispersion and stir in a 65°C water bath for 10 minutes until completely dissolved. Remove from the water bath and cool to room temperature. Add the prescribed amount of glycerol and propylene glycol and stir for 10 minutes. Then add the prescribed amount of sodium cyclamate, citric acid, sodium citrate, sodium chloride, sweet orange flavor, and benzoic acid and stir for 20 minutes.

[0081] 4) Add the prescribed amount of ursodeoxycholic acid amorphous powder (10-20 μm) to the above-mentioned liquid medicine, stir for 45 min, and then homogenize at high speed for 45 min at a shear rate of 8 kr / min. Add deionized water to make the volume to 500 ml, and vacuum degas for 2 h to obtain ursodeoxycholic acid oral suspension with a particle size D90 ranging from 1 to 10 μm.

[0082] The preparation method adopted in Example 7 is as follows:

[0083] 1) The amorphous ursodeoxycholic acid flakes are treated by air flow pulverization, the particle size D90 is 20-30 μm, the working pressure is 7 kg, and it is ready for use;

[0084] 2) Weigh the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose CL-611 complex and place it in 90% deionized water for high-speed homogenization for 15 minutes at a shear rate of 10 kr / min. After stirring for 1 hour, a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion is obtained;

[0085] 3) Add the prescribed amount of xylitol to the aqueous dispersion and stir in a 65°C water bath for 10 minutes until completely dissolved. Remove from the water bath and cool to room temperature. Add the prescribed amount of glycerol and propylene glycol and stir for 10 minutes. Then add the prescribed amount of sodium cyclamate, citric acid, sodium citrate, sodium chloride, sweet orange flavor, and benzoic acid and stir for 20 minutes.

[0086] 4) Add the prescribed amount of ursodeoxycholic acid amorphous powder (20-30 μm) to the above-mentioned liquid medicine, stir for 30 min, and then homogenize at high speed for 30 min at a shear rate of 10 kr / min. Add deionized water to make the volume to 500 ml, and vacuum degas for 2 h to obtain ursodeoxycholic acid oral suspension with a particle size D90 ranging from 1 to 10 μm.

[0087] Comparative Example 8

[0088] This comparative example provides a method for preparing an ursodeoxycholic acid oral suspension, wherein the prescription composition is the same as that of Example 5, and the preparation method is as follows:

[0089] 1) The amorphous ursodeoxycholic acid flakes are subjected to air flow pulverization treatment, the particle size D90 is 1-5 μm, the working pressure is 10 kg, and the mixture is set aside;

[0090] 2) Weigh the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose CL-611 complex and place it in 90% deionized water for high-speed homogenization for 10 minutes at a shear rate of 15 kr / min. After stirring for 1 hour, a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion is obtained;

[0091] Add the prescribed amount of xylitol to the aqueous dispersion and stir in a 65°C water bath for 10 minutes until completely dissolved, remove from the water bath and cool to room temperature, add the prescribed amount of glycerin and propylene glycol and stir for 10 minutes, then add the prescribed amount of sodium cyclamate, citric acid, sodium citrate, sodium chloride, sweet orange flavor, and benzoic acid and stir for 20 minutes;

[0092] 4) Add the prescribed amount of ursodeoxycholic acid amorphous powder (1-5 μm) to the above liquid medicine, stir for 30 min, then homogenize at high speed for 60 min, shear rate 10 kr / min, add deionized water to make the volume 500 ml, vacuum degas for 2 h, and obtain ursodeoxycholic acid oral suspension with a particle size D90 range of 45-750 nm. (Except step 1, the remaining steps are the same as Example 6)

[0093] Comparative Example 9

[0094] This comparative example provides an ursodeoxycholic acid oral suspension, wherein the prescription composition is the same as that of Example 5, and the preparation method is as follows:

[0095] 1) The amorphous ursodeoxycholic acid flakes are treated by air flow pulverization, the particle size D90 is 30~50μm, the working pressure is 2Kg, and it is ready for use;

[0096] 2) Weigh the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose CL-611 complex and place it in 90% deionized water for high-speed homogenization for 10 minutes at a shear rate of 15 kr / min. After stirring for 1 hour, a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion is obtained;

[0097] 3) Add the prescribed amount of xylitol to the aqueous dispersion and stir in a 65°C water bath for 10 minutes until completely dissolved. Remove from the water bath and cool to room temperature. Add the prescribed amount of glycerol and propylene glycol and stir for 10 minutes. Then add the prescribed amount of sodium cyclamate, citric acid, sodium citrate, sodium chloride, sweet orange flavor, and benzoic acid and stir for 20 minutes.

[0098] 4) Add the prescribed amount of ursodeoxycholic acid amorphous powder (1-5 μm) to the above-mentioned liquid medicine, stir for 30 min, and then homogenize at high speed for 30 min at a shear rate of 5 kr / min. Add deionized water to make the volume to 500 ml, and vacuum degas for 2 h to obtain ursodeoxycholic acid oral suspension with a particle size D90 ranging from 11-25 μm.

[0099] Example 8 Quality Evaluation of Ursodeoxycholic Acid Oral Suspension in Different Particle Size Ranges

[0100] (1) Particle size detection method: Instrument: Mastersizer 3000 particle size analyzer, wet method, measurement time 10 s, background time 10 s, shading range 7-8%, cycle number 3 times, stirring speed 1200 rpm, stirring time 2 min.

[0101] (2) Sedimentation volume ratio: The determination method is to take 50 ml of the suspension and place it in a stoppered measuring cylinder, seal it tightly, shake it vigorously for 1 minute, record the initial height H0 of the suspension, let it stand for 3 hours, record the final height H of the suspension, and calculate it according to the formula: Sedimentation volume ratio = H / H0. The sedimentation ratio is required to be > 0.9.

[0102] (3) Viscosity: Use American Brookfield DV-2T viscometer, rotor model No. 2, speed 100 rpm.

[0103] (4) Dissolution curve: Paddle method, pH 6.8 phosphate medium 900ml, rotation speed 40 rpm, use a dry syringe to draw about 5ml of ursodeoxycholic acid oral suspension and inject it between the paddle shaft and the dissolution cup, and take 2ml samples at 5min, 10min, 15min, 20min, 30min, 45min, 60min, 90min and 120min respectively. The sample was filtered through a 0.45μm filter membrane, and 0.5ml of the initial filtrate was discarded. The drug content in the sample solution was detected by high performance liquid chromatography, and the cumulative dissolution at each time point was calculated. The dissolution curves of suspension preparations in various particle size ranges and commercially available original preparations are compared in the attached Figure 7 The quality evaluation results are shown in Table 3 below.

[0104] Table 3 Quality evaluation results of ursodeoxycholic acid oral suspension in different particle size ranges

[0105] project Example 5 Example 6 Example 7 Comparative Example 8 Comparative Example 9 Original preparation Ursodeoxycholic acid API initial particle size D90 5~10μm 10~20μm 20~30μm 1~5μm 30~50μm N / A Ursodeoxycholic acid oral suspension particle size D90 1~10μm 1~10μm 1~10μm 500nm~5μm 11~25μm N / A Viscosity 109.8 107.5 110.4 285.1 167.2 202.4 Sedimentation volume ratio 0.99 1.0 0.99 0.75 0.99 1.00 Zeta potential (mV) -27.7 -28.2 -29.1 -3.5 -24.2 -26.5

[0106] It can be seen from the data in Table 3 that when the particle size of the ursodeoxycholic acid amorphous bulk drug is in the range of 5 to 30 μm (Examples 5 to 7), the particle size of the prepared oral suspension preparations is between 1 and 10 μm, and there is no difference in the sedimentation volume ratio and Zeta potential test results, indicating that the oral suspension preparations have good physical stability within this range. At the same time, the dissolution curve also shows that there is no significant difference in the in vitro dissolution of the oral suspension.

[0107] In Comparative Example 8, when the initial particle size D90 of the amorphous ursodeoxycholic acid raw material powder was in the range of 1 to 5 μm, after being treated by a homogenization process, part of the raw material had a particle size less than 1 μm. Due to the large specific surface area, the surface activation energy of the particles increased, and the stability was poor. After the suspension was allowed to stand for a period of time, flocculation and stratification occurred (no dissolution curve measurement was performed), and the Zeta potential value increased significantly.

[0108] In Comparative Example 9, when the initial API particle size was greater than 30 μm, the API particle size in the prepared suspension exceeded 10 μm. At this time, the in vitro dissolution curve showed that the dissolution rate was significantly slowed down, and the final dissolution value was less than 65%.

[0109] The dissolution rate and final dissolution of the ursodeoxycholic acid oral suspension prepared from the amorphous raw material provided by the invention are significantly better than those of the original preparation.

[0110] Comparative Examples 10-13

[0111] Comparative Examples 10 to 13 provide ursodeoxycholic acid oral suspensions prepared using suspending agents of different types and proportions. The raw material is ursodeoxycholic acid amorphous powder prepared by the method of Example 1. The specific proportions and addition amounts of each component are shown in the table below. The preparation method is the same as that of Example 6.

[0112] Table 4 Prescriptions for Comparative Examples 10 to 13 (Batch 500 ml)

[0113] Ingredient name Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Ursodeoxycholic acid amorphous powder 25 25 25 25 Microcrystalline Cellulose-Sodium Carboxymethyl Cellulose CL-611 NA NA 8.3 16.7 Microcrystalline Cellulose-Sodium Carboxymethyl Cellulose RC-591 10 NA NA NA Microcrystalline Cellulose-Sodium Carboxymethyl Cellulose RC-581 NA 10 NA NA Citric acid 1.25 1.25 1.25 1.25 Sodium Citrate 2.5 2.5 2.5 2.5 Xylitol 160 160 160 160 Sodium Cyclamate 2.5 2.5 2.5 2.5 Sweet orange flavor 0.15 0.15 0.15 0.15 benzoic acid 0.75 0.75 0.75 0.75 Sodium chloride 0.3 0.3 0.3 0.3 glycerin 50 50 50 50 Propylene glycol 5 5 5 5 Deionized water Moderate Moderate Moderate Moderate Set to 500ml 500ml 500ml 500ml

[0114] Example 9 Quality evaluation results of oral suspensions with different types and proportions of suspending agents.

[0115] The quality of the commercially available original preparation and the ursodeoxycholic acid oral suspension prepared in Comparative Examples 10 to 13 was evaluated in the same manner as in Example 7. The quality evaluation results are shown in Table 5 and the dissolution curves are shown in Attached Table 5. Figure 8 .

[0116] Table 5 Quality evaluation results of oral suspensions with different types and proportions of suspending agents

[0117] Detection items Example 6 Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Original preparation Viscosity (cP) 107.5 324.2 201.2 107.8 207.5 202.4 Sedimentation volume ratio 1.0 1.00 1.00 0.75 1.00 1.00 Zeta potential (mV) -28.2 -28.1 -26.7 -11.1 -27.9 -26.5

[0118] According to the data in the above table, under the premise of meeting the physical stability, the dissolution rate of Example 6 is faster than that of the commercially available original preparation and Comparative Examples 10, 11 and 13 (Comparative Example 12 showed flocculation and sedimentation, and the dissolution curve test was not performed). We selected the type of suspending agent with lower viscosity and the appropriate prescription ratio. The prepared suspension has good fluidity, which is more conducive to the scale-up of the production process, and has a smoother taste, which is convenient for quantitative administration and improves the compliance of drug administration.

[0119] Example 10 Study on the stability of ursodeoxycholic acid oral suspension.

[0120] 1. Freeze-thaw cycle test

[0121] The suspension samples prepared in Examples 5 to 7 were frozen in a -20°C environment for 2 days, and then placed in a 40°C oven for heat dissolution for two days, and the cycle was repeated 3 times. After the test was completed, the suspension was tested. Compared with time 0, the physical state of the suspension did not change, indicating that the suspension preparation had good physical stability under extreme conditions. The specific results are shown in Table 6 below.

[0122] Table 6 Freeze-thaw cycle test results of oral suspension

[0123] Test items / samples Characteristics Viscosity (cP) Sedimentation volume ratio Zeta potential (mV) Example 5 Milky white homogeneous suspension 108.6 0.99 -27.5 Example 6 Milky white homogeneous suspension 105.8 0.99 -28.1 Example 7 Milky white homogeneous suspension 109.4 1.0 -28.7

[0124] 2. Accelerated stability test

[0125] The samples prepared in Examples 5 to 7 were subjected to accelerated stability tests. According to the provisions of the 2020 edition of the Chinese Pharmacopoeia, Part IV, 9001, Stability Test Guidelines for Drug Substances and Preparations, the samples were placed under accelerated test conditions (40°C ± 2°C, relative humidity 75% ± 5%) for 3 and 6 months, and the properties, viscosity, pH, sedimentation volume ratio, Zeta potential, content, related substances, and cumulative dissolution of the samples were compared. The specific results are shown in Tables 7 to 9.

[0126] The content was detected by HPLC, and the chromatographic conditions were the same as those in Comparative Example 6. The related substance detection method was a differential detector, the detector temperature was 35°C, the chromatographic column was Agilent Ecplise-XDB-C18 (250mm×4.6mm, 5μm), the mobile phase was acetonitrile-0.78g / L sodium dihydrogen phosphate dihydrate (pH3.0)-methanol = 300:370:400, the flow rate was 0.8ml / min, the injection volume was 50μl, and the running time was 60 minutes.

[0127] Table 7 Results of accelerated test of oral suspension (Example 5)

[0128] Project / Time Point limit Day 0 March June Characteristics Milky white suspension Milky white suspension Milky white suspension Milky white suspension Viscosity 90~120 109.8 109.1 108.7 pH 4.0~5.0 4.51 4.50 4.50 Sedimentation volume ratio ≥0.90 0.99 0.99 0.98 Zeta Potential ≤-20mV -27.7 -27.8 -27.5 content(%) 90~110 99.5 98.9 99.2 Total impurities (%) ≤0.50 0.10 0.12 0.13 Cumulative dissolution (%) ≥70% 77.8 77.8 76.5

[0129] Table 8 Results of accelerated test of oral suspension (Example 6)

[0130] Project / Time Point limit Day 0 March June Characteristics Milky white suspension Milky white suspension Milky white suspension Milky white suspension Viscosity 90~120 107.5 107.8 107.4 pH 4.0~5.0 4.50 4.48 4.50 Sedimentation volume ratio ≥0.90 1.0 1.0 0.99 Zeta Potential ≤-20mV -28.2 -28.5 -27.7 content(%) 90~110 100.4 101.1 99.8 Total impurities (%) ≤0.50 0.07 0.08 0.12 Cumulative dissolution (%) ≥70% 76.5 76.1 75.2

[0131] Table 9 Results of accelerated oral suspension test (Example 7)

[0132] Project / Time Point limit Day 0 March June Characteristics Milky white suspension Milky white suspension Milky white suspension Milky white suspension Viscosity 90~120 110.4 108.4 109.5 pH 4.0~5.0 4.50 4.50 4.52 Sedimentation volume ratio ≥0.90 0.99 0.99 0.98 Zeta Potential ≤-20mV -29.1 -29.3 -28.4 content(%) 90~110 98.7 98.5 98.1 Total impurities (%) ≤0.50 0.07 0.10 0.11 Cumulative dissolution (%) ≥70% 74.2 73.8 73.3

[0133] The accelerated test data in Tables 7 to 9 show that the ursodeoxycholic acid oral suspension prepared by the present invention has good stability under accelerated conditions.

[0134] Those skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples; the present invention is intended to cover all substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An ursodeoxycholic acid oral suspension, comprising ursodeoxycholic acid, a suspending agent, a pH regulator, an antibacterial agent and a sweetener, characterized in that: Ursodeoxycholic acid is in an amorphous state, and the type of suspending agent is microcrystalline cellulose-sodium carboxymethyl cellulose complex; the dosage ratio of ursodeoxycholic acid to suspending agent is 3:1~1.5:

1.

2. The ursodeoxycholic acid oral suspension according to claim 1, characterized in that The particle size of the ursodeoxycholic acid amorphous raw material used is D 90 The range is 5~30μm.

3. The ursodeoxycholic acid oral suspension according to claim 1, characterized in that The particle size of the ursodeoxycholic acid amorphous raw material used is D 90 The range is 10~20μm.

4. The ursodeoxycholic acid oral suspension according to claim 1, characterized in that The particle size D of the ursodeoxycholic acid oral suspension 90 The range is 1~10μm.

5. The ursodeoxycholic acid oral suspension according to claim 1, characterized in that: The amorphous ursodeoxycholic acid bulk drug is prepared by a hot melt extruder.

6. The ursodeoxycholic acid oral suspension according to claim 5, characterized in that The hot melt extruder is a twin-screw extruder with a barrel temperature range of 180°C to 210°C and a screw speed of 50 to 100 rpm, followed by a cooling roller and a pulverizer.

7. The ursodeoxycholic acid oral suspension according to claim 1, characterized in that: The model of the microcrystalline cellulose-sodium carboxymethyl cellulose complex is CL-611.

8. A method for preparing ursodeoxycholic acid oral suspension, characterized in that: The steps include: 1) API pretreatment: The crystalline ursodeoxycholic acid API is crushed and passed through a 60-mesh sieve, and then hot-melt extruded, cooled, and crushed to obtain glassy flakes, which are then air-flow-pulverized to obtain amorphous ursodeoxycholic acid API with a particle size D90 ranging from 5 to 30 μm; 2) Weigh an appropriate amount of the prescribed amount of microcrystalline cellulose-sodium carboxymethyl cellulose complex, place it in deionized water and homogenize it at high speed for 5-15 minutes at a shear rate of 10-20 kr / min, and stir for 1-2 hours to obtain a fully swollen microcrystalline cellulose-sodium carboxymethyl cellulose aqueous dispersion; 3) Add the prescribed amount of antibacterial agent, pH adjuster, antiflocculant and flavoring agent to the aqueous dispersion, stir evenly, then add the prescribed amount of treated raw materials and stir evenly at a low speed; 4) Set the shear rate to 5-10 kr / min and perform high-speed homogenization for 30-60 min to obtain ursodeoxycholic acid oral suspension with a particle size D90 ranging from 1-10 μm.

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