A GLP-1 polypeptide microneedle patch and its preparation method

Abstract

This invention discloses a GLP-1 peptide drug microneedle and its preparation method. The microneedle is composed of PVP, NVP, a photoinitiator, and a GLP-1 receptor agonist. The preparation method includes two steps: material preparation and peptide microneedle patch preparation. First, a certain amount of PVP is dissolved in NVP to prepare a solution with appropriate specific gravity and viscosity. Then, the photoinitiator and GLP-1 receptor agonist are added to the solution to form a liquid system that is as uniformly suspended as possible. Second, the suspension is filled into a microneedle mold, and NVP is polymerized into solid PVP by ultraviolet light irradiation. Under the constraint of the mold, the solid PVP forms the geometric shape of the microneedle. Subsequently, a small amount of NVP is spread evenly on the backing layer of the microneedle and covered with a plastic film. Ultraviolet light irradiation is applied again to crosslink the plastic film with the PVP microneedle, and the microneedle is then peeled out of the mold. The advantage of this application is that it uses PVP to prepare an NVP solution with suitable specific gravity and viscosity, so that the subsequently added drug is uniformly suspended in the solution, thereby improving the uniformity of drug loading on microneedles and increasing the drug loading capacity, which is beneficial to improving the efficacy and consistency of drug efficacy.

Description

Technical Field

[0001] This invention relates to the field of pharmaceutical technology, specifically to a GLP-1 polypeptide microneedle patch and its preparation method. Background Technology

[0002] Currently, microneedle patches, as an innovative drug delivery system, have received widespread attention. Through the tiny cone-shaped microneedles on them, drugs are delivered directly to the superficial layers beneath the skin, enabling rapid, convenient, and painless drug delivery. However, microneedle patches also have some limitations.

[0003] Overall, the main reasons why drug microneedles have not yet been commercialized are their small drug loading capacity, poor drug loading uniformity, complex preparation technology that makes mass production difficult, and severe lack of biosafety excipients.

[0004] This invention utilizes NVP to dissolve or suspend drugs, and under the catalysis of a photoinitiator and the constraint of a microneedle negative mold, polymerizes NVP into PVP solid microneedles. The significant advantages of this method are: firstly, the preparation process is simple, yielding drug microneedles in tens of minutes, while almost all known processes require more than 24 hours to complete; secondly, the main excipient, PVP, is a very safe and biodegradable material, already widely used in drug preparation. The drawback of this method is that most drugs have low solubility in NVP, therefore the drug loading of microneedles made from homogeneous solutions of drugs and NVP does not reach therapeutic doses. Therefore, it is necessary to improve the drug loading of microneedles obtained by this method and ensure the uniformity of the drug loading meets the requirements of current drug regulatory regulations. Summary of the Invention

[0005] The objective of this invention is to increase the drug loading capacity of microneedles and ensure that the uniformity of the drug loading capacity meets the requirements of current drug management regulations.

[0006] The objective reality of using NVP as a solvent to dissolve drugs is that NVP has very low solubility for many drugs. Therefore, microneedles made from homogeneous, clear drug-containing solutions have a relatively small drug loading capacity. Once the NVP solution reaches saturation, the excess drug forms a solid suspension with the NVP. Using this suspension as a starting material significantly increases the drug loading capacity of microneedles. However, NVP has a specific gravity of 1.04 (25°C), while most solid drugs have a higher specific gravity than NVP. Therefore, the drug in the suspension generally settles, resulting in highly uneven drug content across different parts of the suspension. Microneedles made from suspensions with uneven drug content have very poor drug loading uniformity.

[0007] There are two kinetic reasons why suspended matter in a solution may or may not settle: First, the buoyancy of the solution on the suspended matter is not equal to the Earth's gravity. When the specific gravity of the suspended matter is greater than or less than the specific gravity of the solution, the suspended matter will settle or float. The specific gravity of the substance is a measure of this relationship. Second, when the force exerted by the solvent on the surface of the suspended matter is equal to or greater than the Earth's gravity or buoyancy, the suspended matter will remain stationary in the solution. The viscosity of the solution is a measure of this relationship.

[0008] Therefore, adjusting the specific gravity and viscosity of the solution is one of the measures to improve drug loading and ensure drug loading uniformity. For pharmaceutical formulations, it is also essential to minimize the types of materials involved and to ensure maximum safety. Under ultraviolet light irradiation, NVP polymerizes into PVP. PVP was one of the first biosafe substances approved as a pharmaceutical excipient, with a specific gravity of 1.144. The viscosity of a PVP aqueous solution at a given concentration increases rapidly with the degree of polymerization (molecular weight) of PVP. Therefore, adding a certain amount of PVP to NVP achieves the purpose of adjusting the specific gravity and viscosity of the solution. The added PVP, together with the PVP subsequently polymerized under light irradiation, constitutes the microneedle matrix without creating any new types of excipients.

[0009] Thus, the inventor's conception has achieved a logical closed loop, and its feasibility has been verified through the following experiments.

[0010] The technical solution and specific steps adopted in this invention are as follows:

[0011] (a) Solution preparation:

[0012] a) Dissolve polyvinylpyrrolidone (PVP) in N-vinylpyrrolidone (NVP) to prepare a solution with a specific gravity and viscosity;

[0013] b) Dissolve a certain amount of photoinitiator in the above solution;

[0014] c) Add the GLP-1 receptor agonist to the above solution to prepare a homogeneous suspension of the GLP-1 receptor agonist;

[0015] (II) Microneedle Preparation:

[0016] d) Fill the micropores of the microneedle mold with a uniform suspension of GLP-1 receptor agonist under vacuum, and remove excess suspension.

[0017] e) Ultraviolet light irradiation causes the liquid NVP in the micropores to polymerize into solid PVP microneedles;

[0018] f) Spread a small amount of NVP containing a photoinitiator on the needle surface of the microneedle mold;

[0019] g) Lay a layer of plastic film flat on the NVP liquid film and press it lightly;

[0020] h) Ultraviolet light irradiation causes NVP in the interlayer to polymerize into PVP, and tightly crosslinks the drug-containing PVP microneedles and plastic film.

[0021] i) Extract GLP-1 peptide microneedles from the mold.

[0022] Preferably, the GLP-1 receptor agonist is one of liraglutide, exenatide, or smegglutide.

[0023] Preferably, the N-vinylpyrrolidone (NVP) added in step f) is a photoinitiator with a concentration of 1.5% w / v.

[0024] Furthermore, the height of the microneedles is 150-2000 μm, optimized to 900 μm.

[0025] Furthermore, the microneedle is shaped like a cone, mostly a square pyramid, a cone, or a hexagonal pyramid. Preferably, the microneedle is shaped like a square pyramid with a base side length of 300-550 μm.

[0026] The advantages of this invention compared to the prior art are:

[0027] 1. Novel Microneedle Patch Structure: This invention provides a GLP-1 peptide microneedle patch having a substrate and a microneedle array. These microneedles are cone-shaped structures made of polymer materials, including a mixture of polyvinylpyrrolidone (PVP), N-vinylpyrrolidone (NVP), a photoinitiator, and a GLP-1 receptor agonist. Compared to conventional microneedle patch structures, this design can provide better drug loading capacity (especially uniformity of drug loading) and delivery efficiency (especially uniformity of efficacy).

[0028] 2. Optimization of Preparation Method: This invention provides an optimized preparation method, specifically including solution preparation and peptide microneedle patch preparation steps. By adjusting the concentration of the polymer material, the concentration of the photoinitiator, and process parameters such as ultraviolet irradiation time and temperature, uniform distribution and curing of the drug in the microneedles can be achieved. This optimized preparation method can improve the quality and consistency of the microneedle patch.

[0029] 3. Improved drug loading capacity and uniformity: The microneedle patch design and preparation method in this invention considers the interaction between the drug and the NVP solvent. By adjusting the specific gravity and viscosity of the solvent, the drug is uniformly suspended in the solution, avoiding drug sedimentation and floating. This can improve the drug loading capacity and uniformity of the microneedle patch, promoting the consistency and convergence of drug efficacy.

[0030] 4. Advantages in Applicability and Economy: The materials and processes used in this invention offer advantages in applicability and economy. Polyvinylpyrrolidone (PVP) and N-vinylpyrrolidone (NVP) are common and low-cost polymer materials, and the use of photoinitiators makes the curing process faster. This makes the preparation process industrially scalable and facilitates market promotion.

[0031] In summary, compared with the prior art, the advantages of this application lie in providing a novel microneedle patch structure and an optimized preparation method to improve drug loading, uniformity, and consistency of efficacy. Furthermore, the materials and process conditions used in this invention offer advantages in terms of applicability and economy. Attached Figure Description

[0032] Figure 1 Optical photograph of the liraglutide microneedles prepared in Example 1;

[0033] Figure 2 This is an enlarged optical photograph of the liraglutide microneedles prepared in Example 1;

[0034] Figure 3 This is a comparison chart of blood glucose changes in mice in Example 2;

[0035] Figure 4 The relevant chromatograms are for the gradient dilution configuration at a concentration of 500 μg / ml in Example 3;

[0036] Figure 5 The relevant chromatograms are for the gradient dilution configuration at a concentration of 200 μg / ml in Example 3;

[0037] Figure 6 The relevant chromatograms are for the gradient dilution configuration at a concentration of 100 μg / ml in Example 3;

[0038] Figure 7 The relevant chromatograms are for the gradient dilution configuration at a concentration of 50 μg / ml in Example 3;

[0039] Figure 8 The relevant chromatograms are for the gradient dilution configuration at a concentration of 10 μg / ml in Example 3;

[0040] Figure 9 The relevant chromatograms are for the gradient dilution configuration at a concentration of 5 μg / ml in Example 3;

[0041] Figure 10 The relevant chromatograms are for the detection of liraglutide content in microneedles in Example 3. Detailed Implementation

[0042] The present invention will be further illustrated below with specific embodiments. It should be noted that those skilled in the art can make several modifications and improvements without departing from the principle of the present invention, and these should also be considered to fall within the protection scope of the present invention.

[0043] The contents not described in detail in this specification are common knowledge to those skilled in the art.

[0044] Example 1: Preparation of liraglutide microneedles

[0045] (a) Solution preparation:

[0046] a) Dissolve polyvinylpyrrolidone (PVP) in N-vinylpyrrolidone (NVP) to prepare a solution with a specific gravity and viscosity;

[0047] b) Dissolve a certain amount of photoinitiator in the above solution;

[0048] c) Add liraglutide to the above solution to prepare a homogeneous suspension;

[0049] (II) Microneedle Preparation:

[0050] d) Fill the micropores of the microneedle mold with a uniform suspension under vacuum and remove excess suspension.

[0051] e) Ultraviolet light irradiation causes the liquid NVP in the micropores to polymerize into solid PVP microneedles;

[0052] f) Spread a small amount of NVP containing a photoinitiator on the needle surface of the microneedle mold;

[0053] g) Lay a layer of plastic film flat on the NVP liquid film and press it lightly;

[0054] h) Ultraviolet light irradiation causes NVP in the interlayer to polymerize into PVP, and tightly crosslinks the drug-containing PVP microneedles and plastic film.

[0055] i) Liraglutide microneedles are peeled off from the mold.

[0056] Furthermore, the height of the microneedles is 150-2000 μm, optimized to 900 μm.

[0057] Furthermore, the microneedle is in the shape of a square pyramid, a cone, or a hexagonal pyramid. Preferably, the microneedle is in the shape of a square pyramid with a base side length of 300-550 μm.

[0058] Objectively, the drug loading capacity of microneedles is generally quite small due to the limited volume of the needle. Specifically, in the case of this microneedle, the relationship between NVP and the drug to be carried is also a key factor affecting the drug loading capacity. First, the solvent properties of NVP are approximately between ethanol and acetone, which is insufficient for highly water-soluble drugs. Second, NVP has a specific gravity of 1.04 and low viscosity, causing supersaturated drugs to settle quickly, affecting the uniformity of drug loading and the convergence of drug efficacy. Therefore, adjusting the specific gravity and viscosity of the solvent to ensure uniform drug suspension without sedimentation or floating can increase the drug loading capacity and promote uniformity and convergence of drug efficacy. In this case, the microneedle manufacturing process involves polymerizing liquid NVP into solid PVP. PVP has a specific gravity of 1.144 and good solubility in NVP. The NVP solution with dissolved PVP has a higher specific gravity and viscosity. By adjusting the specific gravity and viscosity to an appropriate range, the appropriate drug can be uniformly suspended within it. The specific gravity, viscosity, and liraglutide suspension of PVP(K30) / NVP solutions with different concentrations are shown in Table 1, and the specific gravity, viscosity, and liraglutide suspension of PVP(K15) / NVP solutions with different concentrations are shown in Table 2. As can be seen from the data in Tables 1 and 2, the addition of PVP can change the specific gravity and viscosity of the solution, significantly slowing down the sedimentation rate of liraglutide, thus meeting the technical requirements for large-scale preparation.

[0059] Table 1. Specific gravity, viscosity, and liraglutide suspension of PVP(K30) / NVP solutions at different concentrations

[0060]

[0061] Table 2. Viscosity, viscosity, and liraglutide suspension of PVP(K15) / NVP solutions at different concentrations

[0062]

[0063] Example 2: Liraglutide microneedle mouse hypoglycemic experiment

[0064] (1) Experimental materials and instruments

[0065] db / db mice (SPF, 15 mice, divided into 3 groups of 5 mice each), 70% ethanol aqueous solution, isoflurane, liraglutide microneedle patch (microneedle patch size 0.4*0.4cm; liraglutide content in microneedle patch 80μg), liraglutide injection (solvent: PBS; concentration: 1mg / ml).

[0066] (2) Group Design

[0067] Five mice were placed in each group, with a total of three groups: a control group, a liraglutide injection group, and a liraglutide microneedle group. The control group was fed normally without any treatment; the liraglutide injection group was injected with liraglutide (80 μl); and the liraglutide microneedle group had a microneedle patch applied to each mouse.

[0068] (3) Experimental steps

[0069] First, the purchased mice were placed in a stable environment for one week (normal feeding), and then their blood glucose levels were measured individually to ensure the model was usable. Mice blood glucose levels should be within the range of 20-35 mmol / L. Next, after testing the mice's blood glucose concentration (recorded as 0h), different groups of mice were treated according to the grouping design. Finally, the blood glucose concentrations of each mouse were recorded at 1, 2, 4, 6, and 12 hours after treatment.

[0070] (4) Experimental Results

[0071] like Figure 3 As shown, compared with the control group, both liraglutide injection and microneedle patch significantly reduced blood glucose concentration in mice, and the blood glucose-lowering effects of liraglutide injection and microneedle patch were similar.

[0072] Example 3: Chemical analysis method for liraglutide microneedles (analysis of liraglutide content in microneedle patches by high performance liquid chromatography)

[0073] (1) Equipment and materials

[0074] High-performance liquid chromatography (Agilent 1260DAD detector), chromatographic column (ZORBAX 300SB-C18), liraglutide, deionized water

[0075] (2) Detection method

[0076] (a) Liquidity selection and settings

[0077] Mobile phase A: Water + 0.1% trifluoroacetic acid; Mobile phase B: Acetonitrile + 0.1% trifluoroacetic acid

[0078]

[0079]

[0080] (b) Parameter settings

[0081] Flow rate: 0.6 ml / min; Column temperature: 20℃; Sample loading volume: 50 μl; Detection wavelength: 214 nm

[0082] (3) Construction of standard curve

[0083] Liraglutide solutions were prepared using a serial dilution technique, resulting in concentrations of 500 μg / ml, 200 μg / ml, 100 μg / ml, 50 μg / ml, 10 μg / ml, and 5 μg / ml. Then, 2 ml of each solution was added to a separate sample vial, and all solutions were analyzed in one batch by HPLC (do not analyze in batches). (See attached...) Figure 6 To be continued Figure 9 We can see that the peak around 18 min is the characteristic peak of liraglutide. The area of ​​the characteristic peak of liraglutide can be obtained by integration, as shown in the table below.

[0084] Liraglutide characteristic peak area

[0085]

[0086] By performing linear fitting on the peak area and liraglutide concentration, it can be determined that when the linear fitting range of liraglutide concentration is 5 μg / ml-500 μg / ml, R 2 =0.9589; Therefore, when the linear fitting range of liraglutide concentration is 5 μg / ml-200 μg / ml, R0 2 = 0.9957. Because R 2 A value greater than 0.98 is required to indicate that the fitted curve has a good linear relationship. The linear fitting range of saliraglutide concentration is 5 μg / ml-200 μg / ml, with corresponding peak areas of 331.6267-14969.4348, and its linear equation is y=75.372x+242.62.

[0087] (4) Detection of liraglutide content in microneedles

[0088] Cut the liraglutide microneedle product into small pieces (without damaging the needle), place them in a 10ml centrifuge tube, add 8ml of deionized water, and soak for 4 hours to allow the liraglutide microneedle product to fully dissolve. Then, take 2ml of the solution to test the concentration of liraglutide; the test results are attached. Figure 10 As shown in the figure, the characteristic peak of liraglutide is located at 17.837 min, with an integral area of ​​12673.4686, ranging from 331.6267 to 14969.4348. Using a linear equation, the concentration of the solution can be calculated to be 164.926612 μg / ml. Therefore, the dosage of liraglutide in WZYY-Y002 can be calculated to be approximately 1.3 mg (164.926612 μg / ml * 8 ml = 1319.412896 μg).

[0089] Example 4: Evaluation of the uniformity of drug loading on microneedle patches

[0090] The drug loading of several liraglutide microneedle tablets was tested and evaluated using the method established in Example 3, and the relatively ideal results are shown in the table below.

[0091] Liraglutide microneedle patch content determination table

[0092]

[0093] The present invention has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present invention. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and embodiments of the present invention without departing from the spirit and scope of the invention, and all such modifications and improvements fall within the scope of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A GLP-1 polypeptide microneedle patch, characterized in that... The main component of the microneedle substrate is polyvinylpyrrolidone (PVP). The PVP has two sources: one is PVP added first to adjust the specific gravity and viscosity of the solution; the other is PVP polymerized from N-vinylpyrrolidone (NVP) after ultraviolet irradiation. The microneedle substrate also contains a photoinitiator and unpolymerized NVP. The microneedle body has a conical structure, and the drug contained therein is a GLP-1 receptor agonist.

2. A method for preparing the GLP-1 polypeptide microneedle patch as described in claim 1 comprises the following steps: (a) Solution preparation: a) Dissolve polyvinylpyrrolidone (PVP) in N-vinylpyrrolidone (NVP) to prepare a solution with a specific gravity and viscosity; b) Dissolve a certain amount of photoinitiator in the above solution; c) Add the GLP-1 receptor agonist to the above solution to prepare a homogeneous suspension of the GLP-1 receptor agonist; (II) Microneedle Preparation: d) Fill the micropores of the microneedle mold with a uniform suspension of GLP-1 receptor agonist under vacuum, and remove excess suspension. e) Ultraviolet light irradiation causes the liquid NVP in the micropores to polymerize into solid PVP microneedles; f) Spread a small amount of NVP containing a photoinitiator on the needle surface of the microneedle mold; g) Lay a layer of plastic film flat on the NVP liquid film and press it lightly; h) Ultraviolet light irradiation causes NVP in the interlayer to polymerize into PVP, and tightly crosslinks the drug-containing PVP microneedles and plastic film. i) Extract GLP-1 peptide microneedles from the mold.

3. The method for preparing a GLP-1 polypeptide microneedle patch according to claim 2, characterized in that, The GLP-1 receptor agonist is one of liraglutide, exenatide, or smegglutide.

4. The method for preparing a GLP-1 polypeptide microneedle patch according to claim 2, characterized in that, The NVP added in step f) contains a photoinitiator at a concentration of 1.5% w / v.

5. The method for preparing a GLP-1 polypeptide microneedle patch according to claim 2, characterized in that, The height of the microneedles is 150-2000 μm.

6. A method for preparing a GLP-1 polypeptide microneedle patch according to claim 2 or 5, characterized in that, The microneedles are cone-shaped or pyramidal.

7. The method for preparing a GLP-1 polypeptide microneedle patch according to claim 6, characterized in that, The microneedles are in the shape of a square pyramid.

Images