CN107714653B - Stable soluble methotrexate granules - Google Patents

Abstract

The invention discloses a stable soluble methotrexate granule which is prepared from the following raw materials in parts by weight: 100-140 parts of methotrexate, 60-80 parts of disodium hydrogen phosphate, 70-80 parts of citric acid, 8.5-100 parts of sodium hydroxide, 30-60 parts of hydroxypropyl cellulose, 160 parts of mannitol 140-140, 40-80 parts of sucralose and 5-10 parts of flavoring agent. The soluble methotrexate granules are prepared by directly taking methotrexate as a raw material for the first time, have good re-solubility and can be quickly dissolved into a clear solution before use, so that the problem of inaccurate dose division of methotrexate tablets is effectively solved; the soluble granules have better stability, the effective period of the medicine is at least more than 2 years under the conventional storage condition, and the bioavailability is high; is particularly suitable for children or old patients with dysphagia, and provides wide prospect for the clinical application of methotrexate.

Description

Stable soluble methotrexate granules

Technical Field

The invention relates to the technical field of pharmaceutical preparations, in particular to stable soluble methotrexate granules.

Background

Methotrexate is an antiproliferative and immunosuppressive agent that has been widely used in the treatment of cancer and immune and inflammatory diseases, such as adult rheumatoid arthritis, juvenile idiopathic arthritis, psoriasis, etc., since the 50 th century. Methotrexate plays a critical role as a classical drug, especially in the clinical treatment of acute lymphocytic leukemia in children and juvenile idiopathic arthritis.

Methotrexate has cytotoxicity, a narrow therapeutic window, and poor or even ineffective curative effect of small dose of methotrexate, while serious toxic and side effects such as bone marrow suppression, digestive tract reaction, renal dysfunction and the like can be caused by large dose of methotrexate. Thus, methotrexate must be administered clinically with strict dose control.

Currently, there are two modes of administration of methotrexate, both injectable and oral, and for pediatric patients, although injectable, it requires intervention techniques and local anesthesia to relieve pain to encourage cooperation; in addition, the child's muscle mass varies, and if proper needle insertion position, needle size and injection angle are not selected, nerve damage or other complications may result when performing intramuscular injection. Oral administration has better safety and patient compliance relative to injection administration. The currently reported oral administration forms of methotrexate mainly include: oral liquid (CN107106485A), orally disintegrating tablet (CN1320887C), tablet, etc., however, the methotrexate oral dosage form approved by the drug regulatory authority at present only has fixed dose tablet, and for the children patients, it is usually necessary to convert the dosage of each administration according to the body weight, children of different ages need to take different dosages due to the difference of body weight, and the fixed dose tablet is often forced to be broken into pieces and divided into doses for administration during use, and there is a safety risk due to inaccurate dose division. For patients with dysphagia (such as the elderly, children, and oral ulcer patients), the administration of conventional tablet by pulverizing has difficulty in dissolving, bitter taste, etc., and poor compliance.

Although the problem of inaccurate dose division of methotrexate can be solved by preparing methotrexate into a solution dosage form, the disadvantages which are difficult to overcome by the solution dosage form include: (1) in a solution state, the stability of methotrexate is poor, and the effective period of the medicine needs to be shortened or more rigorous storage conditions, such as low-temperature storage and the like, need to be adopted; (2) the product has large volume, easy damage, high transportation cost and the like, so that the market application prospect of the methotrexate solution formulation is limited.

The soluble granule is one kind of granule, and different from suspension granule, the soluble granule can be dissolved completely to form clear solution after adding water. The soluble granules can well solve the problems of inaccurate effective component dosage division, poor product stability, difficult storage and transportation and the like. However, because methotrexate is hardly dissolved in water, ethanol, chloroform and diethyl ether, the oral bioavailability is very low, and no report of preparing soluble granules by taking methotrexate as a raw material is found so far.

Disclosure of Invention

In view of the above prior art, it is an object of the present invention to provide stable soluble methotrexate granules which have good reconstitution properties and can be rapidly dissolved into a clear solution before use, so as to avoid the risk of inaccurate dose division; under the conventional storage condition, the compound has better stability and acceptable drug validity; is especially suitable for children or elderly patients with dysphagia.

In order to achieve the purpose, the invention adopts the following technical scheme:

a stable soluble methotrexate granule is prepared from the following raw materials in parts by weight:

100-140 parts of methotrexate, 60-80 parts of disodium hydrogen phosphate, 70-80 parts of citric acid, 8.5-100 parts of sodium hydroxide, 30-60 parts of hydroxypropyl cellulose, 160 parts of mannitol 140-140, 40-80 parts of sucralose and 5-10 parts of flavoring agent.

Preferably, the stable soluble methotrexate granules are prepared from the following raw materials in parts by weight:

130 parts of methotrexate 110-70 parts, 60-70 parts of disodium hydrogen phosphate, 70-80 parts of citric acid, 10-95 parts of sodium hydroxide, 40-50 parts of hydroxypropyl cellulose, 160 parts of mannitol 140-70 parts, 50-70 parts of sucralose and 5-10 parts of flavoring agent.

Further preferably, the stable soluble methotrexate granules are prepared from the following raw materials in parts by weight:

120 parts of methotrexate, 60-70 parts of disodium hydrogen phosphate, 70-80 parts of citric acid, 10-84 parts of sodium hydroxide, 40-50 parts of hydroxypropyl cellulose, 160 parts of mannitol 140, 50-70 parts of sucralose and 5-7 parts of flavoring agent.

More preferably, the stable soluble methotrexate granules are prepared from the following raw materials in parts by weight:

120 parts of methotrexate, 68.64 parts of disodium hydrogen phosphate, 75.24 parts of citric acid, 60 parts of sodium hydroxide, 48 parts of hydroxypropyl cellulose, 150 parts of mannitol, 60 parts of sucralose and 6 parts of flavoring agent.

Preferably, the flavoring agent is a flavoring essence.

The invention also provides a preparation method of the stable soluble methotrexate granules, which comprises the following steps:

(1) adding water into hydroxypropyl cellulose to prepare a water solution with the concentration of 3-5 wt%;

(2) adding methotrexate, disodium hydrogen phosphate, citric acid, sodium hydroxide, sucralose and a flavoring agent into the aqueous solution obtained in the step (1), and stirring until the materials are completely dissolved to obtain a material solution;

(3) placing mannitol in a fluidized bed, adding the material solution, performing fluidized granulation, drying, and sieving to obtain the final product.

Preferably, in the step (1), water is added to the hydroxypropyl cellulose to prepare an aqueous solution with a concentration of 4 wt%.

Preferably, in the step (3), the process conditions of the fluidized granulation are as follows: placing mannitol in fluidized bed, preheating for 5min, top-spraying the loading material solution, spraying at 70 deg.C air inlet, atomizing pressure of 0.2MPa, and peristaltic pump speed of 20r/min until spraying is finished.

Preferably, in the step (3), the drying temperature is 50 ℃ and the drying time is 30 min.

Preferably, in the step (3), the sieving is to sieve the dried particles through a 20-mesh sieve.

Although the fluidized bed granulation is applied more at present, the properties of materials, key process parameters of the granulation and the like can influence the granulation effect. As for material properties, cohesiveness, static electricity and material hydrophobicity are not beneficial to fluidized bed granulation, and methotrexate is difficult to directly perform fluidized bed granulation as a material which is difficult to dissolve in water. In addition, the temperature of air at a spraying inlet, atomizing pressure, spraying speed and the like can influence the granularity and mechanical strength of the particles, and multiple tests show that the particle size of the particles prepared by adopting the fluidized granulation process condition is uniform, the mechanical strength is high, and the particles are not easy to break. If the granulation process conditions are changed, the properties of the prepared granules are reduced to different degrees.

The invention has the beneficial effects that:

the soluble methotrexate granules are prepared by directly taking methotrexate as a raw material for the first time, have good re-solubility and can be quickly dissolved into a clear solution before use, so that the problem of inaccurate dose division of methotrexate tablets is effectively solved; the soluble granules have better stability, the effective period of the medicine is at least more than 2 years under the conventional storage condition, and the bioavailability is high; is particularly suitable for children or old patients with dysphagia, and provides wide prospect for the clinical application of methotrexate.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

As described in the background, the existing methotrexate tablets have the problem of inaccurate dose division due to the narrow therapeutic window of methotrexate; in addition, because methotrexate is hardly soluble in water and ethanol, the solubility problem of methotrexate needs to be overcome when preparing oral solution dosage forms of methotrexate, a large amount of solubilizing components needs to be added, and the inherent disadvantages of the oral solution dosage forms limit the clinical application of methotrexate. Based on the above, the invention provides a stable soluble methotrexate granule, belonging to a new dosage form for clinical application of methotrexate.

For the preparation of the soluble methotrexate granules, the technical difficulties mainly comprise: 1) the solubility of the methotrexate is high on the premise of preparing granules; 2) the re-dissolubility of the granules is improved after the granules are prepared.

For increasing the solubility of a poorly soluble drug, the prior art mostly adopts the addition of a surfactant, a water-soluble polymer, cyclodextrin and the like, or uses a salt form of the drug, but unfortunately, methotrexate salt cannot be used as a raw material drug in some countries and regions (including China). In addition, if methotrexate is prepared by a salt formation process using methotrexate as a raw material, the preparation cost of the formulation increases. The invention unexpectedly discovers that the methotrexate, disodium hydrogen phosphate, citric acid, sodium hydroxide, sucralose and a flavoring agent are blended in a hydroxypropyl cellulose aqueous solution in the test process, so that the methotrexate can be completely dissolved; further research shows that the addition amount of sodium hydroxide is a key factor for regulating whether the methotrexate is completely dissolved, the solubility of the methotrexate in the hydroxypropyl cellulose aqueous solution can be improved when the addition amount of the sodium hydroxide is 8.5-70 wt% of the methotrexate, and the complete dissolution of the methotrexate can be realized when the addition amount of the sodium hydroxide is 50 wt% of the methotrexate.

In addition, the solubility of methotrexate is pH dependent, and thus, disodium hydrogen phosphate, citric acid, sodium hydroxide, which are blended with methotrexate, affect the pH of the solution, and the ratio of the amounts of these substances also affects the solubility of methotrexate. Experiments show that the pH value of the solution is 5.0-7.0 by controlling the adding amount ratio of the disodium hydrogen phosphate, the citric acid and the sodium hydroxide, the dissolving effect of the methotrexate is better, and the dissolving effect of the methotrexate is optimal when the pH value of the solution is 6.25 +/-0.15.

As described above, although there are various methods for increasing the solubility of a poorly soluble drug, this does not mean that a granule prepared by increasing the solubility of a poorly soluble drug by a different method has good re-solubility. Good re-solubility is the key to the preparation of soluble granules. In the test process, the solubility of methotrexate is increased by adding a surfactant, cyclodextrin and a water-soluble polymer respectively, granules are prepared by fluidized granulation, and then the redissolution of the granules prepared by different solubilization methods is examined. Only granules prepared by the process of the present invention can be rapidly dissolved to a clear solution.

In order to make the technical solutions of the present application more clearly understood by those skilled in the art, the technical solutions of the present application will be described in detail below with reference to specific embodiments.

The test materials used in the examples of the present invention are all conventional in the art and commercially available.

The flavoring agent used in the examples and comparative examples of the present invention was orange flavor, which is a commercially available product.

Example 1: preparation of soluble methotrexate granules

1. Raw material prescription:

120 g of methotrexate, 68.64 g of disodium hydrogen phosphate, 75.24 g of citric acid, 60 g of sodium hydroxide, 48 g of hydroxypropyl cellulose, 150 g of mannitol, 60 g of sucralose and 6 g of flavoring agent.

2. The preparation process comprises the following steps:

(1) adding water into hydroxypropyl cellulose in a prescription amount to prepare a 4 wt% aqueous solution for later use;

(2) weighing methotrexate, disodium hydrogen phosphate, citric acid, sodium hydroxide, sucralose and a flavoring agent according to the prescription amount, adding the methotrexate, disodium hydrogen phosphate, citric acid, sodium hydroxide, sucralose and flavoring agent into the aqueous solution obtained in the step (1), and stirring until the methotrexate, the disodium hydrogen phosphate, the citric acid, the sodium hydroxide, the sucralose and the flavoring agent are completely dissolved;

(3) placing mannitol of a prescription amount in a fluidized bed for preheating for 5min, top spraying, adding the solution stirred in the step (2) until the solution is completely dissolved, carrying out fluidized granulation until the air temperature at a spraying inlet is 70 ℃, the atomization pressure is 0.2MPa, the peristaltic pump speed is 20r/min until the liquid spraying is finished, then drying for 30min at 50 ℃, and sieving the dried granules with a 20-mesh sieve to obtain the soluble methotrexate granules.

Example 2: preparation of soluble methotrexate granules

1. Raw material prescription:

100 g of methotrexate, 80 g of disodium hydrogen phosphate, 70 g of citric acid, 100 g of sodium hydroxide, 30 g of hydroxypropyl cellulose, 160 g of mannitol, 40 g of sucralose and 10g of flavoring agent.

The preparation process is the same as in example 1.

Example 3: preparation of soluble methotrexate granules

1. Raw material prescription:

140 g of methotrexate, 60 g of disodium hydrogen phosphate, 80 g of citric acid, 8.5 g of sodium hydroxide, 60 g of hydroxypropyl cellulose, 140 g of mannitol, 80 g of sucralose and 5 g of flavoring agent.

The preparation process is the same as in example 1.

Example 4: preparation of soluble methotrexate granules

1. Raw material prescription:

110 g of methotrexate, 70 g of disodium hydrogen phosphate, 70 g of citric acid, 95 g of sodium hydroxide, 40 g of hydroxypropyl cellulose, 160 g of mannitol, 50 g of sucralose and 10g of flavoring agent.

The preparation process is the same as in example 1.

Example 5: preparation of soluble methotrexate granules

1. Raw material prescription:

130 g of methotrexate, 60 g of disodium hydrogen phosphate, 80 g of citric acid, 10g of sodium hydroxide, 50 g of hydroxypropyl cellulose, 140 g of mannitol, 70 g of sucralose and 5 g of flavoring agent.

The preparation process is the same as in example 1.

Comparative example 1:

1. raw material prescription:

120 g of methotrexate, 68.64 g of disodium hydrogen phosphate, 75.24 g of citric acid, 9.6 g of sodium hydroxide, 48 g of hydroxypropyl cellulose, 150 g of mannitol, 60 g of sucralose and 6 g of flavoring agent.

The preparation method is the same as example 1.

Comparative example 2:

1. raw material prescription:

120 g of methotrexate, 68.64 g of disodium hydrogen phosphate, 75.24 g of citric acid, 90 g of sodium hydroxide, 48 g of hydroxypropyl cellulose, 150 g of mannitol, 60 g of sucralose and 6 g of flavoring agent.

The preparation method is the same as example 1.

Comparative example 3:

1. raw material prescription:

120 g of methotrexate, 68.64 g of disodium hydrogen phosphate, 75.24 g of citric acid, 48 g of hydroxypropyl cellulose, 150 g of mannitol, 60 g of sucralose and 6 g of flavoring agent.

2. The preparation process comprises the following steps:

(1) adding water into hydroxypropyl cellulose in a prescription amount to prepare a 4 wt% aqueous solution for later use;

(2) weighing methotrexate, disodium hydrogen phosphate, citric acid, sucralose and a flavoring agent according to the prescription amount, adding the methotrexate, disodium hydrogen phosphate, citric acid, sucralose and flavoring agent into the aqueous solution obtained in the step (1), and stirring for dissolving;

(3) and (3) putting the mannitol with the prescription amount into a fluidized bed, adding the solution dissolved in the step (2) by stirring, performing fluidized granulation, drying, and sieving to prepare the granules.

Wherein, in the step (2), methotrexate is difficult to dissolve when the methotrexate is dissolved by stirring, and the obtained solution is suspension.

Test example 1: quality inspection of granules

1. And (3) redissolution investigation:

the granules prepared in each example and comparative example were reconstituted by adding an equal amount of deionized water and the time required to completely dissolve to form a clear solution was recorded and the results are shown in table 1.

Table 1: test results of resolubility

	Time required for reconstitution(s)
		Example 1	4.2
Example 2	4.8
		Example 3	7.2
Example 4	5.4
		Example 5	6.8
Comparative example 1	18.2
		Comparative example 2	24.5
Comparative example 3	No clear solution can be formed

2. And (3) stability investigation:

according to the guideline of stability test of XIXc raw material medicine and pharmaceutical preparation in appendix XIXc of the second part of the version 2015 of Chinese pharmacopoeia, the soluble granules prepared in the embodiment 1 of the invention are subjected to accelerated stability test and long-term stability test investigation.

Conditions for accelerated stability testing: the test articles of 3 lots were packaged on the market, and left for 6 months at 40 ℃ and 75% relative humidity, and sampled 1 time each at 0 th, 1 th, 3 th and 6 th months during the test period, and examined according to the stability items. The results show that: the soluble granules have good stability under high-temperature and high-humidity conditions, and all indexes examined have no obvious change, so that the result meets the specification. The results of the accelerated test examination of "related substances" are shown in Table 2.

Table 2: test results of accelerated stability test on substances

Examination item	Related substance (%)
		0 month	0.243
1 month	0.272
		3 month	0.277
6 month	0.301

Long-term stability test conditions: the test samples of 3 lots were packaged on the market, left for 24 months at 25 ℃ and 60% relative humidity, and sampled 1 time each at 0, 1, 3, 6, 12, 18, and 24 months during the test period, and examined according to the stability items. The results show that: the soluble granules have good stability under the condition of normal-temperature storage, and all indexes examined have no obvious change, and the result conforms to the specification. The results of the accelerated test examination of "related substances" are shown in Table 3.

Table 3: long term stability test on the results of examination of the relevant substances

Examination item	Related substance (%)
		0 month	0.243
1 month	0.249
		3 month	0.254
6 month	0.251
		12 month	0.255
18 months	0.252
		24 months	0.254

4. Stability study of the methotrexate granule preparation solution:

the methotrexate granules prepared in example 1 of the present invention were formulated into a solution with a concentration of 2mg/ml using deionized water, and the stability of the solution formulated with the methotrexate granules was examined at room temperature under dark conditions. The results are shown in Table 4.

Table 4: stability test results of methotrexate granule preparation solution

As can be seen from Table 5, the aqueous solution prepared from the methotrexate granules of the present invention was stable for at least 8 weeks.

Test example 2: bioavailability study

1. Blood concentration measurement

1.1 test methods

Male SD rats weighing 200 + -10 g were selected and randomly divided into 4 groups, and each group was re-gavaged with methotrexate granule solution prepared in example 1 and granule suspension prepared in comparative examples 1-3 according to animals at an administration amount of 50 mg/kg^-1。

Rats were fasted for 12h before administration and 0.5ml of blank plasma was collected from the orbit using a glass capillary before administration. Each group was orally administered with 0.5ml of blood collected from the orbit at 5, 15, 30, 60, 90, 120, 180, 240min after administration. Immediately thereafter, the rats were sacrificed, decapitated, blood samples were collected, and plasma samples were all cryopreserved at-20 ℃ for one week and 3 rats were repeated at each time point.

1.2 test results

The results of the measurement of the blood methotrexate concentration are shown in Table 5.

Table 5: measurement of methotrexate concentration in blood

t(min)	Example 1(ng/ml)	COMPARATIVE EXAMPLE 1(ng/ml)	COMPARATIVE EXAMPLE 2(ng/ml)	COMPARATIVE EXAMPLE 3(ng/ml)
					5	274.23±54.52	143.27±56.68	101.27±55.55	48.95±21.25
15	846.70±76.55	394.71±80.12	412.08±78.48	96.36±46.69
					30	1412.64±72.48	962.51±72.84	825.74±72.65	318.66±74.13
60	3246.69±148.29	1463.82±152.39	1885.69±145.68	502.14±26.53
					90	2043.28±116.95	2108.56±140.73	1264.35±130.58	264.18±42.65
120	612.14±125.73	550.69±93.40	402.68±113.85	168.58±63.40
					180	136.58±80.25	121.62±80.20	129.45±93.40	91.54±42.32
240	60.18±21.36	47.68±31.35	43.26±25.41	32.45±18.62

As can be seen from table 5, the granules prepared in example 1 of the present invention can achieve higher blood levels in a short time, relative to comparative examples 1 to 3; moreover, the blood concentration is maintained for a longer time.

2. Relative bioavailability assay

The bioavailability is a comprehensive parameter for measuring the absorption speed and degree of the drug and is an important index for evaluating the curative effect of the drug, the test compares the area under the plasma traditional Chinese medicine-hour curve with the granules prepared in example 1 and comparative examples 1-3 by taking the methotrexate tablet as a reference preparation, and the relative bioavailability is calculated according to a formula, and the result is shown in table 6.

Relative bioavailability:

t- - -test agent; r-reference preparation.

Table 6: results of bioavailability test

Group of	Relative bioavailability (%)
		Example 1	121.4
Comparative example 1	94.2
		Comparative example 2	96.5
Comparative example 3	76.8

As can be seen from table 6, the bioavailability of the soluble granules prepared in example 1 was significantly improved and the drugs were safer and more effective than those of comparative examples 1 to 3.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (2)

1. The stable soluble methotrexate granules are characterized by being prepared from the following raw materials in parts by weight:

120 parts of methotrexate, 68.64 parts of disodium hydrogen phosphate, 75.24 parts of citric acid, 60 parts of sodium hydroxide, 48 parts of hydroxypropyl cellulose, 150 parts of mannitol, 60 parts of sucralose and 6 parts of flavoring agent;

the soluble methotrexate granules are prepared by the following method:

(1) adding water into hydroxypropyl cellulose to prepare a 4 wt% aqueous solution;

(2) adding methotrexate, disodium hydrogen phosphate, citric acid, sodium hydroxide, sucralose and a flavoring agent into the aqueous solution obtained in the step (1), and stirring until the materials are completely dissolved to obtain a material solution;

(3) placing mannitol of a prescription amount in a fluidized bed for preheating for 5min, top spraying, adding the solution stirred in the step (2) until the solution is completely dissolved, carrying out fluidized granulation until the air temperature at a spraying inlet is 70 ℃, the atomization pressure is 0.2MPa, the peristaltic pump speed is 20r/min until the liquid spraying is finished, then drying for 30min at 50 ℃, and sieving the dried granules with a 20-mesh sieve to obtain the soluble methotrexate granules.

2. The soluble methotrexate granules of claim 1, wherein the flavoring agent is a flavorant.