A screening method for oral paclitaxel prescription

Abstract

The invention discloses a method for screening an oral paclitaxel prescription. The technical scheme comprises the following steps: step one, preliminary physical and chemical property determination of paclitaxel comprises: (1) apparent solubility investigation; (2) amorphous solubility investigation; (3) crystallization tendency determination; step two, preliminary carrier excipient screening comprises: (1) equilibrium solubility experiment; (2) supersaturation experiment; step three, paclitaxel SDDs prescription screening comprises: (1) spray drying; (2) preliminary evaluation of sample dissolution; (3) sample content determination; (4) sample thermal performance analysis; (5) thermogravimetric analysis; (6) powder X-ray diffraction; (7) powder dissolution; step four, selection of paclitaxel SDDs stability prescription. The invention has the advantages that exploratory attempts are made through equilibrium solubility experiments, supersaturation maintenance experiments and powder dissolution experiments, so that researchers have an accurate understanding of paclitaxel, and lay a foundation for the research of oral paclitaxel.

Description

Technical Field

[0001] The invention relates to the technical field of paclitaxel drug preparation, and in particular to a method for screening oral paclitaxel prescriptions. Background Art

[0002] Paclitaxel (PTX) is a natural secondary metabolite isolated and purified from the bark of Taxus chinensis. It belongs to the taxane monomer diterpene alkaloid compound. It is mainly suitable for ovarian cancer, breast cancer, head and neck cancer, non-small cell lung cancer, and has certain efficacy on prostate cancer, advanced Kaposi's sarcoma and pancreatic cancer. Therefore, paclitaxel is clinically recognized as one of the first choice of anti-cancer chemotherapy drugs, but due to the high lipophilicity and low water solubility of paclitaxel, its solubility in commonly accepted drug solvents such as polyethylene glycol 400, ethanol, propylene glycol, glycerol, etc. is also limited, which is also a barrier on the road of paclitaxel drug development.

[0003] The mainstream paclitaxel injections on the market are (BMS Company), (Ansutai Faμlding Company) and (Domestic) are all made of (polyethoxylated castor oil) and anhydrous ethanol (1:1, v / v) are mixed with a mixture of 6mg / ml paclitaxel to improve the solubility of paclitaxel, but polyoxyethyl castor oil releases histamine when degraded in vivo, which can cause more serious side effects such as allergic reactions, nephrotoxicity and neurotoxicity. Pre-desensitization treatment is required before clinical use, and containers or bags without plasticizers are also required to avoid the reaction of liquid with polyvinyl chloride (PVC) to generate diethyl phthalate (DEHP) to cause precipitation and cause toxicity. Therefore, new preparations that improve the solubility of paclitaxel, reduce the toxic and side effects of paclitaxel, and improve the efficacy of paclitaxel are increasingly attracting the attention of researchers. In recent years, through the continuous exploration of taxanes and the continuous improvement of preparation technology, new injection formulations such as paclitaxel liposomes, albumin-bound paclitaxel and paclitaxel micelles have been developed to reduce allergic reactions and reduce drug toxic and side effects.

[0004] Intravenous injection and oral administration are the two most commonly used routes of administration. The solubility of raw materials such as paclitaxel is very poor, and it is necessary to add enhancers, which may be harmful to the body and may cause irritation and severe allergic reactions. Oral paclitaxel has good safety and broad development prospects because it can reduce the use of enhancers.

[0005] Many attempts have been made to develop various oral dosage forms to increase the oral BA of PTX, including solid dispersions, microemulsions / nanoemulsions, micelles / nano-micelles, nanocrystals, liposomes, etc., among which the most widely used technology is solid dispersion (SD) technology. Solid dispersions are solid dispersions of one or more active ingredients in an inert carrier matrix, prepared by melting or solvent methods. Considering the physicochemical properties of paclitaxel (decomposition at 230°C, TGA results), melting (HEM) is not the first choice, and spray drying (SD) is an effective technology for preparing a production method to improve the solubility and BA of hydrophobic drugs. However, before conducting solid dispersion technology research and development, researchers need to accurately understand the characteristics of systemic paclitaxel and select the most appropriate paclitaxel prescription. Summary of the invention

[0006] In view of the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a method for screening oral paclitaxel prescriptions, which has the advantage of conducting exploratory attempts through equilibrium solubility experiments, supersaturation maintenance experiments and powder dissolution experiments, so that researchers can have an accurate understanding of the solubilization and supersaturation maintenance effects of paclitaxel, laying a foundation for subsequent research on oral paclitaxel.

[0007] The above technical objectives of the present invention are achieved through the following technical solutions:

[0008] A method for screening an oral paclitaxel prescription comprises the following steps:

[0009] Step 1: Determination of the preliminary physicochemical properties of paclitaxel:

[0010] (1) Apparent solubility investigation:

[0011] First, paclitaxel was placed in three centrifuge tubes, and equal amounts of 0.05M HCl, 50M phosphate buffer, and aqueous solution were added respectively; paclitaxel was weighed and placed in another centrifuge tube, and then a mixed solution of alcohol and water was added, vortexed and ultrasonicated for 30 minutes to fully disperse, and finally placed in a 37°C water bath shaker for 48 hours, and then sampled, centrifuged at 13,000 rpm for 5 minutes, and then an appropriate amount of supernatant was taken and diluted with methanol, and subjected to HPLC quantitative analysis;

[0012] (2) Investigation of amorphous solubility:

[0013] Take 0.05M HCl and 50M phosphate buffer respectively, add paclitaxel methanol solution to each, mix well, centrifuge at 13000 rpm for 1 min, take an appropriate amount of supernatant, dilute 10 times with methanol and perform HPLC quantitative analysis;

[0014] (3) Determination of crystallization trend:

[0015] Take a paclitaxel sample and spread it on a glass slide, heat it to 10°C above the melting point to make the paclitaxel sample fully melted, then quickly place it on a metal plate for quenching, observe it under a polarizing microscope to determine that it is amorphous, drop 50M phosphate buffer or 0.05M HCl into it to observe whether there is crystallization and the speed of crystallization;

[0016] Step 2: Preliminary screening of carrier excipients:

[0017] First, according to the results measured in step 1, a pre-carrier excipient combination is proposed, and a carrier excipient and a binary surfactant excipient combination are proposed;

[0018] (1) Equilibrium solubility experiment:

[0019] Weigh paclitaxel and place it in a centrifuge tube, then add 50M phosphate buffer containing a polymer pre-dissolved with a carrier excipient combination, vortex and ultrasonically treat for 30 minutes to fully disperse it, and finally place it in a 37°C water bath shaker for fixed-point sampling at 2, 6, 12, 24, and 48 hours, centrifuge at 13,000 speed for 5 minutes, take an appropriate amount of supernatant and dilute it with methanol, and perform HPLC quantitative analysis, repeat the experiment, and obtain the results of all carrier excipient combinations, select the best carrier excipient combination from the results, add active agent excipients on the basis of the carrier, and conduct the experiment under the same conditions;

[0020] (2) Supersaturation experiment:

[0021] Weigh the paclitaxel methanol solution, add 50M phosphate buffer in which the polymer of the carrier excipient combination is pre-dissolved to produce a supersaturated solution, place it in a 37°C water bath shaker for 5, 15, 30, 60, 120, 240 minutes and 48 hours, centrifuge at 3900 speed for 5 minutes, take an appropriate amount of supernatant and dilute it 1 times with methanol for HPLC quantitative analysis; select the best carrier excipient combination from the results, add the active agent excipient on the basis of the carrier, and conduct the experiment under the same conditions;

[0022] The combination of carrier and active agent was initially selected based on the results of equilibrium solubility experiment and supersaturation experiment;

[0023] Step 3: Screening of Paclitaxel SDDs prescriptions:

[0024] (1) Spray drying:

[0025] Component A: dissolve paclitaxel API in anhydrous ethanol;

[0026] Component B: dissolving the screened polymer of the carrier excipient combination in an ethanol solution;

[0027] The A component and the B component solutions were fully mixed to prepare a 5% (w / w) solution, and ultrasonically mixed for 5 minutes; a spray dryer was used to prepare a crude paclitaxel SDDs product, and the drying parameters were: inlet temperature 85°C, outlet temperature 55°C; solution feed rate: 8mL / min; atomization nitrogen pressure 0.1MPa; after preparation, the crude paclitaxel SDDs product was vacuum dried at 40°C overnight to remove residual solvent, and then the sample was placed at 4°C for use;

[0028] (2) Preliminary evaluation of sample dissolution:

[0029] Take the sample into a volumetric flask, gradually add 50M phosphate buffer, and observe the dissolution of the powder;

[0030] (3) Sample content determination:

[0031] Take the sample into a volumetric flask, dissolve it with methanol and make up to volume, mix it ultrasonically for 1 min, take an appropriate amount and dilute it 10 times with methanol and perform HPLC quantitative analysis;

[0032] (4) Analysis of thermal properties of samples:

[0033] The samples were placed in an aluminum pan and the thermal properties of the samples were analyzed using a differential scanning calorimeter. The parameters were heating from ambient temperature to 235 °C at a heating rate of 10 °C / min and a nitrogen flow rate of 40 mL / min.

[0034] (5) Thermogravimetric analysis:

[0035] Take the sample into a thermogravimetric analyzer, heat the sample to 400°C, obtain a weight-temperature relationship diagram, obtain the weight loss between 25 and 200°C, and analyze the sample decomposition temperature;

[0036] (6) Powder X-ray diffraction:

[0037] The PXRD pattern of the sample was obtained using an X-ray diffractometer. First, a 0.5 mm thick dry sample was placed in a silicon sample holder and placed in the diffractometer to complete the scan;

[0038] (7), powder dissolution:

[0039] The sample was placed in a centrifuge tube, and then 50 M phosphate buffer or 0.05 M HCl was added. After vortexing, ultrasonic treatment was performed for 30 min to allow it to be fully dispersed. Finally, it was placed in a 37°C water bath shaker. 400 μL of samples were taken at 15, 30, 60, 120, 240 min, 12, and 48 h. After centrifugation at 13,000 rpm for 5 min, an appropriate amount of supernatant was taken and diluted with methanol, and HPLC quantitative analysis was performed.

[0040] Step 4: Select the Paclitaxel SDDs Stability Formula:

[0041] The prescription was obtained according to step three, and stability experiments were carried out. The samples were stored at 40°C, 75% open and closed, and room temperature closed for 5 days, 10 days, 15 days, and 1 month. DSC and XRD were checked to evaluate the crystallinity of PTX, and HPLC was used for content determination.

[0042] Furthermore, in the apparent solubility study of step 1 (1), the amount of paclitaxel first taken was 10 mg, and the amounts of 0.05 M HCl, 50 M phosphate buffer, and aqueous solution were respectively 10 ml, wherein the pH value of 0.05 M HCl was 1.5, and the pH value of 50 M phosphate buffer was 6.5; the amount of paclitaxel weighed was 80 mg, the alcohol and water mixed solution was methanol / water (7:3) solution or ethanol / water (7:3) solution, and the amount of the alcohol and water mixed solution was 10 ml; and the sample volume after water bath was 500 μl.

[0043] Furthermore, in step 1 (2) amorphous solubility study, the amount of 0.05M HCl and 50M phosphate buffer used was 1 ml, the amount of paclitaxel methanol solution used was 20-40 μl, and the concentration was 50 mg / ml.

[0044] Furthermore, in the crystallization trend determination of step 1 (3), the heating temperature is 230° C. and maintained at 230° C. for 1 min.

[0045] Furthermore, in the equilibrium solubility experiment of step 2 (1), the amount of paclitaxel used was 10 mg, the amount of 50 M phosphate buffer used was 10 ml, and the pH value thereof was 6.5.

[0046] Furthermore, in the supersaturation experiment of step 2 (2), the concentration of paclitaxel methanol solution is 50 mg / ml, the amount of paclitaxel methanol solution is 100 μl, the amount of 50 M phosphate buffer is 5 ml, and a supersaturated solution with a concentration of 100 μg / mL is prepared.

[0047] Further, in step 3 (1) spray drying:

[0048] Component A: 200 mg of paclitaxel API and 10 ml of anhydrous ethanol;

[0049] Component B: The amount of the polymer of the carrier excipient combination is 800 mg, the amount of the ethanol solution is 10 ml, and the ratio of anhydrous ethanol to water in the ethanol solution is 4:6.

[0050] Furthermore, in the thermogravimetric analysis of step three (5), the heating rate is 10° C. / min.

[0051] Furthermore, in step three (6) X-ray diffraction, the sample was scanned at a current of 40 mA and a tension of 40 kV.

[0052] Furthermore, in step three (6) X-ray diffraction, the scanning range is 5-40°, the diffraction angle is 2°, the step length is 0.026°, and the scanning speed is 0.146° per second.

[0053] In summary, the present invention has the following beneficial effects:

[0054] 1. Through preliminary research on the physical and chemical properties of paclitaxel, the apparent solubility, amorphous solubility, and crystallization trend of paclitaxel were studied, and the dissolution and supersaturation maintenance of paclitaxel (PTX) in various combination solutions were investigated. Although it is not equivalent to the actual ASD powder dissolution or tablet dissolution, it can intuitively screen out which carrier excipients have potential solubilization function, providing clues and ideas for improving the solubility of paclitaxel.

[0055] 2. Preliminary screening of carrier excipients: Based on the strategy of developing PTX ternary solid dispersion oral preparations, excipient screening of polymer carrier and surfactant combination was carried out through equilibrium solubility and supersaturation experiments under phosphate buffer (PBS, pH 6.5) conditions, and analyzed by HPLC, differential scanning calorimetry, thermogravimetric analysis, powder X-ray diffraction, powder dissolution and other analytical methods to provide a reference for studying and screening paclitaxel prescriptions with high apparent solubility / dissolution rate.

[0056] 3. Through the screening of paclitaxel SDDs prescriptions, based on the screening results of carrier excipients, combined with the understanding and experiments of the solubility characteristics of the excipients, the main carrier excipients were formulated, and the samples were initially prepared by spray drying. The samples were also analyzed by HPLC, differential scanning calorimetry, thermogravimetric analysis, powder X-ray diffraction, powder dissolution and other analytical methods to screen out the optimal prescription. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is a polarization diagram of the crystallization trend of PTX crystal powder (PBS test group) before heating.

[0058] Figure 2 This is a polarization diagram of the crystallization trend of PTX crystal powder (PBS test group) after heating, melting and quenching.

[0059] Figure 3 This is a polarization diagram of the crystallization trend of an amorphous PTX sample after being dropped into a PBS solution and immersed for 1 hour.

[0060] Figure 4 This is a polarization diagram of the crystallization trend of PTX crystal powder (HCL detection group) before heating.

[0061] Figure 5This is a polarization diagram of the crystallization trend of PTX crystal powder (HCL detection group) after heating, melting and quenching.

[0062] Figure 6 This is a polarization diagram of the crystallization trend of an amorphous PTX sample after being dropped into HCL solution and immersed for 1 hour.

[0063] Figure 7 It is the solubility curve diagram of the experimental groups S0 to S9.

[0064] Figure 8 It is the solubility curve diagram of the experimental group S6 and S8 combination and the original surfactant excipient combination.

[0065] Fig. 9 It is the supersaturation curve diagram of the experimental group S0~S9.

[0066] Fig.10 It is the supersaturation curve diagram of the experimental group S6 and S8 combination and the surfactant excipient combination.

[0067] Fig.11 This is a graph showing the dissolution of samples of prescriptions SDD1 to SDD6.

[0068] Fig.12 This is the sample dissolution diagram of SDD3.

[0069] Fig.13 It is a curve chart of DSC experimental results of the corresponding raw materials of prescriptions SDD1 to SDD6.

[0070] Fig.14 It is a curve chart of TGA experimental results of the corresponding raw materials of prescriptions SDD1 to SDD6.

[0071] Fig.15 It is a curve chart of DSC experimental results of samples with prescriptions SDD1 to SDD6.

[0072] Fig.16 It is a curve chart of TGA experimental results of samples with prescriptions SDD1 to SDD6.

[0073] Fig.17 This is a graph showing the preliminary evaluation of the dissolution of samples of prescriptions SDD1 to SDD6.

[0074] Fig.18 This is a diagram showing the dissolution results of the prescription SDD3 sample in 100 μL PBS (pH 6.5) solution.

[0075] Fig.19 This is a graph showing the powder dissolution test results of formulations SDD1 to SDD6 under PBS (pH 6.5) conditions.

[0076] Fig. 20This is a comparison chart of the appearance and dissolution of prescriptions SDD3 and SDD6.

[0077] Fig.21 This is the XRPD comparison chart of the stable sample with crystalline peaks in SDD3 and SDD6, PTX raw material and SLS auxiliary material. DETAILED DESCRIPTION

[0078] In order to make the purpose, technical solution and advantages of the present invention more clear, the solution proposed by the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. According to the following description, the advantages and features of the present invention will be more clear.

[0079] Example:

[0080] A method for screening an oral paclitaxel prescription comprises the following steps:

[0081] The abbreviation of paclitaxel is PTX, and the abbreviation of phosphate buffered saline is PBS.

[0082] Step 1: Determination of the preliminary physicochemical properties of paclitaxel:

[0083] (1) Apparent solubility investigation:

[0084] 10 mg of PTX was weighed and placed in three 15 mL centrifuge tubes, and 10 mL of 0.05 M HCl (pH 1.5), 50 M phosphate buffer (PBS, pH 6.5), and aqueous solution were added respectively; 80 mg of PTX was weighed and placed in 15 mL centrifuge tubes, and then 10 mL of methanol / water (7:3) solution or 10 mL of ethanol / water (7:3) solution was added, vortexed and ultrasonically treated for 30 min to fully disperse, and finally placed in a 37°C water bath shaker for 48 h, 500 μL of the sample was taken, and centrifuged at 13,000 rpm for 5 min, and an appropriate amount of supernatant was taken and diluted 1 times (or other appropriate multiples) with methanol, and HPLC quantitative analysis was performed.

[0085] (2) Investigation of amorphous solubility:

[0086] 20-40 μL of 50 mg / mL PTX methanol solution was added to 1 mL of 0.05 M HCl (pH 1.5) and 50 M PBS (pH 6.5), respectively. The mixture was mixed and centrifuged at 13,000 rpm for 1 min. An appropriate amount of the supernatant was diluted 10 times with methanol and subjected to HPLC quantitative analysis.

[0087] (3) Crystallization trend:

[0088] Take a small amount of PTX sample and spread it on a glass slide. Heat it to 10°C above the melting point, that is, about 230°C, and maintain it for 1 min to make it fully melted. Then quickly place it on a metal plate to quench it. Observe it under a polarizing microscope to determine that it is amorphous. Drop 50M PBS (pH 6.5) or 0.05M HCl (pH 6.5) into it to observe whether there is crystallization and the speed of crystallization.

[0089] Summary of preliminary physicochemical properties of paclitaxel:

[0090] 1. Basic physical and chemical information of paclitaxel, see Table 1 for details.

[0091]

[0092]

[0093] Table 1

[0094] 2. Polarization diagram of the crystallization trend of PTX in 0.05M HCl and 50M PBS solutions.

[0095] PBS test group:

[0096] A1: Figure 1 As shown, the crystallization trend of PTX crystal powder before heating is polarized.

[0097] A2: If Figure 2 As shown, the crystallization trend polarization of PTX crystal powder after heating, melting and quenching.

[0098] A3: Figure 3 As shown, the polarization trend of the crystallization trend of the amorphous PTX sample after PBS solution was dropped into it and immersed in it for 1 hour.

[0099] HCl test group:

[0100] B1: If Figure 4 As shown, the crystallization trend of PTX crystal powder before heating is polarized.

[0101] B2: If Figure 5 As shown, the crystallization trend polarization of PTX crystal powder after heating, melting and quenching.

[0102] B3: If Figure 6 As shown, the polarization trend of the crystallization trend of the amorphous PTX sample after PBS solution was dropped into it and immersed in it for 1 hour.

[0103] Result analysis:

[0104] Paclitaxel has a complex ring structure with a large condensed taxane ring in the center, surrounded by several hydrophobic functional groups that shield many polar oxygen-containing groups. It has a high molecular weight and lacks protonable groups, so its water solubility is poor. The pKa of paclitaxel is 11.99, indicating that it is a difficultly protonated / deprotonated compound, so its solubility in strong acids or bases is not easy to increase. In formulation design, changing the pH value will not have additional effects.

[0105] The results of solubility experiments showed that the solubility of PTX in the three aqueous solutions was lower than 1 μg / mL, among which the solubility in pure water PBS (pH 6.5) was close to about 0.3 μg / mL, and the solubility in acid was slightly higher, about 0.7 μg / mL.

[0106] The crystallization trend of amorphous paclitaxel was observed by polarizing microscope. The results showed that the crystallization trend of amorphous PTX in aqueous solution was relatively slow, and no crystals were formed within 1 hour. Comparing the solubility test results of amorphous PTX and crystals, the solubility ratios of amorphous PTX and crystals were 91.9 (PBS, pH 6.5) and 57.3 (0.05M HCl, pH 1.5), respectively.

[0107] Step 2: Preliminary screening of carrier excipients:

[0108] Based on the overall strategy for developing PTX ternary solid dispersion oral preparations, the carrier excipient combination before formulating SDDs was formulated with reference to relevant public literature and patents (see Table 2), and the carrier and binary surfactant excipient combination is shown in Table 3. Preliminary excipient screening of polymer carrier and surfactant combination was carried out through equilibrium solubility and supersaturation experiments under 50M PBS (pH 6.5). The structures of candidate polymers and surfactants are shown in Table 4, i.e., experimental groups S0 to S8.

[0109] name S0 S1 S2 S3 S4 S5 S6 S7 S8 PTX 10 10 10 10 10 10 10 10 10 HPMCAS(M) - 30 30 - - 60 60 - - PVPVA(64) - - - 30 30 - - 60 60 TPGS - 5 - 5 - 150 - 150 - Soluplus - - 5 - 5 - 150 - 150

[0110] Table 2

[0111] Note: HPMCAS: Hydroxypropyl methylcellulose succinate, PVPVA: Copovidone, TPGS: Vitamin E polyethylene glycol succinate, Soluplus: Polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer.

[0112] name S6-1 S6-2 S8-1 S8-2 PTX 10 10 10 10 HPMCAS(M) 60 60 - - PVPVA(64) - - 60 60 Soluplus 100 100 100 100 SLS 50 - 50 - Tween80 - 50 - 50

[0113] Table 3

[0114] Note: SLS: Sodium dodecyl sulfate, Tween80: Tween 80.

[0115]

[0116]

[0117] Table 4

[0118] (1) Equilibrium solubility experiment:

[0119] 10 mg PTX was weighed and placed in a 15 mL centrifuge tube, and then 10 mL of PBS (pH 6.5) solution containing pre-dissolved polymers of various prescription amounts was added. After vortexing, ultrasonic treatment was performed for 30 min to allow it to be fully dispersed. Finally, it was placed in a 37°C water bath shaker and 400 μL of samples were taken at fixed points at 2, 6, 12, 24, and 48 h. After centrifugation at 13,000 rpm for 5 min, an appropriate amount of supernatant was taken and diluted 1-fold (or other appropriate multiples) with methanol and subjected to HPLC quantitative analysis. n=3 for all experiments.

[0120] According to the results of the equilibrium solubility experiment, a solubility curve is drawn. For details, see Figure 7 .

[0121] Conclusion: From Figure 7 It can be seen that the high surfactant ratio combination S5-S8 has a significant improvement in the solubilization of PTX, among which the combination of S6 and S8 containing Soluplus grafted polymer has the best effect.

[0122] The equilibrium solubility experiment was repeated based on the carrier and primary surfactant excipient combinations based on the S6 and S8 combinations.

[0123] According to the results of the equilibrium solubility experiment, a solubility curve is drawn. For details, see Figure 8 .

[0124] Conclusion: From Figure 8 The results show that the two combinations of SLS surfactants, S6-1 and S8-1, are superior to the combination containing Tween 80.

[0125] (2) Supersaturation experiment:

[0126] 100 μL of 50 mg / mL PTX methanol solution was added to 5 mL of PBS (pH 6.5) solution containing pre-dissolved S0-S8 to produce a supersaturated solution with a theoretical concentration of 100 μg / mL, and placed in a 37°C water bath shaker for 5, 15, 30, 60, 120, 240 min and 48 h, centrifuged at 3900 rpm for 5 min, and then an appropriate amount of supernatant was taken and diluted 1-fold with methanol for HPLC quantitative analysis. n=3 for all experiments.

[0127] According to the experimental results of supersaturation, the supersaturation curve is drawn. Fig. 9 .

[0128] Conclusion: From Fig. 9It can be seen that the high surfactant ratio combinations S5~S8 have a significant improvement in maintaining the supersaturation of PTX, among which the combinations of S6 and S8 containing Soluplus grafted polymers are the best, which is consistent with the conclusion of the equilibrium solubility experiment.

[0129] Based on the combination of S6 and S8, a carrier and a two-component surfactant excipient combination were performed, and the supersaturation experiment was carried out again.

[0130] According to the experimental results of supersaturation, the supersaturation curve is drawn. Fig.10 .

[0131] Conclusion: From Fig.10 The results show that the two combinations of SLS surfactants, S6-1 and S8-1, are better than the combination containing Tween 80, which is consistent with the conclusion of the equilibrium solubility experiment.

[0132] Summary of experimental results:

[0133] The solubility results of PTX in different solvents are shown in Table 5.

[0134]

[0135]

[0136] Table 5

[0137] Conclusion: In summary, the equilibrium solubility and supersaturation experiments are only preliminary investigations on the dissolution and supersaturation maintenance of PTX in various combination solutions, which cannot be equated with the actual ASD powder dissolution or tablet dissolution. However, from the experimental results, it can be seen that: ①, there is indeed a lot of room for PTX solubilization, and the experimental solubility ratio of S8-1 to crystalline PTX is 291.6 (at 37°C); ②, whether HPMCAS or the combination of PVPVA and TPGS, the effect of solubilizing PTX and maintaining supersaturation is not ideal.

[0138] Step 3: Screening of Paclitaxel SDDs prescriptions:

[0139] (1) Spray drying:

[0140] Component A: Dissolve 200 mg of API drug in 10 mL of anhydrous ethanol.

[0141] Component B: Dissolve a total of 800 mg of the polymer in the prescribed ratio in 10 mL of anhydrous ethanol / water (4:6); fully mix the A and B solutions to prepare a 5% (w / w) solution, and ultrasonically mix for 5 minutes.

[0142] The paclitaxel ASD was prepared using a spray dryer Yamato ADL 311s with an inlet temperature of 85°C and an outlet temperature of 55°C; solution feed rate: 8 mL / min; atomization nitrogen pressure 0.1 MPa; after preparation, the paclitaxel SSDs were vacuum dried at 40°C overnight to remove residual solvent, and then the samples were placed at 4°C for use.

[0143] (2) Preliminary evaluation of SD sample dissolution:

[0144] Weigh 1 mg of each SD sample into a transparent liquid phase vial, gradually add 50-100 μL PBS (pH 6.5) solution, and observe the dissolution of the powder.

[0145] (3) Determination of SD sample content:

[0146] Weigh 20 mg of the prescription sample into a 10 mL volumetric flask, dissolve it with methanol and make up to volume. After ultrasonic mixing for 1 min, take an appropriate amount and dilute it 10 times with methanol and perform HPLC quantitative analysis.

[0147] (4) Analysis of thermal properties of samples:

[0148] The thermal properties of the samples were analyzed using a TA DSC Q2000 differential scanning calorimeter. About 1 to 5 mg of the sample was weighed into a Tzero aluminum pan and heated from ambient temperature to 235°C at a heating rate of 10°C / min and a nitrogen flow rate of 40 mL / min.

[0149] (5) Thermogravimetric analysis:

[0150] Using a TGA Discovery Q50 thermogravimetric analyzer, about 1-5 mg of the sample was placed in a platinum pan and covered with a lid, and heated to 400°C (heating rate: 10°C / min). The weight-temperature graph was analyzed using Trios software to calculate the weight loss between 25 and 200°C and analyze the sample decomposition temperature.

[0151] (6) Powder X-ray diffraction:

[0152] The PXRD patterns of the samples were obtained using a high-resolution X'pert X-ray diffractometer. A dried sample of about 0.5 mm thickness was placed in a silicon sample holder, placed in the diffractometer, and scanned at a current of 40 mA and a tension of 40 kV, with a scanning range of 5-40° (diffraction angle of 2°), a step size of 0.026°, and a scanning speed of 0.146° per second.

[0153] (7), powder dissolution:

[0154] Weigh 10 mg of SDD sample and place it in a 15 mL centrifuge tube, then add 10 mL of PBS (pH 6.5) or 0.05 M HCl (pH 1.5) solution, vortex and ultrasonically treat for 30 min to fully disperse it, finally place it in a 37°C water bath shaker, take 400 μL of samples at 15, 30, 60, 120, 240 min and 12, 48 h, centrifuge at 13,000 rpm for 5 min, take an appropriate amount of supernatant and dilute it 1-fold (or other suitable multiples) with methanol and perform HPLC quantitative analysis.

[0155] (8) Experimental results:

[0156] According to the screening results of carrier excipients in step 2, combined with the experience of excipient solubility characteristics and simple small-scale experiments, we fully considered: ①, Soluplus grafted polymer itself is a polymer material that dissolves slowly in aqueous solution and is easy to agglomerate, and is not suitable for large-scale application in ASD prescriptions; ②, HPMCAS dissolves slower than PVPVA in aqueous solution, and when combined with Soluplus grafted polymer, it increases the difficulty of solution clarification. Based on the above factors, the SDDs prescription screening combination with common PVPVA as the main carrier excipient and 20% PTX loading is proposed, as shown in Table 6.

[0157] prescription SDD1 SDD2 SDD3 SDD4 SDD5 SDD6 PTX 200 200 200 200 200 200 PVPVA(64) 800 700 700 700 700 - HPMCAS - - - - - 700 Soluplus - 100 - 70 - - SLS - - 100 30 - 100 TPGS - - - - 100 - Total 1000 1000 1000 1000 1000 1000

[0158] Table 6

[0159] Spray drying results: The yield of the spray-dried samples of each prescription is shown in Table 7.

[0160]

[0161]

[0162] Table 7

[0163] Sample dissolution results: Sample dissolution results for prescriptions SDD1 to SDD6 are shown in Fig.11 .

[0164] Only the prescription SDD3 could be quickly dissolved into a clear solution in 50 μL solution, while the other prescriptions were poorly soluble in 100 μL solution and could not be completely dissolved even after being diluted to 1.5 mL.

[0165] The same method was used to further confirm the solubility limit of the prescription SDD3 in PBS (pH 6.5) solution. The results showed that 50 mg of the prescription SDD3 sample could still be dissolved and clarified in 100 μL solution by needle stirring. Fig.12, but the viscosity is relatively high (the solution was diluted and quantified by HPLC, the concentration was 108 mg / mL), and its solubility is 4000 times that of the amorphous PTX (29 μg / mL). The dissolution of prescription SDD3 is shown in Fig.12 .

[0166] Thermal performance analysis results:

[0167] 1. DSC test results of the corresponding raw materials of prescriptions SDD1~SDD6, see Fig.13 .

[0168] 2. DSC test results of samples of prescriptions SDD1 to SDD6, see Fig.15 .

[0169] Thermogravimetric analysis results:

[0170] 1. TGA test results of the corresponding raw materials of prescriptions SDD1~SDD6, see Fig.14 .

[0171] 2. TGA test results of samples of prescriptions SDD1 to SDD6, see Fig.16 .

[0172] Powder dissolution results:

[0173] The powder dissolution comparison experiment of SDD1~SDD6 in PBS (pH6.5) was carried out. The results were consistent with the above experimental results. SDD3 (PTX:PVPVA:SLS=2:7:1) could achieve 100% solubility, followed by prescription SDD6 (PTX:HPMCAS:SLS=2:7:1), with a solubility of about 30%. They can maintain supersaturation capacity for more than 48h, see for details. Fig.17 .

[0174] Comparative experimental groups S9 and S10 were designed, and their compositions are shown in Table 8.

[0175] name S9 S10 PTX 10 10 HPMCAS(M) - 30 PVPVA(64) 30 - SLS 5 5

[0176] Table 8

[0177] The effect of maintaining supersaturation of PTX in PBS (pH 6.5) solution was investigated. The results showed that the supersaturation maintenance effect of the S9 solution combination sample was not good, which was inconsistent with the dissolution results of the SDD3 spray-dried sample. The dissolution results of the S10 solution combination sample and the SDD6 spray-dried sample were similar, and the supersaturation was better maintained. Fig.18 .

[0178] Further comparative experiments on the dissolution of SDD3 and SDD6 powders in 0.05 M HCl (pH 1.5) were carried out, and the dissolution results of SDD3 and SDD6 powders in PBS (pH 6.5) were compared and analyzed. Fig.19 .

[0179] The results showed that SDD3 was only about 20% in an acidic environment, and its supersaturation maintenance effect after 12 hours was worse than that of SDD6.

[0180] In summary, SDD3 and SDD6 have their own advantages in solubilizing PTX and maintaining supersaturation, and they are currently the two most ideal amorphous PTX formulations.

[0181] Step 4: Select the paclitaxel SDDs stability formula:

[0182] In this embodiment, according to the screening results of step three, two prescriptions, SDD3 and SDD6, are temporarily selected for short-term accelerated stability experiments, in order to provide data reference for further optimizing the prescription. The stability study plan is as follows: the samples are stored at 40°C, 75% open and closed, and room temperature closed for 5 days, 10 days, 15 days, and 1 month, and DSC and XRD are checked to evaluate the crystallinity of PTX, and HPLC is used for content determination. The results are shown in Table 9.

[0183]

[0184]

[0185]

[0186] Table 9

[0187] Comparison of the appearance and dissolution of prescriptions SDD3 and SDD6, see Fig. 20 .

[0188] The XRPD comparison of the stable samples with crystalline peaks in SDD3 and SDD6 and PTX raw materials and SLS auxiliary materials is shown in Fig.21 .

[0189] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0190] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for screening oral paclitaxel prescriptions, characterized in that: The following steps are involved: Step 1: Determination of the preliminary physicochemical properties of paclitaxel: (1) Apparent solubility investigation: First, paclitaxel was placed in three centrifuge tubes, and equal amounts of 0.05M HCl, 50M phosphate buffer, and aqueous solution were added respectively; paclitaxel was weighed and placed in another centrifuge tube, and then a mixed solution of alcohol and water was added, vortexed and ultrasonicated for 30 minutes to fully disperse, and finally placed in a 37°C water bath shaker for 48 hours, and then sampled, centrifuged at 13,000 rpm for 5 minutes, and then an appropriate amount of supernatant was taken and diluted with methanol, and subjected to HPLC quantitative analysis; (2) Investigation of amorphous solubility: Take 0.05M HCl and 50M phosphate buffer respectively, add paclitaxel methanol solution to each, mix well, centrifuge at 13000 rpm for 1 min, take an appropriate amount of supernatant, dilute 10 times with methanol and perform HPLC quantitative analysis; (3) Determination of crystallization trend: Take a paclitaxel sample and spread it on a glass slide, heat it to 10°C above the melting point to make the paclitaxel sample fully melted, then quickly place it on a metal plate for quenching, observe it under a polarizing microscope to determine that it is amorphous, drop 50M phosphate buffer or 0.05M HCl into it to observe whether there is crystallization and the speed of crystallization; Step 2: Preliminary screening of carrier excipients: First, according to the results measured in step 1, a pre-carrier excipient combination is proposed, and a carrier excipient and a binary surfactant excipient combination are proposed; (1) Equilibrium solubility experiment: Weigh paclitaxel and place it in a centrifuge tube, then add 50M phosphate buffer containing a polymer pre-dissolved with a carrier excipient combination, vortex and ultrasonically treat for 30 minutes to fully disperse it, and finally place it in a 37°C water bath shaker for fixed-point sampling at 2, 6, 12, 24, and 48 hours, centrifuge at 13,000 speed for 5 minutes, take an appropriate amount of supernatant and dilute it with methanol, and perform HPLC quantitative analysis, repeat the experiment, and obtain the results of all carrier excipient combinations, select the best carrier excipient combination from the results, add active agent excipients on the basis of the carrier, and conduct the experiment under the same conditions; (2) Supersaturation experiment: Weigh the paclitaxel methanol solution, add 50M phosphate buffer in which the polymer of the carrier excipient combination is pre-dissolved to produce a supersaturated solution, place it in a 37°C water bath shaker for 5, 15, 30, 60, 120, 240 minutes and 48 hours, centrifuge at 3900 speed for 5 minutes, take an appropriate amount of supernatant and dilute it 1 times with methanol for HPLC quantitative analysis; select the best carrier excipient combination from the results, add the active agent excipient on the basis of the carrier, and conduct the experiment under the same conditions; The combination of carrier and active agent was initially selected based on the results of equilibrium solubility experiment and supersaturation experiment; Step 3: Screening of Paclitaxel SDDs prescriptions: (1) Spray drying: Component A: dissolve paclitaxel API in anhydrous ethanol; Component B: dissolving the screened polymer of the carrier excipient combination in an ethanol solution; The A component and the B component solutions were fully mixed to form a 5% (w / w) solution, and ultrasonically mixed for 5 minutes; a spray dryer was used to prepare a crude paclitaxel SDDs product, and the drying parameters were: inlet temperature 85°C, outlet temperature 55°C; solution feed rate: 8mL / min; atomization nitrogen pressure 0.1MPa; After preparation, the crude paclitaxel SDDs were dried under vacuum at 40°C overnight to remove the residual solvent, and then the samples were kept at 4°C for future use; (2) Preliminary evaluation of sample dissolution: Take the sample into a volumetric flask, gradually add 50M phosphate buffer, and observe the dissolution of the powder; (3) Sample content determination: Take the sample into a volumetric flask, dissolve it with methanol and make up to volume, mix it ultrasonically for 1 min, take an appropriate amount and dilute it 10 times with methanol and perform HPLC quantitative analysis; (4) Analysis of thermal properties of samples: The samples were placed in an aluminum pan and the thermal properties of the samples were analyzed using a differential scanning calorimeter. The parameters were heating from ambient temperature to 235 °C at a heating rate of 10 °C / min and a nitrogen flow rate of 40 mL / min. (5) Thermogravimetric analysis: Take the sample into a thermogravimetric analyzer, heat the sample to 400°C, obtain a weight-temperature relationship diagram, obtain the weight loss between 25 and 200°C, and analyze the sample decomposition temperature; (6) Powder X-ray diffraction: The PXRD pattern of the sample was obtained using an X-ray diffractometer. First, a 0.5 mm thick dry sample was placed in a silicon sample holder and placed in the diffractometer to complete the scan; (7), powder dissolution: The sample was placed in a centrifuge tube, and then 50 M phosphate buffer or 0.05 M HCl was added. After vortexing, ultrasonic treatment was performed for 30 min to allow it to be fully dispersed. Finally, it was placed in a 37°C water bath shaker. 400 μL of samples were taken at 15, 30, 60, 120, 240 min, 12, and 48 h. After centrifugation at 13,000 rpm for 5 min, an appropriate amount of supernatant was taken and diluted with methanol, and HPLC quantitative analysis was performed. Step 4: Select the Paclitaxel SDDs Stability Formula: According to the prescription obtained in step 3, a stability test was conducted, and the samples were stored at 40°C, 75% open and closed, and room temperature closed for 5 days, 10 days, 15 days, and 1 month, and DSC and XRD were examined to evaluate the crystallinity of PTX, and HPLC was used for content determination; In the apparent solubility study of step 1 (1), the amount of paclitaxel taken first is 10 mg, and the amount of 0.05M HCl, 50M phosphate buffer, and aqueous solution taken is 10 ml respectively, wherein the pH value of 0.05M HCl is 1.5, and the pH value of 50M phosphate buffer is 6.5; the amount of paclitaxel taken is 80 mg, and the alcohol and water mixed solution is methanol / water solution, and the volume ratio of methanol / water is 7:3, or ethanol / water solution, and the volume ratio of ethanol / water is 7:3, and the amount of alcohol and water mixed solution taken is 10 ml; the sample volume after water bath is 500 μl; In step 3 (1) spray drying: Component A: 200 mg of paclitaxel API and 10 ml of anhydrous ethanol; Component B: The amount of the polymer of the carrier excipient combination is 800 mg, the amount of the ethanol solution is 10 ml, and the ratio of anhydrous ethanol to water in the ethanol solution is 4:

6.

2. The method for screening an oral paclitaxel prescription according to claim 1, characterized in that: In step 1 (2) amorphous solubility study, the amount of 0.05M HCl and 50M phosphate buffer used was 1 ml, the amount of paclitaxel methanol solution used was 20-40 μl, and the concentration was 50 mg / ml.

3. The method for screening an oral paclitaxel prescription according to claim 2, characterized in that: In step 1 (3) crystallization trend determination, the heating temperature is 230° C. and maintained at 230° C. for 1 min.

4. The method for screening an oral paclitaxel prescription according to claim 1, characterized in that: In the equilibrium solubility experiment of step 2 (1), the amount of paclitaxel used was 10 mg, the amount of 50 M phosphate buffer used was 10 ml, and the pH value thereof was 6.

5.

5. The method for screening an oral paclitaxel prescription according to claim 4, characterized in that: In the supersaturation experiment of step 2 (2), the concentration of paclitaxel methanol solution is 50 mg / ml, the amount of paclitaxel methanol solution is 100 μl, the amount of 50 M phosphate buffer is 5 ml, and a supersaturated solution with a concentration of 100 μg / mL is prepared.

6. The method for screening an oral paclitaxel prescription according to claim 1, characterized in that: In the thermogravimetric analysis of step 3 (5), the heating rate is 10° C. / min.

7. The method for screening an oral paclitaxel prescription according to claim 6, characterized in that: In step three (6) X-ray diffraction, the sample was scanned at a current of 40 mA and a tension of 40 kV.

8. The method for screening an oral paclitaxel prescription according to claim 7, characterized in that: In step three (6) X-ray diffraction, the scanning range is 5-40°, the diffraction angle is 2°, the step length is 0.026°, and the scanning speed is 0.146° per second.

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