JPH0129481B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an iron complex compound useful for the treatment of iron deficiency anemia, and more particularly to a method for producing a parenterally administrable dextrin/hydroxycarboxylic acid/ferric polynuclear complex. Treatment for iron deficiency anemia mainly relies on oral administration of iron, but in cases where large doses of iron are required, or when orally administered iron is not absorbed properly, or because of side effects, etc. Parenteral administration of iron is used instead of oral administration in cases where the patient cannot tolerate oral administration of iron, or in cases where iron loss due to chronic persistent bleeding is higher than iron absorption and loss of stored iron is observed. When iron is administered orally, the rate of absorption from the intestinal tract depends on the free iron concentration, so the therapeutic effect is higher when iron is released.As a result, ferrous iron, which can exist as free iron at high concentrations, is often used. There is. On the other hand, in the case of parenteral iron preparations, free iron is known to put the administered body in an extremely dangerous state depending on the amount, so efforts are being made to manufacture iron preparations with a low proportion of free iron. In addition, parenteral iron preparations have a moderately high molecular weight, are excreted little in the urine, have a high iron concentration, are easy to obtain an injection solution that is isotonic with body fluids, and are near neutral. In order to maintain the safety and stability of the product, it is required to be stable in solution and to have high storage stability in the solution state, and has fundamentally different issues than oral iron preparations. Extremely sophisticated manufacturing technology is required. Several techniques have disclosed that complexes consisting of ferric salts, mono- or oligosaccharides, and hydroxycarboxylic acids are effective in treating iron deficiency anemia. For example, Special Publication No. 40-7296,
-17782 contains ferric salts, hexitol and
A method is presented for reacting tribasic hydroxycarboxylic acids in the presence of dispersion stabilizers to obtain iron formulations. However, in this method, 15~
A formulation with a relatively low iron content of 16% by weight was obtained and was also acutely toxic when administered intravenously to mice.
It has the disadvantage of exhibiting high toxicity with an LD ₅₀ of 35 mg/Kg. In addition, Japanese Patent Publication No. 46-3196 discloses 1 mole of ferric hydroxide, about 1.5 mole of sorbitol, about 0.4 mole of gluconic acid, and 0.5 mole of dextrin, dextran, hydrogenated dextrin, or hydrogenated dextran with an average molecular weight of 500 to 1200 ( (as glucose) to obtain an iron preparation. Even with this method, the iron content of the iron preparation obtained is only 21-26% by weight, and when administered to humans, 10% of the administered iron amount is excreted in the urine, and the LD ₅₀ in mice is also low. It has drawbacks that need to be improved, such as relatively high toxicity of 380 mg/Kg when injected internally. In addition to the drawbacks mentioned above, these saccharide/hydroxycarboxylic acid/ferric iron complexes have relatively small molecular weights, so they may damage blood cells, blood vessels, muscles, etc., and the complex solution is far removed from blood and body fluids. It has disadvantages as a parenteral iron agent, such as being stable only at high pH. In addition, in the dextran/ferric iron complex conventionally used as a parenteral iron preparation, dextran itself is expensive, decomposes extremely slowly in the body, and has a tendency to accumulate. When iron complexes are administered parenterally, their uptake into the reticuloendothelial system in vivo is poor, and accumulation in the blood is observed.
It has various drawbacks as a parenteral iron preparation, as it acts as an antigen and produces antibodies, and is also reported to be carcinogenic. On the other hand, in the dextrin/ferric iron complex, the composition dextrin has degrading enzymes in the living body, so it does not accumulate like dextran does, and does not produce harmful immune antibodies.
Furthermore, the dextrin/ferric iron complex, which has a large molecular weight, has many advantages such as not being filtered by the kidneys and being excreted in the urine. However, dextrins have reducing groups and tend to reduce ferric iron to ferrous iron, producing free ferrous ions. Further, the dextrin/ferric iron complex has drawbacks such as insufficient long-term storage stability and insufficient thermal stability in an aqueous solution state. Therefore, the present inventors attempted to improve the stability of these preparations by using high-molecular-weight dextrins, but the desired effects could not be obtained and only products with low iron content and poor therapeutic effects were obtained. On the other hand, attempts were made to produce a dextrin/ferric iron complex that would enhance the therapeutic effect by increasing the iron content, reduce the influence of the reducing group of dextrin, and be less likely to generate free ferrous ions, but such a complex However, the water holding capacity decreased and only unstable products could be obtained. The present inventors used dextrins with appropriate molecular weights, citric acid, gluconic acid, tartaric acid, malic acid,
Coordinating at least one hydroxycarboxylic acid selected from succinic acid or an alkali salt thereof, preferably sodium citrate or potassium citrate, to a reactive polynuclear ferric iron compound in a preferred ratio. As a result, we succeeded in creating an iron composite that satisfies these requirements, and completed the present invention. The present invention has an iron content of 35-47
In terms of weight percent, the administered iron is hardly excreted in the urine and contains virtually no free iron, providing a parenteral iron preparation with extremely high stability and safety. According to the present invention, a ferric iron polynuclear olated product;
When the 2W/V% solution is left at 4℃ for 7 days, no precipitation occurs, and the average molecular weight determined by the number of reducing ends measured by the Somogyi-Nelson method is 2500~
10,000, preferably 3,500 to 6,000 dextrin (hereinafter simply referred to as dextrin) is selected from 0.75 to 1.60 mol (glucose residue units, hereinafter the same) per 1 mol of iron, and citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid. 0.02 to 0.20 mol, preferably 0.05 to 0.16 mol of hydroxycarboxylic acid (hereinafter simply referred to as hydroxycarboxylic acid) or an alkali salt thereof, preferably citric acid or its sodium salt or potassium salt, per mol of iron. At least one alkali carbonate selected from sodium carbonate or potassium carbonate is mixed with water and heated to 100°C to 130°C, preferably 102°C in a container that can be heated and stirred.
A crude dextrin/hydroxycarboxylic acid/ferric polynuclear complex solution is obtained by heating and stirring at a temperature of -120°C for 1 to 5 hours. The crude dextrin/hydroxycarboxylic acid/ferric polynuclear complex solution obtained by the above method is filtered, and at least one lower alkyl alcohol selected from methyl alcohol, ethyl alcohol, and isopropyl alcohol is added. The complex is then precipitated and centrifuged,
Repeat this process if desired to obtain purified dextrin.
A hydroxycarboxylic acid/ferric polynuclear complex is obtained. The complex containing the lower alkyl alcohol water is then dried with warm air or reduced pressure, crushed if desired, and stored to prepare a parenteral iron preparation at the time of use. This purification step is effective in removing unreacted hydroxycarboxylic acid alkali salts, free iron, low iron content complexes, and low-molecular complex parts, and improves the stability of the complex of the present invention.
Helps improve safety. The polynuclear olated product of ferric iron used in the present invention is, for example, a suspension formed by slowly adding an excessive amount of an aqueous alkali carbonate solution dropwise to an aqueous ferric chloride solution while stirring well at cold or room temperature. It is relatively easily prepared by washing with distilled or pure water, filtering, or centrifuging. In the ferric polynuclear product obtained in this way, electrolytes that interfere with coordination bonds with other components and cause a decrease in iron content are removed as much as possible. Preferably, by following the above method, such conditions can be achieved relatively easily and more economically than by performing ion exchange, dialysis, etc. Furthermore, the hydroxycarboxylic acid or alkali salt thereof used in the present invention and the amount used have important meanings. That is, by using hydroxycarboxylic acid or its alkali salt as a component of the complex of the present invention, it imparts a negative charge to the target substance, and its stability in solution is dramatically improved compared to the dextrin/ferric iron complex. . In particular, when the alkali citrate salt is used in an amount ranging from 0.02 to 0.20 mol, preferably from 0.05 to 0.16 mol, per mol of iron, the most remarkable improvement in stability in solution is observed. Furthermore, as the amount of the alkali hydroxycarboxylic acid salt reacted increases, the molecular weight of the resulting composite tends to decrease, and therefore, it also has the significance of controlling the molecular weight of the composite. Furthermore, as is clear from the experiments described later, the amount of dextrin in the composite of the present invention greatly affects the stability of the composite in solution, and generally, as the amount of dextrin increases and the powder iron content decreases, the amount of free iron decreases. The result is that stability and safety generally decrease. On the other hand, it is not preferable to reduce the amount of dextrin to an extremely low level since this will reduce the water retention of the complex and its stability in solution. Therefore, the present invention is characterized in that the amount of dextrin is kept to the necessary and minimum amount, the complex has a high iron content, and hydroxycarboxylic acid is used to compensate for the decrease in hydrophilicity of the complex. Therefore, it is preferable that the complex of the present invention contains dextrin in an amount that does not reduce the stability of the complex in solution and that allows a complex with a suitably high molecular weight to be obtained. 0.75 to 1 mole of iron
By using 1.6 moles (glucose units) of dextrin, a complex satisfying these conditions is obtained. The dextrin/hydroxycarboxylic acid/ferric polynuclear complex thus obtained is a dark brown, odorless, amorphous powder that gradually dissolves in cold water and easily dissolves in hot water, and once dissolved, it precipitates even when cooled. The result is a stable solution. Moreover, this solution is sufficiently stable near neutrality. Ethanol/methanol/
Almost insoluble in organic solvents such as acetone and ether. Furthermore, this complex is a polymer complex that has a negative charge and a molecular weight distribution with a number average molecular weight of about 140,000 as measured from osmotic pressure. The iron composite produced according to the present invention has the following characteristics. 1. Due to its high iron content, it is extremely advantageous in terms of formulation and storage. 2. When administered intravenously, the bone marrow,
It is taken up by endothelial cells such as the liver and spleen, and does not exhibit cumulative effects in the blood like ferric dextran. 3. The aqueous solution of this complex is stable around neutrality, and therefore there is no risk of damaging biological tissues. 4. Since the components other than the iron component that make up this complex are all metabolizable substances, such as dextrin and hydroxycarboxylic acid, there is no accumulation during administration.
No other serious side effects were observed. 5. Since it has extremely high storage and thermal stability in the form of a solution, it is extremely advantageous during preparation sterilization and during storage and distribution stages. The toxicity and pharmacological effects of the complex obtained by the production method of the present invention were investigated. When the acute toxicity of the dextrin-citrate-ferric polynuclear complex of the present invention was investigated using 8 male mice per administration group, the LD ₅₀ after intravenous administration was approximately
It showed 460mgFe/Kg, and more than 2500mgFe/Kg when administered subcutaneously. In addition, six male guinea pigs were sensitized by injecting 10 mg Fe/Kg of the complex into the abdomen or rear neck subcutaneously three times every other day, and 3 weeks later they developed systemic anaphylaxis and were similarly sensitized. Investigating Schltz-Dale reactions using guinea pig ileum,
Antigenicity was investigated, but all tests were negative. The dextrin-citric acid-ferric polynuclear complex of the present invention using ⁵⁹ Fe containing 250 mg of iron was mixed with 20 W/V% glucose and injected intravenously to patients with agastric iron deficiency anemia. We investigated the dynamics of According to the blood iron loss curve, the iron half-life is approximately 29 minutes, and the red blood cell iron utilization curve is
It continued to rise until the 14th, and the iron utilization rate was over 70%. In addition, the distribution of ⁵⁹ Fe in the body, determined by radioactivity measurements on the body surface, is highest in the liver after 24 hours, followed by bone marrow and spleen, reaching the highest level in bone marrow after 3 to 4 days, and decreasing in the liver to almost no level. Therefore, an increase in the number of counts in the heart, which indicates the concentration in the blood, was observed, and it was observed that the drug was being utilized by red blood cells. In addition, 55 patients with iron deficiency anemia due to gynecological diseases received 1 to 2 tubes per day (1 tube, 2 ml) of the dextrin/citric acid/ferric polynuclear complex of the present invention, depending on the symptoms.
110-145 mg (50 mg as iron) sorbitol 80 mg,
After intravenously or intramuscularly injecting an appropriate amount of distilled water for injection 2 to 7 times a week, 38 cases showed an increase in hemoglobin level of 1.5 g/dl or more, 1.4 to 1.0 g/dl.
12 cases of dl, 5 cases of less than 1.0g/dl,
Significant improvement in anemia was observed in most cases. No side effects were observed in all cases, including symptoms of acute iron toxicity,
No allergic symptoms or liver dysfunction were observed. The complex obtained by the production method of the present invention can be dissolved in distilled water and used as it is, preferably with a non-reducing isotonizing agent such as salt, hexites such as sorbitol and mannite, or polyhydric alcohols such as glycerin and ethylene glycol. An injection can be prepared by adding an appropriate amount of at least one of the following. Example 1 A small amount of 185 g of a newly produced polynuclear olated ferric iron (0.25 mol in terms of iron atoms), 34 g of dextrin with a molecular weight of 5000, 7.4 g of sodium citrate dihydrate, and 2.8 g of anhydrous sodium carbonate was added. The mixture was charged into an autoclave with water, stirred well, and reacted at 120°C for 2 hours with stirring. A crude dextrin/citric acid/ferric polynuclear complex solution with a dark brown color was obtained. Add 500ml of water to the solution and filter it,
Water-insoluble matter was removed. Add water to the filtrate and make up the entire volume.
After the volume was adjusted to 1000 ml, 640 ml of methyl alcohol was added to precipitate the product. After standing for a while, the supernatant was discarded, and the precipitate was centrifuged. 350 ml of water was added to the resulting precipitate, and the mixture was dissolved by heating in a boiling bath. After cooling, pulp filtration was performed, and water was added to the filtrate to make 600 ml.
By adding 600 ml of ethyl alcohol to the solution and allowing it to stand for a while, remove the supernatant and centrifuge.
A cake-like purified dextrin/citric acid/ferric polynuclear complex containing ethyl alcohol water was obtained. After drying the precipitate under reduced pressure over calcium chloride at room temperature,
The dried product was pulverized to obtain 26.3 g of a dark brown powdered dextrin/citric acid/ferric polynuclear complex.
Iron content 43.5% by weight, yield (based on iron)
81.4% by weight. Example 2 78g of newly produced ferric iron polynuclear compound (5.6 as iron)
g), 19.5 g of dextrin with a molecular weight of 5100, 2.9 g (0.01 mol) of sodium citrate dihydrate, and 1.2 g of anhydrous sodium carbonate were stirred together with a small amount of water in a simple glass autoclave and reacted at 115°C for 3 hours to produce dextrin and citric acid. A concentrated solution of acid-ferric polynuclear complex was obtained. After adding 200 ml of water, it was filtered, and water was added to the filtrate to adjust the total volume to 400 ml. 285 ml of methyl alcohol was added to this to precipitate the complex, which was then centrifuged. After separation, the precipitate is poured into water.
After heating and dissolving in 150 ml and cooling, precise pulp filtration was performed, and water was added to the filtrate to adjust the total volume to 230 ml. 250 ml of ethyl alcohol was added to this to precipitate the complex, and the mixture was centrifuged. The obtained precipitate was dried over calcium chloride under reduced pressure to obtain 10.4 g of a dextrin/citric acid/ferric polynuclear complex. Iron content 43.0% by weight, yield (based on iron) 80.4% by weight. Example 3 In place of the sodium citrate dihydrate used in Example 2, 1.0 g of sodium glycolate (0.01
11.9 g of dextrin/glycolic acid/ferric polynuclear complex in the same manner as in Example 2 using
I got it. Iron content 38.7% by weight, yield (based on iron) 82.1% by weight. Example 4 10.9 g of dextrin/gluconic acid/ferric polynuclear complex was prepared in the same manner as in Example 2, using 2.2 g (0.01 mol) of sodium gluconate instead of sodium citrate dihydrate in Example 2. I got it. Iron content 42.8% by weight, yield (based on iron) 83.9% by weight. Example 5 Using 2.3 g (0.01 mol) of sodium tartrate dihydrate instead of sodium citrate dihydrate,
Dextrin, tartaric acid,
11.0 g of ferric polynuclear complex was obtained. Iron content 42.1% by weight, yield (based on iron) 82.1% by weight. Example 6 10.8 g of dextrin/malic acid/ferric polynuclear complex was obtained in the same manner as in Example 2 using 1.8 g (0.01 mol) of sodium malate instead of sodium citrate dihydrate. . Iron content 39.3% by weight, yield (based on iron) 75.0% by weight. Thermal stability test Dextrin, citric acid, and
An aqueous solution with an iron concentration of 25 mg/ml was prepared from each dextrin/ferric polynuclear complex prepared according to Example 2 without adding the ferric polynuclear complex and sodium citrate dihydrate, but under all other conditions. was prepared, filled into an ampoule, and the ampoule was heated to 100°C to conduct a thermal stability test. The thermal stability of each sample was compared and determined from the appearance and electrophoresis experiment every 25 hours. As a result of the above test, no abnormality was observed in the appearance of the dextrin-citric acid-ferric polynuclear complex sample even after 200 hours, and the electrophoretic condition was good, but sodium citrate was not added. In the dextrin/ferric polynuclear complex sample, gelation occurred in 25 hours, and origin residues were also observed in electrophoresis. Similar experiments were conducted with hydroxycarboxylic acid alkali salts that can be used in the present invention other than sodium citrate. Although they are slightly inferior to sodium citrate, they have better thermal stability than dextrin/ferric iron complexes. Significant improvement was seen. Note that the thermal stability test conducted below was conducted under the same conditions as the above method. Examples 7 to 11 0.01, 0.02, 0.10, 0.15, respectively for iron component
Sodium citrate dihydrate having a molar ratio of 0.3 was added to 146 g of a new ferric polynuclear olate (as iron).
0.2 mol), 42 g of dextrin with a molecular weight of 5,600, and 2.3 g of anhydrous sodium carbonate under the same conditions, substantially according to the method of Example 1 above, and the obtained dextrin-citric acid-ferric polynuclear complex, The yield, iron content, and thermal stability were investigated. The results are shown in Table 1.

[Table] The complex of the present invention can be produced by coordinating hydrophilic dextrin and hydroxycarboxylic acid with hydrophobic ferric polynuclear chains, so that dextrin, hydroxycarboxylic acid, and hydroxycarboxylic acid, which can stably branch in water, Although it is presumed to form a ferric iron polynuclear complex, it is a polymer that contains some free dextrin and has a molecular weight distribution. Regarding the complex of the present invention, its elemental composition, residue composition, infrared absorption spectrum, molecular weight, particle size distribution,
The results of measurement experiments such as electrophoresis, thin layer chromatography, intrinsic viscosity, polarography, and gel filtration are shown below. a Elemental composition (measurement method) Γ Iron content analysis: After the sample is decomposed with hydrochloric acid, it is reduced with zinc dust to produce ferrous ions, and then redox titrated with ceric ammonium sulfate using o-phenanthroline test solution as an indicator. It was measured by the method. Γ Sodium content analysis: Measured using a flame photometer. (Results) The measurement results shown in Table 2 were obtained by the above method.

[Table] b Residue composition (measurement method) Γ Ferric polynuclear complex residue [FeOOH] _o : Calculated from the above iron content. Γ Dextrin residue [C ₆ H ₁₀ O ₅ ] _n and free dextrin [C ₆ H ₁₀ O ₅ ] _l : Hydrolyze each sample with hydrochloric acid, quantify the total dextrin as glucose by Bertrand method, and convert it to the amount of dextrin. did. The free dextrin content can be determined by coprecipitating the complex part with an excess amount of a positively charged colloid titration reagent methyl glycol chitozan solution, taking advantage of the fact that the complex part of the complex of the present invention has a negative charge. After precipitating the excess methyl glycol chitozan by adding a negatively charged colloidal titration reagent polyvinyl potassium sulfate solution, the free dextrin remaining in the supernatant was hydrolyzed with hydrochloric acid to produce glucose, and Bertrand The amount of dextrin was determined by the method and converted into the amount of dextrin. The difference between the total dextrin content and the free dextrin content was defined as the dextrin residue content. Γ Citric acid residue [C ₆ H ₅ O ₇ ]: After each sample is hydrolyzed with 6N hydrochloric acid, iron is allowed to flow down through a column packed with a strongly acidic ion exchange resin (Amberlite IR-120) and interferes with the measurement. The solution was concentrated to dryness, then dissolved in ethanol water, transferred to a conductivity titration cell, and conductivity titrated with a 0.1N NaOH solution.
The amount of citric acid residue was determined from the amount of . (Results) The measurement results are shown in Table 3.

[Table] c Infrared spectrum (measurement method) Measured using an infrared spectrophotometer (Model EPI-G3 manufactured by Hitachi, Ltd.) using the potassium bromide tablet method. (Results) The infrared absorption spectra of the samples measured were in good agreement with each other, and as a representative example, the infrared absorption spectra and characteristic absorption attributes of the composite of Example 1 are shown in Figure 1 and Table 4. .

【table】
derived from residues

Claims (1)

[Scope of Claims] 1. The presence of dextrin and at least one hydroxycarboxylic acid or alkali salt thereof selected from citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid in the presence of an alkali carbonate in a polynuclear olated form of ferric iron. Below, a method for producing a dextrin/hydroxycarboxylic acid/ferric polynuclear complex comprising reaction at 100 to 130°C. 2. The manufacturing method according to claim 1, wherein the hydroxycarboxylic acid or its alkali salt is used in an amount ranging from 0.02 to 0.20 mol, preferably from 0.05 to 0.16 mol, per 1 mol of iron. 3. Dextrin is a 2W/V% solution at 4℃.
No precipitation occurs when left for 7 days, and the average molecular weight determined by the number of reducing ends measured by the Somogyi-Nelson method is 2,500 to 10,000, preferably
3,500 to 6,000 dextrin, the manufacturing method according to claim 1. 4 Dextrin is 0.75 to 1.60 per mole of iron
The method according to claim 1, wherein the amount is in the range of moles (glucose residue units). 5 Add dextrin and at least one hydroxycarboxylic acid or alkali salt thereof selected from citric acid, gluconic acid, tartaric acid, malic acid, and succinic acid to the ferric polynuclear olated product in the presence of an alkali carbonate at 100 to 130°C. A method for producing a dextrin/hydroxycarboxylic acid/ferric polynuclear complex, which comprises reacting with dextrin and removing free dextrin from the obtained complex. 6. The production method according to claim 5, wherein the hydroxycarboxylic acid or its alkali salt is used in an amount ranging from 0.02 to 0.20 mol, preferably from 0.05 to 0.16 mol, per mol of iron. 7. Dextrin, its 2W/V% solution at 4℃
No precipitation occurs when left for 7 days, and the average molecular weight determined by the number of reducing ends measured by the Somogyi-Nelson method is 2,500 to 10,000, preferably
The manufacturing method according to claim 5, wherein the dextrin has a molecular weight of 3,500 to 6,000. 8 Dextrin is 0.75 to 1.60 per mole of iron
6. The manufacturing method according to claim 5, wherein the amount is in the range of moles (glucose residue units).