FR2534589A1 - PROCESS FOR THE PREPARATION OF A PHARMACEUTICAL USE SOLUTION CONTAINING A NEW FER III POLYNUCLEAR MIXED COMPLEX AS ACTIVE INGREDIENT - Google Patents

Abstract

PROCESS FOR THE PREPARATION OF A SOLUTION FOR PHARMACEUTICAL USE CONTAINING A NEW MIXED POLYNUCLEAR FERIII COMPLEX AS ACTIVE INGREDIENT. THE PROCESS ACCORDING TO THE INVENTION IS CHARACTERIZED IN THAT FRESHLY PRECIPITATED AND WASHED FERIII HYDROXIDE IS DISSOLVED IN ACETIC ACID, THE FERIII ACETATE OBTAINED IN THIS WAY IS PUT TO REACT WITH SUGAR ACID (0.25 TO 0.5 EQUIVALENT) AND DEXTRANE (0.25 TO 0.5 EQUIVALENT) OR WITH SUGAR ACID (0.5 TO 1.0 EQUIVALENT), THEN ACID ACETIC FORMED DURING THE REACTION IS ELIMINATED BY WATER VAPOR DISTILLATION, WATER VAPOR DISTILLATION CONTINUES UNTIL THE PH OF THE SOLUTION REACHES A VALUE OF 4.5 TO 5.0, THEN THE REQUIRED CONCENTRATION OF IRON IS SET BY VACUUM DISTILLATION, THE SOLUTION IS THEN STERILIZED AND, POSSIBLE, ADDITIVES OR ADDITIVES ARE ADDED.

Description

The present invention relates to a method for

  preparation of a solution for pharmaceutical use

  holding a new polynuclear mixed complex, electrically

  neutral, iron (III) as the active ingredient.

  It is known that many iron-based compositions are used for the treatment of "iron deficiency" diseases. In the case of significant iron deficiency,

  parenteral administration of iron can be performed.

  However, ionic iron can not be administered

  parenterally because the proteins are precursor

  Thus, compositions for parenteral administration contain organic iron complexes. In addition to the application to humans, these products are of great therapeutic value.

veterinary.

  The preparation and control of the P H of the iron for injection complex solution has heretofore been carried out with strong mineral alkalis. Such methods are, for example, those described in Canadian Patent No. 665,410 and Egyptian patent No

52,363, respectively.

  A major disadvantage of these processes is that the eli-

  In addition, ionization requires dialysis (eg, US Pat. No. 3,234,209), ion exchange (eg, Canadian Patent No. 665,410) or precipitation.

  by an organic solvent (British Patent No. 1,149,137).

  It is known that in solutions for injection containing iron, iron is present in the form of a

  complex with a type of ligand (eg British patent

  N O 1 149 137) or with two different organic ligands

  A good example of this latter case is the product described in Belgian Patent No. 689,779. The major disadvantage of the compositions so far used is that the iron injected into the tissues comes into circulation in a random manner. and uncontrollable, can not be eliminated in this manner It is also known from the published technical literature that even the most recent preparations can not meet the basic requirement that tissue iron absorption be approximately stable. -Magyar Allaorvosok Lapja 35,

444 (1980) 7.

  An object of the present invention is to find a process which eliminates the disadvantages of the methods known hitherto, and which the prepared iron complex releases.

  iron in several stages in a regulated way, in vivo.

  Another object of the invention is to prepare a complex of

  iron that maintains an approximately isotonic solution.

  The method according to the invention is based on the discovery of

  the interaction between iron (III) and organic ligands (polyalcohols and their derivatives, for example

  dextran and sugar acid) is related to libera-

  Proton ration in aqueous solution This is the result

  deprotonation of the organic ligand and some.

  linked water molecules in the iron hydrate sphere (hydroxo mixed complex formation) The hydroxo-ligand content of the mixed complex can be determined by potentiometric measurement This content has been found to be

  2.0-2.6 hydroxide radicals per iron atom.

  In the text of the text the sugar acid ternae denotes an acid

  carboxylic acid derived from a monosaccharide.

  The protons released in the above reaction must be neutralized to obtain the desired pH of the solution for injection, i.e., pH above 4.5. iron is the ferric acetate for this system This acetate is protonated by protons released during the formation of the mixed complex The formed acetic acid can be removed from the system by steam distillation In this way, it is possible to introduce cations (eg alkali metal ions) without any danaer into the system during

  the neutralization operation that ensures the desired p H of the solution.

  The iron atom from iron acetate will be the atom

2 535489

  -3- Central of the electrically neutral mixed complex The excess iron III precipitates in the form of ferric hydroxide

  and can be separated by centrifugation.

  On the basis of the findings specified above, the invention relates to a process for the preparation of a

  solution containing a mixed polynuclear elec-

  tri-neutral, iron (III) as the active ingredient.

  According to this process, iron (III) hydroxide freshly precipitated and washed so as to be free of anions is dissolved in acetic acid, the iron (III) acetate obtained is reacted with an acid of sugar (0-25 0.5 equivalent) and dextran (0.25-0.5 equivalent) or with a sugar acid (0.5-1.0 equivalent) The acetic acid formed during the reaction is distilled off with steam, which is continued until the pH of the solution is 4.5 to 5.0. The required iron concentration is adjusted by vacuum distillation. The solution is then sterilized and eventually

add additives or adjuvants.

  In a preferred embodiment of the process according to the invention, lactobionic acid, gluconic acid or maltobionic acid are used as the acid.

sugar.

  The optimal concentration ratio of iron and organic ligand could be determined by repeated preparation of the new kind of solution by mixing

  different proportions of iron and organic ligand.

  To dissolve 1 unit of iron (1 mole), it takes at least a quarter of a unit of sugar acid (0.25 mole), and if one calculates the dextran content using the mesh of glucopyranose of 12 atoms of carbon, it takes 0, 25 units of dextran By using this ratio, one can prepare a

  solution of 100 mg Fe / cm 3 (1.786 mol / dm 3) According to the

  As a result, the organic ligand content of the solution can be increased from 0.25-0.25 units to 0.33-0.33 units with no significant change in the biological effect and chemical properties of the preparation. Dextran can precipitate from the solution prepared in this way, especially at temperatures below room temperature.

  a disruptive effect In addition, a lower con-

  organic ligand concentration would lead to a precipitate

  material containing iron.

  The concentration of acetate in the system, ie

  the number of iron bound ligand acetate ligands can be determined by potentiometric titration after steam distillation of excess acetic acid. For an iron unit (1 mole) there is 0.13- 0.2

acetate unit in the solution.

  Thus, the active ingredient of the solution prepared in the above manner is an electrically neutral mixed complex of iron (III) in which four types of ligands (sugar acid, dextran, acetate and hydroxide) are bound

  by coordination to the central iron atom.

  For treatment of humans, iron-containing injections of Fe mg / cm 3 or lower are generally required. Such injections may be prepared according to the invention as indicated above or analogous way; however, lactobionic acid must be substituted for all dextran. The active ingredient of an injection solution prepared in the latter manner is a mixed polynuclear electrically neutral (non-ionic) iron (III) complex with an iron atom The central iron atom of this complex binds lactobionate, acetate and hydroxide ligands.

  The homogeneity of the iron complex, i.e.

  active ingredient of the solution for injection, the degree of oxidation and the iron spin can be proved by the spectrum of M 6 ssbauer (resonant absorption of gamma rays) -5-

  ice obtained by rapid freezing of the solution.

  The Mossbauer spectrum shows (Figure 1) that part of the iron- (III) is reduced during the preparation Part a of the spectrum represents a solution free of iron (II), while part b of the spectrum represents a solution containing 4.7% iron (I,) As the iron (II) formed is also present in the mixed complex, the biological effect is not impaired by the reduction not

not exceeding 5-6%.

  Parameters-spectrum of M 5 ssbauer / -fer (III)

  isomer displacement δ 0.45 mm / s relative to metal iron

  The quadrupole division * 0.83 mm / s_ 7 unambiguously indicates a high spin central iron (III) atom attached to the oxygen donor atoms. The observed line width (10.57 mm / s) refers to the equivalence of iron atoms in the polynuclear complex The intensity of the parts of the spectrum attributed to iron (III) and

  iron (II) indicates the ratio of iron (III) to iron (11).

  The parameters of the iron lines (II) / iso-

  mother 1,18 mm / s, quadrupole division: 3,20 mm / s_ 7 are characteristics of atom of iron (II) of spin

high bound in the complex.

  The iron (II) content of the solution prepared by the process according to the invention did not exceed 5.0% of the

total amount of iron.

  The iron content of the complex molecule (number

  of central atoms of iron, in a molecule) forming the

  The active ingredient of the solution for injection prepared by the process according to the invention can be calculated from the value of the osmotic pressure if the total iron content of the solution is known (this can be determined by complexometric measurements). osmotic pressure of a solution for injection containing the minimum concentration of ligands needed to solubilise iron

3 -3

  (1.84 mole / dm iron: 0.46 mole / dm lactobionic acid and glucopyranose dextran mesh -6 equivalent to the latter) indicates a concentration of

0.23 mole / dm 3 for the complex.

  One molecule of the complex prepared by the process according to the invention contains 8 iron atoms. From the physiological point of view, it is a hypotonic solution. As a result, it is convenient to use the organic ligands in a slight excess (0.33 -0.33 units of iron instead of 0.25-0.25 units) to the preparation of the injection In this way, an almost isotonic solution can be obtained

  with osmotic pressure not above 400 mosms.

  For the active ingredient of the solution for injection

  prepared according to the invention, the complex mixed poly-

  According to the examinations mentioned above, a composition of Fe 8 L 2 D 2 Ac / OH / 21 In the formula: L is the ligand lactobionate (or another sugar acid) D is a shackle glucopyranose dextran and

Ac is the acetate ion -

  The molecular weight of the complex according to the composition

  above is 2226, the iron content is

, 13%.

  According to similar examinations, it has been found that the composition of the active ingredient of a dextran-free iron injection solution prepared according to the invention is: Fe 2 L Ac / OH / 4 The molecular weight of this composition is 597.0 O

Iron content is 18.76%.

  The starting material in the process according to the invention is iron (III) acetate. The iron (III) acetate prepared and maintained in the solid state loses, however, its solubility

  in water (and also in acetic acid).

  quence, a stock solution of iron (III) acetate in -7-

  acetic acid is used as the starting material.

  It is prepared by immediate dissolution in acetic acid of freshly prepared iron (III) hydroxide and

  washed in such a way as to be free from anions

  slow release of organic ligands is dissolved in this stock solution Excess acetic acid, which comes from the starting stock solution and reaction between protons released during complex formation and iron acetate anions is distilled from the solution by steam distillation. Steam distillation is continued until

  the desired pH is reached.

  vacuum solution to concentrate the solution until the desired iron concentration (100 mg Fe / cm 3) is

obtained.

  The solution prepared by the process according to the invention can be used after satisfactory sterilization. Water-soluble additives having an adjuvant effect (for example vitamin B 12) can be dissolved in this solution, if necessary. The solutions also contain 0 , 0.2% of preservatives (for example phenol,

  benzyl alcohol) and additives for the iso-

  tonic (eg sodium chloride, sorbitol, etc.).

  The chemical characterization of the solution prepared according to the invention is based on determinations of the iron content by complexometric titration, of the p H by potentiometric measurement, of the osmotic pressure which reflects the molarity, of the M 8 ssbauer spectrum relating to the degree of oxidation and spin of the central iron atom, of the acetate content by potentiometric titration after steam distillation and the content of

dry gravimetrically.

  The solution for injection, prepared by the method according to the invention and sterilized for 30 minutes at 1000 ° C., injected into the crural muscle of aged pigs for two months at a dose of 100 and 200 mg of Fe per kg

  body weight did not cause a local reaction

  No prolonged absorption is observable In tissues, the presence of iron can be detected even after 21 days at the site of infection.

  By administering a single injection intra-

  muscle, this preparation maintains the iron supply for newborn pigs during their first 3 weeks. The most important advantages of the solution prepared by the process according to the invention can be summarized as follows. An electrically neutral (nonionic) polynuclear mixed complex can be prepared from the constituents indicated, by the process according to the invention. of a high spin of the molecule are connected in part by organic ligands and partly by hydroxide and oxygen bridges There are at least three, in the optimal case four ligands (sugar acid, dextran) In spite of its polynuclear nature, the complex does not exhibit superparamagnetism as evidenced by

the spectrum of M 3 ssbauer.

  The coordination sphere formed with several ligands ensures that the iron is released in vivo in several stages by the complex. This results in a more prolonged absorption and a lower toxicity than those observed with commercially available preparations. -ionic and the resulting low osmotic pressure, the complex does not cause

  of local sensitivity despite its high iron content.

  From the solution prepared by the process according to the invention, solutions for injection can be produced directly. It is not necessary to prepare a solid form of the mixed complex which is the active ingredient. It is also necessary to eliminate ions from the solution for injection by dialysis, ion exchange or in any other way. These facts make the technological operation simpler and less costly. The process according to the invention is illustrated by the

  In these examples, the following is described:

  paration of solutions for injection of a volume of

3 3

  cm 3 and a concentration of 100 mg Fe / cm With

  proportional increase in the quantity of

  In addition, larger volumes may also be

products, as needed.

Example 1

  a) Preparation of the starting stock solution, iron acetate (III) in acetic acid 54.06 g of FeCl 3 O 6 H 2 O are dissolved by heating moderately in about 12 cm 3 of 99.5% acetic acid. of iron (III) acetate in acetic acid is

  a thin stream in 100 cm 3 of 25% NH 4 OH solution.

  This mixture containing: the precipitated iron hydroxide (III) contains excess ammonia The solution which has heated during this reaction is then filtered hot by gentle suction and the iron hydroxide (III) collected on the filter is washed with hot distilled water to be stripped of chloride ions The presence of chloride ions is verified by reaction with silver nitrate X The fresh, still wet precipitate is dissolved from the filter by means of 50 cm 3 of acetic acid to

  99.5% warm If the solution is cloudy, it is

  fugue and the clear solution is used for the preparation

of the iron complex.

  It is convenient to prepare multiple volumes of the stock solution. The iron acetate (III) in acetic acid can be stored without precipitation for a period of time.

quite a long time.

  The iron (III) content of the prepared solution of

  this way is determined with Accuracy by com-

  plexometry As a consequence of the dilution and possible losses during the preparation, the iron content

will be 1-1.2 mol / dm 3.

  b) Preparation of the solution for injection From the iron (III) acetate stock solution prepared and analyzed for the iron content as described in part (a), a volume equivalent to 100 cm. 3 solution of iron (III) at 1.786 mol / dm 3 (100 mg Fe / cm) is measured in a 1-liter flask of a steam distillation apparatus.

  this solution amounts to 21.301 g of lactose

  bionic and 19.279 g of dextran, measured with analytical precision These materials dissolve in the solution containing iron in two days at room temperature The acetic acid formed in the reaction between

  the iron atoms and the ligands are removed by distillation.

  The steam distillation is continued until the pH of the solution is 4.7 to 4.9. The solution is then concentrated to 100 cm 3 by vacuum distillation. The iron content of the solution obtained in this way is determined by complexometry

  and the osmotic pressure of the solution is also measured.

  The spectrum of M 6 ssbauer of amorphous ice obtained by rapid freezing of a few drops of the solution is

  recorded at the temperature of the liquid air.

Example 2

  Each step of the process is repeated as described in Example 1, except that in the volume of the iron acetate (III) stock solution, prepared as described in part a) of Example 1 which is equivalent to cm 3 of iron solution with a concentration of 1.786 mol / dm, 15.98 g of lactobionic acid

14.47 g of dextran.

-11-

Example 3

  Each step of the process is carried out as described in Example 1, except that in the volume of the iron acetate stock solution (III), prepared as described in part a) of Example 1, which is equivalent to cm 3 of iron solution with a concentration of 1.786 mol / dm 3, 8.76 to 11.68 g of lactobionic acid and 14.47 to 19.29 g of dextran are dissolved. preparation

  as described in part (b) of example 1.

Example 4

  Each step of the process is carried out as described in Example 1, except that in the volume of the iron acetate (III) stock solution, prepared as described in part (a) of Example 1, which is equivalent to 100 cm of iron solution with a concentration of 1.786 mol / dm, 15.54 to 20.72 g of maltobionic acid and 1.47 to 19.29 g of dextran are dissolved.

  as described in part (b) of example 1.

Example 5

  Each step of the process is carried out as described in Example 1, except that in the volume of the iron acetate (III) stock solution, prepared as described in part (a) of Example 1, which is equivalent to cm 3 of iron solution with a concentration of 1.786 mol / dm, 35.17 g of lactobionic acid is dissolved. The preparation is continued as described in part b)

of Example 1.

Example 6

  Each step of the process is carried out as described in

  Example 1, except that after concentration by dis-

  Vacuum distillation, dissolved in the solution 100 g / cm 3

  hydroxy-cobolamine as adjuvant.

-12-

Claims (3)

  An aqueous solution of an iron complex of the formula Fe 8 L 2 D 2 Ac / OH / 21 wherein L is a lactobionate ligand or sugar acid, D is a glucopyranoside dextran mesh and Ac is the acetate ion.   2 A process for preparing a solution for   pharmaceutical use containing a mixed poly-   electrically neutral nuclear iron (III) as the active ingredient, characterized in that freshly precipitated and washed anion-free iron (III) hydroxide is dissolved in acetic acid, Iron (III) acetate obtained in this manner is reacted with a sugar acid (0.25 to 0.5 equivalent) and dextran (0.25 to 0.5 equivalent) or with a sugar acid (0). 5 to 1.0 equivalents), then the acetic acid formed during the reaction is removed by steam distillation, the steam distillation is continued until the pH of the solution reaches a value of 4.5 to 5.0, then the required concentration of iron is adjusted by vacuum distillation, the solution is then sterilized and optionally additives or adjuvants.   A process according to claim 2, characterized   in that, as sugar acid, lactobutic acid is used   bionic, gluconic acid, maltobionic acid.