Use of alprazolam gel microparticles in preparing a drug for treating status epilepticus

Abstract

This invention relates to the field of epilepsy, specifically to the use of alprazolam gel microparticles in the preparation of a medicament for treating status epilepticus. The invention provides the use of alprazolam gel microparticles in the preparation of a medicament for treating and / or preventing seizures in subjects, characterized in that the alprazolam gel microparticles are prepared through the following steps: S101 adding an alprazolam solution dropwise to a first solution to form an inner phase solution; S102 forming pre-crosslinked droplets that have undergone preliminary solidification; S103 forming solidified microparticles; S104 obtaining the alprazolam gel microparticles. The alprazolam gel microparticles provided by this invention have a blood-brain barrier permeability 1.5-2 times that of existing technologies, a rapid onset of action, and possess both rapid and sustained release properties, making them suitable for effective and timely treatment of patients experiencing seizures.

Description

Technical Field

[0001] The invention relates to the field of epilepsy, and in particular to use of alprazolam gel particles in preparing a medicine for treating status epilepticus. Background Art

[0002] Epilepsy is one of the most common chronic neurological diseases, with more than 70 million patients worldwide. Epileptic seizures are caused by sudden abnormal, self-sustaining discharges in brain networks, usually lasting less than a few minutes. Symptoms of epileptic seizures may affect any part of the body, and are usually manifested as sudden recurrence of sensory disturbances, loss of consciousness, or convulsions. Status epilepticus (also known as status epilepticus, SE) is a severe state of epileptic seizures, which refers to a critical neurological condition in which consciousness is not fully restored during continuous epileptic seizures and recurs frequently, or seizures last for more than 30 minutes and do not stop on their own. From the perspective of clinical practice, a generalized convulsive seizure lasting more than 5 minutes, or a non-convulsive or partial seizure lasting more than 15 minutes, or a person whose consciousness is not fully restored during the interval between two seizures within 5 to 30 minutes, can be considered as early SE, because most seizures at this stage cannot be relieved on their own and require emergency treatment to prevent them from evolving into full status epilepticus. Current emergency treatment usually focuses on intravenous / muscular infusion of higher doses of anti-epileptic drugs (even anesthetic drugs).

[0003] If prolonged epileptic seizures are not treated in time, they can lead to irreversible brain damage due to high fever, circulatory failure or neuronal excitotoxic damage, with high disability and mortality rates. Because epilepsy often occurs suddenly and epilepsy itself lacks predictability, approximately 120,000 people die from epilepsy worldwide each year. In other words, although clinical emergency treatment can specifically treat status epilepticus, from a practical point of view, emergency treatment is usually difficult to immediately treat patients (such as during early SE). Benzodiazepines Drugs of this type (such as alprazolam) have sedative, tranquilizing and muscle relaxant properties and can be used to treat status epilepticus. Chinese patent application CN110267662A discloses oral administration of alprazolam in the form of condensed aerosol. Although it can take effect relatively quickly, it is easily restricted by the patient's lips and teeth being tightly closed during an epileptic seizure, which is not conducive to the patient's self-administration or the assistance of others in administering the drug. Chinese patent application CN1303674A discloses an alprazolam nasal spray, which is composed of the main drug alprazolam, a solvent and other pharmaceutical excipients, and according to the characteristics of nasal administration and the physical and chemical properties of the drug, solution-type, suspension-type, gel-type and emulsion-type nasal inhalation preparations are prepared. Due to the benzodiazepine The drug is difficult to dissolve in water. When preparing alprazolam nasal spray, a large amount of cosolvent or even organic solvent needs to be added. The participation of cosolvent or organic solvent often makes the prepared nasal spray more irritating. In addition, the nasal spray can easily cause excessive local drug concentration, which has a negative impact on the safety of patients' medication. U.S. Patent No. 8,895,546 discloses a benzodiazepine for nasal administration. The pharmaceutical composition of this type of drug still requires a large amount of organic solvents, which has a negative impact on the safety of patients' medication and may take 15 to 40 minutes to take effect. Summary of the invention

[0004] The present invention provides a use of alprazolam gel microparticles in preparing a drug for treating and / or preventing epileptic seizures in a subject, wherein the alprazolam gel microparticles are prepared by the following steps:

[0005] S101: adding an alprazolam solution dropwise to a first solution to form an inner phase solution; wherein the alprazolam solution comprises alprazolam, methanol and dichloromethane; the first solution is an albumin-sodium alginate aqueous solution; and the inner phase solution is an albumin-sodium alginate aqueous solution loaded with alprazolam;

[0006] S102, using the inner phase solution formed in step S101 as a dispersed phase and the second solution as a continuous phase, performing a pre-crosslinking reaction in a microfluidic chip to form preliminarily solidified pre-crosslinked droplets;

[0007] S103: collecting the pre-crosslinked droplets formed in step S102 in a third solution to perform a crosslinking reaction to form solidified particles;

[0008] S104: washing and freeze-drying the solidified microparticles formed in step S103 to obtain the alprazolam gel microparticles.

[0009] In some embodiments, the mass ratio of the methanol to the dichloromethane in the alprazolam solution is 4:1.

[0010] In some embodiments, the concentration of alprazolam in the alprazolam solution comprises 10-15 wt %.

[0011] In some embodiments, the second solution is a calcium chloride solution, wherein the mass fraction of the calcium chloride is 0.2-1 wt %.

[0012] In some embodiments, the third solution is a calcium chloride solution, wherein the mass fraction of the calcium chloride is 2-4 wt %.

[0013] In some embodiments, the concentration of sodium alginate in the first solution is 0.9-3.0 wt %, and the concentration ratio of the albumin to the sodium alginate is 1:(0.7-1.2).

[0014] In some embodiments, the inner diameter of the channel of the microfluidic chip comprises 70 μm.

[0015] In some embodiments, the flow rate ratio of the continuous phase to the dispersed phase is 1:(5-20).

[0016] In some embodiments, the flow rate of the dispersed phase comprises 2-100 μL / min.

[0017] In some embodiments, the flow rate of the continuous phase comprises 10-500 μL / min.

[0018] In some embodiments, the temperature of the microfluidic chip in step S101 is controlled to be 40-45°C.

[0019] In some embodiments, the alprazolam gel microparticles have both rapid release and sustained release properties.

[0020] In some embodiments, the alprazolam gel particles contain at least alprazolam, albumin and sodium alginate, wherein the mass ratio of the alprazolam to the albumin is 1:(1.3-1.5), and the mass ratio of the alprazolam to the sodium alginate is 1:(0.6-1.8).

[0021] In some embodiments, the mass ratio of the alprazolam to the albumin is 1:1.3.

[0022] In some embodiments, the mass ratio of the alprazolam to the sodium alginate is 1:0.94.

[0023] The alprazolam gel microparticles provided by the present invention have both rapid release performance and sustained release performance. It should be emphasized that experiments have shown that the blood-brain barrier permeability (brain penetration rate) of the alprazolam gel microparticles provided by the present invention is about 70%. Compared with the alprazolam nasal sprays (including solution type, suspension type, gel type and emulsion type) in the prior art, the blood-brain barrier permeability of the alprazolam nasal inhalation preparation provided by the present invention is significantly improved, the bioavailability is high, and it can take effect quickly (for example, within 2 minutes).

[0024] The alprazolam gel particles provided by the present invention are loaded with an appropriate amount of alprazolam on their surfaces, which can achieve rapid release of alprazolam and take effect in the early stage of administration, and can stably combine with the nasal cavity after administration, thereby continuously releasing the alprazolam inside the alprazolam gel particles, thereby achieving sustained release of alprazolam in the middle and late stages of administration.

[0025] In addition, the present invention achieves the above-mentioned effect by controlling alprazolam, albumin and sodium alginate in a specific ratio. For example, when the content of alprazolam is high, although the drug loading is increased, the particle size of the alprazolam gel microparticles is not controlled, and the local concentration of alprazolam is easily increased, and the blood-brain barrier permeability is reduced, which is not conducive to maintaining the dual performance of rapid release and sustained release. When the content of alprazolam is high, not only the drug loading becomes low, but also the particle size of the alprazolam gel microparticles is not controlled, and the blood-brain barrier permeability is reduced, which is not conducive to maintaining the dual performance of rapid release and sustained release. When the content of alprazolam is high, not only the drug loading becomes low, but also the particle size of the alprazolam gel microparticles is not controlled, and the blood-brain barrier permeability is reduced, which is not conducive to maintaining the dual performance of rapid release and sustained release.

[0026] In some embodiments, the particle size of the alprazolam gel microparticles includes 10-50 μm. Based on the microfluidic emulsification technology of the present invention (for example, regulating the inner diameter of the channel of the microfluidic chip, the flow rate ratio of the continuous phase and the dispersed phase), the present invention can prepare alprazolam gel microparticles with uniform and controllable particle size (for example, the particle size can be controlled at 10-50 μm). The above particle size range not only reduces the risk of gel microparticles with too small particle size being inhaled into the lungs, but also ensures the effective drug loading of the gel microparticles and the precise release of the drug, thereby ensuring the blood-brain barrier permeability and medication safety of the alprazolam nasal inhalation preparation.

[0027] In some embodiments, the seizure comprises a focal seizure or a generalized seizure.

[0028] In some embodiments, the use includes providing the subject with protection from epileptic seizures, reducing or lessening the intensity of epileptic seizures, reducing or ameliorating the frequency of epileptic seizures, interrupting epileptic seizures, and / or preventing the occurrence or recurrence of epileptic seizures.

[0029] In some embodiments, the drug is prepared in the form of dosage units, wherein the drug is prepared as an independent dosage form containing 0.5 mg to 4 mg of alprazolam for a single use, and one independent dosage form is prepared as one dosage unit.

[0030] In some embodiments, the subject is a patient with refractory epilepsy.

[0031] In some embodiments, the subject is in a state of epilepsy.

[0032] In some embodiments, the subject is in an early stage of an epileptic seizure state.

[0033] In some embodiments, the epileptic seizures include myoclonic seizures, clonic seizures, tonic seizures, tonic-clonic seizures, and atonic seizures.

[0034] In some embodiments, the drug is a nasal inhalation formulation.

[0035] Compared with the prior art, the beneficial effects of the present invention include at least the following aspects:

[0036] Although nasal inhalation preparations theoretically have advantages such as rapid onset of drug action, the present invention has proved through experiments that existing alprazolam nasal inhalation preparations have problems such as high local alprazolam concentration and low blood-brain barrier permeability during administration, which not only makes it difficult to effectively treat patients in status epilepticus, but also introduces additional stimulation to patients, causing serious negative impact on the safety of patients' medication, and therefore is difficult to use in practice.

[0037] Compared with the prior art, the alprazolam nasal inhalation preparation provided by the present invention can achieve a blood-brain barrier permeability of 1.5-2 times that of the alprazolam nasal inhalation preparation of the prior art, has a fast onset of action (e.g., within 2 minutes), and has both rapid release and sustained release properties, and is suitable for effective and timely treatment of patients in status epilepticus (especially in the early stage of status epilepticus). The alprazolam nasal inhalation preparation provided by the present invention can be stably combined with the nasal cavity and has low irritation, thereby being able to better inhibit (or prevent) potential epileptic seizures in patients, and has high practical application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The graph is a graph showing the in vitro release rate of the alprazolam nasal spray prepared in Example 1 of the present invention and Comparative Examples 1-4 as a function of release time;

[0039] Figure 2 The bar graph is a test data bar graph of the blood-brain barrier permeability of the alprazolam nasal spray prepared in Example 1 of the present invention and Comparative Examples 1-3. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0041] Herein "and / or" includes any and all combinations of one or more of the associated listed items.

[0042] Herein, "plurality" means two or more than two, ie, it includes two, three, four, five, etc.

[0043] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0044] As used in this specification, the term "about" typically means + / - 5% of the stated value, more typically + / - 4% of the stated value, more typically + / - 3% of the stated value, more typically + / - 2% of the stated value, even more typically + / - 1% of the stated value, and even more typically + / - 0.5% of the stated value.

[0045] In this specification, some embodiments may be disclosed in a format of being in a range. It should be understood that this description of "being in a range" is only for convenience and brevity, and should not be interpreted as a rigid limitation on the disclosed range. Therefore, the description of the range should be considered to have specifically disclosed all possible sub-ranges and independent numerical values ​​within this range. For example, the description of the range 1-6 should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as individual numbers within this range, such as 1, 2, 3, 4, 5 and 6. Regardless of the breadth of the range, the above rules apply.

[0046] In order to make those skilled in the art better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with specific embodiments and drawings. Unless otherwise specified, the raw materials, reagents or devices used in the following examples can be obtained from conventional commercial channels or can be obtained by existing known methods.

[0047] Example 1-5: Preparation of gel microparticle-type alprazolam nasal inhalation preparation.

[0048] The prescription is shown in Table 1 below.

[0049] Table 1. Prescriptions for the preparation of alprazolam nasal inhalation preparations in various embodiments

[0050]

[0051]

[0052] Based on Table 1, the preparation was carried out as follows:

[0053] (1) dissolving alprazolam in a methanol-dichloromethane mixed solvent to obtain solution a;

[0054] (2) slowly adding solution a dropwise into the albumin-sodium alginate aqueous solution, heating to 40° C., and cooling to obtain the albumin-sodium alginate aqueous solution loaded with alprazolam, i.e., the inner phase b;

[0055] (3) using a microfluidic method, with the internal phase b as the dispersed phase and the aqueous solution containing calcium chloride as the continuous phase, a pre-crosslinking reaction occurs in the microfluidic chip, the continuous phase shears and preliminarily solidifies the internal phase b, and a preliminarily solidified pre-crosslinked droplet is obtained;

[0056] (4) collecting the pre-crosslinked liquid in a collection phase for crosslinking reaction, and further curing to obtain cured particles;

[0057] (5) washing the solidified particles with pure water by suction filtration;

[0058] (6) vacuum freeze-drying the washed particles to obtain alprazolam gel particles;

[0059] (7) taking the prepared alprazolam gel microparticles to determine the content, filling, sealing, and installing a particle spray pump to obtain a gel microparticle-type alprazolam nasal spray.

[0060] After testing, the particle size and drug loading data of the alprazolam gel microparticles prepared in Examples 1 to 5 are shown in Table 2 below.

[0061] Table 2. Technical parameters of microfluidics and particle size and drug loading data of alprazolam gel microparticles of Examples 1-5

[0062]

[0063] As can be seen from Table 2 above, when the mass ratio of alprazolam to albumin is within the range of 1:(1.3-1.5), alprazolam gel microparticles with a particle size of 10-50 μm can be prepared more stably, and the drug loading is 25.41%-28.9%, which is suitable for preparing alprazolam nasal inhalation preparations. When the mass ratio of alprazolam to albumin is greater than 1:1.5, not only the drug loading of alprazolam gel microparticles is reduced, but also the particle size of the obtained gel microparticles is less than 10 μm, which is prone to the risk of inhalation into the lungs and the release performance is unstable. When the mass ratio of alprazolam to albumin is less than 1:1.3, the particle size of the obtained alprazolam gel microparticles is greater than 50 μm, and compared with the 10-50 μm gel microparticles, the release performance is unstable, which affects the therapeutic effect of SE.

[0064] Comparative Example 1: Preparation of solution-type alprazolam nasal spray

[0065] See the nasal spray prepared in Example 1 disclosed in patent CN1303674A.

[0066] Comparative Example 2: Preparation of gel-type alprazolam nasal spray

[0067] See the nasal spray prepared in Example 5 disclosed in patent CN1303674A.

[0068] Comparative Example 3: Preparation of suspension type alprazolam nasal spray

[0069] See the nasal spray prepared in Example 6 disclosed in patent CN1303674A.

[0070] Comparative Example 4: Preparation of emulsion type alprazolam nasal spray

[0071] See the nasal spray prepared in Example 12 disclosed in patent CN1303674A.

[0072] The nasal sprays of Example 1 and Comparative Examples 1-4 were tested for in vitro release (IVTR) respectively. The experimental method was based on the "Expert Consensus on Technical Specifications for In Vitro Release Tests of Semisolid Preparations for Skin and Mucous Membranes" (Chinese Modern Applied Pharmacy, Vol. 39, No. 20, October 2022), and a three-dimensional diffusion cell model was used. The test results are shown in Figure 1 .

[0073] from Figure 1 It can be seen that the nasal sprays of comparative examples 1-4 can be released quickly at the initial stage of administration (e.g., within 1 hour). On the one hand, this will result in an excessively high local concentration of alprazolam; on the other hand, in practical applications, this will result in the release of alprazolam being terminated at the initial stage of administration. When faced with patients with status epilepticus that is difficult to control, the nasal sprays of comparative examples 1-4 are often difficult to control continued epileptic seizures. In other words, the nasal sprays of comparative examples 1-4 may need to be administered repeatedly. However, since alprazolam is a prescription drug, it is difficult for epileptic patients to carry multiple doses of nasal sprays such as those of comparative examples 1-4, which will increase the risk of status epilepticus being difficult to control and limit the time for patients to be sent to the doctor for treatment. The alprazolam nasal inhalation preparation of Example 1 of the present invention can be released quickly at the initial stage of administration, achieving the purpose of rapid onset of action while also having a certain effect of controlling local concentration, reducing irritation to patients (especially to the nasal cavity).

[0074] Combination Figure 2It can be seen from the blood-brain barrier permeability that the 1-hour blood-brain barrier permeability of the alprazolam nasal inhalation preparation of Example 1 of the present invention is significantly higher than that of Comparative Examples 1-3, which indicates that the alprazolam nasal inhalation preparation provided by the present invention significantly improves the blood-brain barrier permeability of the alprazolam drug, and can achieve efficient and rapid release within 1 hour. Compared with the nasal spray of Comparative Examples 1-3, in the middle and late stages of administration, the alprazolam nasal inhalation preparation of Example 1 of the present invention has a better sustained-release effect, and can achieve continuous slow release within 24 hours. The effect of controlling status epilepticus is sufficient to persist until the epileptic patient is sent to the doctor for treatment, without the need for repeated administration, and is particularly suitable for situations where the patient does not have sufficient time to be sent to the doctor for treatment. In addition, the alprazolam nasal inhalation preparation provided by the present invention can also avoid the stimulation caused by repeated administration of Comparative Examples 1-4, thereby reducing the clearance effect of cilia on alprazolam.

[0075] The method for detecting the blood-brain barrier permeability is as follows: rats are given 10 μg of the nasal spray of Example 1 and Comparative Examples 1-3, respectively, and plasma and brain tissue samples are collected one hour later. After the samples are pre-treated, the supernatant is extracted, and the concentration of alprazolam is detected using a liquid chromatography-mass spectrometry method, and the ratio of the brain tissue concentration to the plasma concentration is the blood-brain barrier permeability. The chromatographic conditions of the detection method are: chromatographic column ACQUITY UPLC HSS T3 (100*2.1mm, 1.8μm), temperature setting 40°C, mobile phase 0.1% formic acid aqueous solution (aqueous phase) and 0.1% formic acid acetonitrile (organic phase), flow rate 0.3ml / min, run for 7 minutes. The mass spectrometry conditions are MRM=309.2 / 281.2.

[0076] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which all fall within the protection of the present invention.

Claims

1. Use of alprazolam gel microparticles in the preparation of a drug for treating and / or preventing epileptic seizures in a subject, characterized in that: The alprazolam gel particles are prepared by the following steps: S101 adding an alprazolam solution dropwise to the first solution to form an inner phase solution; wherein the alprazolam solution is a solution of alprazolam, methanol and dichloromethane; the first solution is an albumin-sodium alginate aqueous solution; and the inner phase solution is an albumin-sodium alginate aqueous solution loaded with alprazolam; S102: using the inner phase solution formed in step S101 as a dispersed phase and the second solution as a continuous phase, performing a pre-crosslinking reaction in a microfluidic chip to form preliminarily solidified pre-crosslinked droplets; S103 collecting the pre-crosslinked droplets formed in step S102 in a third solution to perform a crosslinking reaction to form solidified particles; S104 washing the solidified particles formed in step 103 and freeze-drying them to obtain the alprazolam gel particles; the alprazolam gel particles at least contain alprazolam, albumin and sodium alginate, the mass ratio of alprazolam to albumin is 1:1.3-1.5, and the mass ratio of alprazolam to sodium alginate is 1:0.6-1.8; Wherein, the second solution is a calcium chloride solution, wherein the mass fraction of the calcium chloride is 0.2-1wt%; and the third solution is a calcium chloride solution, wherein the mass fraction of the calcium chloride is 2-4wt%.

2. The use according to claim 1, characterized in that The particle size of the alprazolam gel microparticles is 10-50 μm.

3. The use according to claim 1, characterized in that The epileptic seizure is a focal epileptic seizure or a generalized epileptic seizure.

4. The use according to claim 1, characterized in that The drug is prepared in the form of dosage units, with 0.5 mg to 4 mg of alprazolam being prepared as an independent dosage form for single use, and 1 independent dosage form being prepared as one dosage unit.

5. The use according to claim 1, characterized in that: The subject is in a state of epileptic seizure.

6. The use according to claim 1, characterized in that: The subject is in an early stage of an epileptic seizure.

7. The use according to claim 1, characterized in that The medicine is a nasal inhalation preparation.

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