A method for improving the stability of difacillin acetate preparation

Abstract

The present invention relates to a method for improving the stability of a difalin acetate preparation. The method comprises mixing auxiliary materials in a solvent, adjusting the pH to 3.0-4.0, and then adding difalin acetate to dissolve the mixture; diluting the resulting solution with a solvent to obtain a difalin acetate solution; introducing a protective gas into the resulting difalin acetate solution to ensure that the dissolved oxygen content in the difalin acetate solution is ≤1.0 mg / L; filtering the resulting solution, filling the container, and introducing a protective gas into the container to control the residual oxygen content in the container to ≤3.0%; and sealing, sterilizing, and leak-checking the resulting semi-finished product to obtain a difalin acetate preparation. The present invention prepares a terminally sterilized difalin acetate preparation by controlling the pH range of the preparation solution, as well as controlling the nitrogen flow and nitrogen filling during the preparation process and the filling and nitrogen filling process. This significantly improves the quality of the preparation, reduces the impurity content, ensures a high sterility level, and improves the adverse effects of high temperature on the preparation.

Description

Technical Field

[0001] The present invention relates to the technical field of biomedicine, and in particular to a method for improving the stability of a difaxian acetate preparation. Background Art

[0002] Difaridine acetate, whose chemical name is 4-amino-1-(p-phenylalanyl-D-phenylalanyl-D-leucyl-D-lysyl)piperidine-4-carboxylic acid acetate, is a κ opioid receptor (KOR) agonist clinically used to treat moderate to severe pruritus associated with chronic kidney disease (CKD-aP) in adults undergoing hemodialysis (HD).

[0003] Difatamide acetate is a synthetic peptide with a single stereoisomer. It is a white to off-white powder and exists in the form of acetate. Its structural formula is shown below:

[0004]

[0005] Currently, a diffuran acetate formulation, diffuran acetate injection, is available in the US and EU, but no formulation is currently available in China. However, the US-listed formulation is an injection prepared using a sterile filtration process, which carries certain sterility risks. The EU-listed formulation is terminally sterilized and therefore contains high levels of impurities.

[0006] Therefore, there is an urgent need to provide a method that can effectively inhibit the degradation process of diflucan acetate, reduce the degradation of diflucan acetate during production, storage and transportation, and improve the stability of the drug. Summary of the Invention

[0007] To solve the above-mentioned technical problems, the present invention provides a method for improving the stability of difacillin acetate preparations, filling a gap in domestic preparations. Compared with existing difacillin acetate preparations on the market, the present invention effectively inhibits the degradation process of difacillin acetate by controlling the pH value of the solution during preparation and the protective gas process, reducing the degradation of difacillin acetate during production, storage, and transportation, and improving the stability of the drug. Therefore, the preparation provided by the method of the present invention has a low impurity content, a high sterility assurance factor, and can improve the adverse effects of high temperature on the preparation, greatly improving the stability of the preparation during transportation, storage, and use, and enhancing the safety of difacillin acetate injection preparations, with obvious clinical advantages.

[0008] The present invention is achieved through the following technical solutions:

[0009] The object of the present invention is to provide a method for improving the stability of difacillin acetate preparation, comprising the following steps:

[0010] (1) Mix the excipients in a solvent, adjust the pH to 3.0-4.0, and then add difamethicone acetate to dissolve;

[0011] (2) diluting the solution obtained in step (1) with a solvent to obtain a difacillin acetate solution;

[0012] (3) introducing a protective gas into the difamethicone acetate solution obtained in step (2) so that the dissolved oxygen content in the difamethicone acetate solution is ≤1.0 mg / L;

[0013] (4) filtering the solution obtained in step (3), filling the container, and filling the container with protective gas to control the residual oxygen content in the container to ≤3.0%;

[0014] (5) The semi-finished product obtained in step (4) is sealed, sterilized and leak-checked to obtain the difamethicone acetate preparation.

[0015] In one embodiment of the present invention, in step (1), the auxiliary material is selected from one or more of sodium chloride, potassium chloride, sodium acetate, ammonium acetate and potassium acetate.

[0016] In one embodiment of the present invention, in step (1), the solvent is selected from one or more of water for injection, propylene glycol for injection and glycerol for injection.

[0017] In one embodiment of the present invention, in step (1), the pH is adjusted by an acetic acid solution with a concentration of 0.5 mol / L to 5 mol / L.

[0018] In one embodiment of the present invention, in step (2), the concentration of the difaxian acetate solution is 40 μg / mL to 60 μg / mL (calculated as difaxian).

[0019] In one embodiment of the present invention, in step (3) and step (4), the protective gas is selected from nitrogen and / or carbon dioxide.

[0020] In one embodiment of the present invention, in step (3) and step (4), the flow rate of the protective gas is 2.0m 3 / h~3.0m 3 / h.

[0021] In one embodiment of the present invention, in step (4), the container is a sterilized and depyrogenated container.

[0022] In one embodiment of the present invention, in step (5), the sterilization conditions are: sterilization at 115°C to 121°C for ≥12 min; specifically, sterilization at 121°C for 12 min to 15 min or sterilization at 115°C for ≥30 min.

[0023] In one embodiment of the present invention, in step (5), the leak detection is colored water leak detection.

[0024] The above technical solution of the present invention has the following advantages over the prior art:

[0025] The present invention prepares a terminally sterilized difaxian acetate injection by controlling the pH range of the preparation liquid, and controlling the preparation processes such as nitrogen aeration during the preparation process and nitrogen filling during the potting process. The quality of the preparation is significantly improved, the impurity content is low, the sterility assurance level is high, and the adverse effects of high temperature on the preparation can be alleviated. DETAILED DESCRIPTION

[0026] The present invention will be further described below with reference to specific examples so that those skilled in the art can better understand the present invention and implement it, but the examples are not intended to limit the present invention.

[0027] The present invention provides a method for improving the stability of a difaxian acetate preparation, comprising the following main steps:

[0028] (1) dissolving the active substance of difamethicone acetate in a solution containing all excipients, adjusting the pH value to 3.0-4.0 by adding acetic acid solution, and diluting with water for injection to obtain the required weight, and passing protective gas;

[0029] (2) sterilizing and filtering the final solution;

[0030] (3) Fill the solution into a sterilized and depyrogenated borosilicate glass ampoule, fill it with protective gas, control residual oxygen, and seal it with a sealant;

[0031] (4) sterilizing and leak-checking the sealed semi-finished preparation to obtain the diffuran acetate preparation.

[0032] In the difacillin acetate preparation of the present invention, the concentration of difacillin acetate (calculated as difacillin) can be 40 μg / mL to 60 μg / mL. In addition, sodium chloride is selected as an isotonic agent, and the sodium chloride concentration can be 6.5 mg / mL to 7.9 mg / mL. Sodium acetate is selected as a buffer, and the sodium acetate concentration can be 2.25 mg / mL to 2.75 mg / mL. Acetic acid or glacial acetic acid is further used as a pH regulator, and the acetic acid or glacial acetic acid is prepared into an acetic acid solution for further use, and the acetic acid concentration can be 0.5 mol / L to 5 mol / L. The pH regulator adjusts the pH of the drug solution to a range of 3.0 to 4.0.

[0033] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, and the materials and reagents used are all commercially available unless otherwise specified.

[0034] The difacillin acetate used in the examples of the present invention is sourced from Suzhou Tianma Pharmaceutical Group Tianji Biopharmaceutical Co., Ltd., and its registration number on the AEP registration platform of the Center for Drug Evaluation of the State Food and Drug Administration is Y20240000239, with main batch numbers being 0920221201R and 0920230602.

[0035] Example 1: Study on protective gas process

[0036] (1) Preparation of diffuran acetate solution:

[0037] 1) Weigh 12.0 g of glacial acetic acid, dilute with water for injection, make up to 100 mL, and mix well to obtain a 2 mol / L acetic acid solution.

[0038] 2) Take 1600 mL of water for injection, dissolve 14.40 g of sodium chloride and 5.00 g of sodium acetate in the water, add 2 mol / L acetic acid solution, and adjust the pH of the solution to 4.5.

[0039] 3) Add 0.12 g of difacillin acetate to the solution obtained in step 2), stir to dissolve, and then add water for injection to 2000 mL to obtain difacillin acetate solution.

[0040] (2) Protective gas process and potting

[0041] Table 1

[0042] batch number 24060901 24060902 24060903 24060904 24060905 Nitrogen flow process (dissolved oxygen) N / A N / A N / A Dissolved oxygen ≤ 1 mg / L Dissolved oxygen ≤ 1 mg / L Nitrogen filling process (residual oxygen) N / A Residual oxygen about 10% Residual oxygen about 3% N / A Residual oxygen about 3%

[0043] According to the design in Table 1 above, the protective gas process research is carried out, as follows:

[0044] Take 300 mL of the difaxian preparation obtained in step (1), directly fill about 1 mL into a 2 mL ampoule, seal it with a melt, and record the sample batch number as 24060901;

[0045] Take 300 mL of the difaxian preparation obtained in step (1) and fill it into a 2 mL ampoule with a filling volume of about 1 mL. Then, fill the ampoule with nitrogen until the residual oxygen content is about 10%, seal it with a seal, and record the sample batch number as 23060902;

[0046] Take 300 mL of the difalin acetate preparation obtained in step (1) and fill it into a 2 mL ampoule with a filling volume of about 1 mL. Then, fill the ampoule with nitrogen until the residual oxygen content is about 3%, seal it with a seal, and record the sample batch number as 24060903;

[0047] Take 300 mL of the diffuran acetate preparation obtained in step (1), introduce nitrogen into the solution until the dissolved oxygen is ≤1 mg / L, and then fill about 1 mL into a 2 mL ampoule, seal it with a sealant, and record the sample batch number as 24060904;

[0048] Take 300 mL of the diffuran acetate preparation obtained in step (1), introduce nitrogen into the solution until the dissolved oxygen content is ≤1 mg / L, and then fill about 1 mL into a 2 mL ampoule. Then, fill the ampoule with nitrogen until the residual oxygen content is about 3%, seal it with a seal, and record the sample batch number as 24060905.

[0049] (3) Sterilization

[0050] After the sealing, batches 24060901 to 24060905 of the samples were sterilized at 121° C. for 15 min, and diffuran acetate preparations with different protective gas processes were prepared.

[0051] The pH value and HPLC analysis of related substances were performed on samples of different protective gas processes. The results are shown in Table 2 below.

[0052] Table 2

[0053]

[0054]

[0055] The above results show that both nitrogen aeration of the diffuran acetate solution to reduce dissolved oxygen and nitrogen filling during filling to reduce residual oxygen in the container can improve the quality and stability of the preparation to a certain extent. The combined effect of the two is more significant. Specifically, nitrogen aeration of the solution to control dissolved oxygen ≤1mg / L and nitrogen filling during filling to control residual oxygen ≤3.0% can achieve better quality for this product.

[0056] Example 2 Study on pH of the drug solution

[0057] (1) Preparation of diffuran acetate solution:

[0058] 1) Weigh 24.0 g of glacial acetic acid, dilute with water for injection, make up to 200 mL, and mix well to obtain a 2 mol / L acetic acid solution.

[0059] 2) Dissolve 3.60 g of sodium chloride and 1.25 g of sodium acetate in each of 7 400 mL portions of water for injection. Add 2 mol / L acetic acid solution according to the table below to adjust the pH of the solution to the value in Table 3. Then, add 0.029 g of difacillin acetate to each portion. After stirring to dissolve, add more water for injection to 500 mL. This yields 7 batches of solutions with different pH values ​​(24061601 to 24061607).

[0060] Table 3

[0061] batch number 24061601 24061602 24061603 24061604 24061605 24061606 24061607 Adjust pH No adjustment pH 5.5 pH 5.0 pH 4.5 pH 4.0 pH 3.5 pH 3.0

[0062] (2) Potting:

[0063] The drug solutions of different pH values ​​obtained in step (1) were filled in a volume of about 1 mL per vial and sealed.

[0064] (3) Sterilization:

[0065] After the sealing, batches 24061601 to 24061607 of samples were sterilized at 121° C. for 15 min, and difaxian acetate preparations with different pH values ​​were prepared.

[0066] The samples with different pH values ​​were subjected to pH detection and HPLC analysis of related substances. The results are shown in Table 4 below.

[0067] Table 4

[0068]

[0069]

[0070] The above results show that when the solution pH is adjusted to 4.0 or below, the purity exceeds 99.0%, and the RRT1.5 impurities and total impurities are at low levels. After high temperature and light exposure, they are also lower than other batches of samples under the same conditions. Therefore, the preferred pH range for the drug solution is 3.0-4.0.

[0071] Example 3

[0072] (1) Preparation of diffuran acetate solution:

[0073] 1) Weigh 120 g of glacial acetic acid, dilute with room temperature water for injection, add water to 1 L, and mix well to obtain a 2 mol / L acetic acid solution.

[0074] 2) Weigh 24 kg of room temperature water for injection into the dispensing tank, weigh 216.0 g of sodium chloride and 75.0 g of sodium acetate, dissolve them in water, add 2 mol / L acetic acid solution, adjust the solution pH to 3.5, then add 1.5 g of diflanyl acetate (calculated as diflanyl), stir to dissolve, and add water for injection to 30 L; introduce nitrogen into the solution until the dissolved oxygen is ≤1.0 mg / L, with a nitrogen flow rate of 2.0-3.0 m 3 / h.

[0075] (2) Filtration and potting

[0076] The drug solution was filtered through a 0.22 μm polyvinylidene fluoride (PVDF) filter element and then filled into a 2 mL medium borosilicate glass ampoule at a volume of 1.05 mL to 1.15 mL. Nitrogen was then filled in front and back to control the residual oxygen to ≤3%.

[0077] (3) Sterilization and leak detection

[0078] The sealed samples were sterilized at 121°C for 15 min and tested for leaks using colored water.

[0079] (5)Visual inspection

[0080] Eliminate unqualified products such as bottles without caps or poorly capped bottles, bottles with unqualified filling quantities, bottles with glass chips, fibers, color spots and other foreign matter, bottles with scratches, and bottles that are dirty or broken;

[0081] (6) Labeling, boxing, and packaging are completed, and the acetic acid diffuran preparation is ready, with the batch number marked as 24100801.

[0082] The samples were subjected to pH detection and HPLC analysis of related substances. The results are shown in Table 5 below.

[0083] Table 5

[0084]

[0085]

[0086] The above results show that the preparations prepared according to the process have a small number of impurities, low impurities, and little change in impurities after various influencing factors, long-term conditions and accelerated conditions. Even after 6 months of acceleration, the total impurities do not exceed 0.5%. The quality of the preparations is stable and of good quality.

[0087] Example 4

[0088] Three batches of samples were prepared according to the following process: 24070801, 24070901, and 24071001.

[0089] (1) Preparation of diffuran acetate solution:

[0090] 1) Weigh 12.0 g of glacial acetic acid, dilute with water for injection, make up to 100 mL, and mix well to obtain a 2 mol / L acetic acid solution.

[0091] 2) Dissolve 21.60 g of sodium chloride and 7.50 g of sodium acetate in 2400 mL of water for injection. Add 2 mol / L acetic acid solution to adjust the pH of the solution to approximately 3.5. Then, add 0.175 g of diflanyl acetate. After stirring to dissolve, add more water for injection to 3000 mL. Bubble nitrogen into the solution until the dissolved oxygen level is ≤1.0 mg / L to obtain diflanyl acetate solution.

[0092] (2) Filtration and potting:

[0093] The drug solution (partial, about 300 mL) was filled into a 2 mL medium borosilicate glass ampoule at a filling volume of about 1.1 mL, and nitrogen was added to the ampoule until the residual oxygen content was about 3%, and then the ampoule was sealed by fusion.

[0094] (3) Sterilization:

[0095] About 300 sealed samples were sterilized at 121°C for 15 min, and the difaxian acetate preparation was prepared.

[0096] The EU marketed preparation (trade name The impurity levels of the preparations (purchased from Shanghai Zhongzheyuan Biopharmaceutical Co., Ltd.) were compared with those of multiple batches of preparations prepared in small batches using the process of the present invention under light and high temperature conditions. The results are shown in Table 6. It can be clearly seen that the quality of the preparations of the present invention is stable and superior.

[0097] Table 6

[0098]

[0099]

[0100] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for improving the stability of difacillin acetate preparation, characterized in that: The following steps are involved: (1) Mix the excipients in a solvent, adjust the pH to 3.0-4.0, and then add difamethicone acetate to dissolve; (2) diluting the solution obtained in step (1) with a solvent to obtain a difacillin acetate solution; (3) introducing a protective gas into the difamethicone acetate solution obtained in step (2) so that the dissolved oxygen content in the difamethicone acetate solution is ≤1.0 mg / L; (4) filtering the solution obtained in step (3), filling the container, and filling the container with protective gas to control the residual oxygen content in the container to ≤3.0%; (5) The semi-finished product obtained in step (4) is sealed, sterilized and leak-checked to obtain the difamethicone acetate preparation.

2. The method according to claim 1, characterized in that In step (1), the auxiliary material is selected from one or more of sodium chloride, potassium chloride, sodium acetate, ammonium acetate and potassium acetate.

3. The method according to claim 1, characterized in that In step (1), the solvent is selected from one or more of water for injection, propylene glycol for injection and glycerol for injection.

4. The method according to claim 1, wherein In step (1), the pH is adjusted by an acetic acid solution having a concentration of 0.5 mol / L to 5 mol / L.

5. The method according to claim 1, wherein In step (2), the concentration of the difacillin acetate solution is 40 μg / mL to 60 μg / mL.

6. The method according to claim 1, characterized in that In step (3) and step (4), the protective gas is selected from nitrogen and / or carbon dioxide.

7. The method according to claim 1, characterized in that In step (3) and step (4), the flow rate of the protective gas is 2.0m 3 / h~3.0m 3 / h.

8. The method according to claim 1, characterized in that In step (4), the container is a sterilized and depyrogenated container.

9. The method according to claim 1, characterized in that In step (5), the sterilization conditions are: sterilization at 115°C to 121°C for ≥12 min.

10. The method according to claim 1, characterized in that In step (5), the leak detection is a colored water leak detection.

Images