DE3531279A1 - D,L-lysine salt of 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indole-3-acetic acid, process for its preparation and pharmaceutical preparations which contain the same - Google Patents

Description

Dr. Walter Nielsch Patent attorney:

SlrJusweg43,2000Hamburg95 j 3531279

Telephone: 504166 I "3 -

D, L-lysine salt of 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3 ~ acetic acid, Process for its manufacture and pharmaceutical preparations containing the same.

Sigma-Tau Industrie Farmaceutiche Riunite S.p.A., Viale Shakespeare 47, 1-00144 Rome (Italy)

The present invention "relates to the new chemical compound D, L-lysine salt of 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3-acetic acid, a process for its manufacture and anti-inflammatory pharmaceutical preparations containing the salt as contain active ingredient.

The anti-inflammatory, antipyretic and analgesic properties of 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3-acetic acid or indomethacin are known, making this compound particularly useful in the treatment of rheumatoid arthritis , Bechterew's disease ¹ (ankylosing spondylitis), gouty arthritis, osteoarthritis.

In general, indomethacin is well tolerated, but it can have toxic and side effects, preferably in the gastrointestinal tract. These unfavorable effects are at least partly due to the water insolubility of indomethacin, whereby it is impossible to use pharmaceutical preparations for parenteral administration. Oral and rectally administrable preparations are currently available on the market, but these often show an undesirable aggressive effect against the mucous membrane of the Stomach and intestinal tract.

To overcome these problems, water-soluble salts are used Indomethacins with natural amino acids such as lysine and arginine, as well as with amines such as N-methyl-D-glucamine, have been around for a long time Time has been synthesized.

For example, in French patent application 7305161, PR-OS 22 17 003, filed on February 14, 1973 by the applicant Instituto de Investigaciones Terapeutical S.A., the manufacture

of water-soluble salts of indomethacin with lysine and arginine described. In the patent specification, however, it is not specified whether the salt by reacting the indomethacin with L-, D- or D, L-lysine is obtained. However, by comparing the Melting point of the salt, the preparation of which is given in Example 2 of FR-OS, with the melting point of the compound of these Invention found that the compound of FR-OS is the salt with L-lysine. This is easy to see when you consider that the L-isomer is not only the form in which the amino acid occurs naturally, but also the form available with the lowest cost is.

It has now been found, surprisingly, that the D, L-lysine salt 1- (4-chlorobenzoyl) -5-metho2 ^ -2-methyl-1H-indole-3-acetic acid of formula A

NH ₂ -CH ₂ - (CHg) ₃ -CH COOH

NH

(I)

(II)

wherein (I) is the anion of the acid and (II) is the cation of D, L-lysine, is remarkably more water-soluble than the corresponding, already known L-lysine salt. Thus, the solubility of the L-lysine salt with 7.6 g / liter in distilled water was determined at 26 ⁰ G, while the solubility of the D, L-lysine salt of the invention 12.5 g / liter in distilled water is at 26 ⁰ C.

A process for the preparation of the D, L-lysine salt of 1- (4-chlorobenzoyl ) -5-methoxy-2-methyl-1H-indole-3-acetic acid includes the

Stages:

(1) contacting equimolar amounts of 1- (4-chlorobenzoyl) -5Hmethoxy-2-methyl-1H-indole-3-acetic acid and D, L-Ly.sinbase in a reaction solvent, whereby a crude product the compound of formula (A) is obtained, which is separated from the reaction solvent, washed and in vacuo is dried;

(2) Dissolving the compound of step (1) in a hydroalcoholic Phase, increasing the temperature of the resulting solution to about 60 to 80 ° C, then rapid cooling of the solution about 10-5 ° C with vigorous stirring so as to obtain micronized crystals of the compound of formula (A), which are separated washed and dried under vacuum.

Because of its higher water solubility, the D, L-lysine salt of this invention is not only more suitable than the corresponding L-lysine salt for the production of parenterally administrable pharmaceutical preparations, but it is the indomethaoin derivative of choice for the production of an orally administrable pharmaceutical preparation in the form of a controlled release tablet. Preferably the structure of the controlled release tablet is used which is described in the European patent application 85 830 182.3 of July 16, 1985 by the same assignee of this invention has been described and claimed there. The disclosures of this European patent application are replaced by the Reference incorporated in the specification of this invention.

Briefly summarized, this controlled release tablet includes a Reservoir consisting of a solid matrix of a homogeneous mixture of a polymeric material, at least one metered Part of the active ingredient and an additive that is soluble in gastric juice under negative heat of solution, a coating on the solid Matrix-type reservoir of a first rate-controlling insoluble membrane that controls the release of the active ingredient according to the modulates desired kinetics; and a second protective membrane of a soluble polymeric material.

The present invention therefore also provides oral or parenteral

■ administrable pharmaceutical preparations available with anti-inflammatory, antipyretic and analgesic activities for the therapeutic treatment of rheumatoid arthritis, Ankylosing spondylitis, gout and Osteoarthritis with a therapeutically effective amount of the D, L-lysine salt 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3-acetic acid as an active ingredient and pharmacologically acceptable binders and carriers.

It was found that an appropriate dose of the D, L-lysine salt of indomethacin is between about 10 and about 70 mg / kg body weight / day.

Suitable unit dosage forms contain from about 100 to about 500 mg of the active ingredient.

Illustrated in the following non-restrictive examples Example 1 the preparation of the D, L-lysine salt of indomethacin and Example 2 shows the manufacture of tablets with a constant rate of release of the active ingredient.

example 1 Preparation of the D, L-lysine salt of indomethacin

(1) Salification reaction of indomethacin with D, L-lysine base.

Substantially equimolar amounts of D, L-lysine (crystals) (146 kg) and indomethacin (FU microcrystals) (4500 kg) are dissolved in acetone. The reaction mixture obtained was kept with stirring for 4 hours at 40 ^° C. in an enamel reaction vessel equipped with a heating jacket and stirrer. The crude reaction product was centrifuged, thoroughly washed with a 20 volume% solution of acetone in water (v / v) and does not border on Ainet 40 ⁰ C temperature in a drying oven under vacuum.

(2) Crystallization and purification of the crude D, L-lysine salt from Indomethacin.

This operation was carried out with the intention of micronizing

Obtaining crystals, not using mechanical devices, but by using chemical solvents to treat the active ingredient with careful dimensional uniformity that is essential to ensure the constant bioavailability of pharmaceutical preparations. 400 kg of crude D, L-lysine salt of indomethacin were in 95% Ethanol in a reaction vessel, equipped with a heating jacket and devices for rapid cooling and for vigorous stirring the contents of the reaction vessel, dissolved.

The solution was kept with vigorous stirring and heated brought to the boiling point of ethanol. There were 1000 Liters of deionized water were added and the solution was then rapidly cooled to 5 ° C, forming a precipitate, which is centrifuged off and washed with acetone and in a vacuum drying oven was dried at a temperature below 40 C.

300 kg (75% yield) of pure D, L-lysine salt of indomethacin was obtained with the following characteristics: Organoleptic characteristics: odorless, practically tasteless go, pale yellow microcrystalline powder.

Solubility: 12.5 g / liter of distilled water at 26 0, difficult soluble in alcohols. Practically insoluble in chloroform and esters.

Melting point: 204-207 ⁰ C (decomposition).

UV spectrum: The absorption spectrum of a 2 mg / liter (w / v) ethanol solution was measured in a cuvette with an optical distance of 1 cm measured; two absorption peaks were found at 267-1 nm and 321 ί 1 mn.

IR spectrum: The infrared absorption spectrum in Nujöl showed characteristic absorption peaks at the following wavelengths:

—1 —1

1680 cm "(amide carbonyl absorption); 1630 cm" (carboxylyl absorption); 1300 cm "(carboxyl ion absorption).

NMR spectrum:

DO, O 1.32-2.03 m 6H

2.15 s 3H (I ₃ )

- ο -

2.9 - 3.13 t 2H (1CH ₂ )

3.46 ε 2Η (I ₂ )

3.65 s 3H (1CH ₃ ) 3.7 - 3.86 t 1H (1CH) 6.16 - 6.56 m 2H (Arom) 6.9 - 7.46 m 5H (Arom)

Crystallographic identification: diffractometric-crystallographic Testing was carried out with a Philips diffractometer. The comparison of the diffraction spectra of indomethacin as such (1), D, L-lysine base as such and its reaction product showed beyond doubt that in the salt formation of (1) with (2) a new crystalline phase is formed that corresponds to a true, well-defined chemical compound.

Example 2 Manufacture of tablets with the D _t L-lysine salt of indomethacin

with a constant release rate of the active ingredient .

(a) Preparation of solid matrix-type reservoirs In order to prepare 1000 solid matrix-type reservoirs, the following products were used in the amounts indicated: D, L-lysine salt of indomethacin

(active ingredient) 100 g

Celiulose acetate propionate 10 g

(Average molecular weight ^ 75,000) • Eastman Kodak, 482-20 Type

Disodium phosphate 80 g

Mannitol 70 g

Talc 60 g

Magnesium stearate 3 g

The active ingredient, disodium phosphate, mannitol and talc were placed in a powder mixer and mixed carefully for as long as until a completely homogeneous mixture is obtained. A solution of the polymeric material in 55 ml of mixed solvent

Acetone / isopropanol 1: 1 was made. The above obtained The mixture was wetted with this solution ". The obtained Material was granulated through an 800 µm sieve, dried and then granulated again through a 420 ^ m sieve.

The granules obtained in this way were mixed with magnesium stearate and pressed using separate punches with a diameter of 12 mm at a pressure of 3000 kg / cm, thereby producing biconvex, lenticular solid matrix-type reservoirs.

The geometrical formations of such matrix-type reservoirs were the following:

Diameter 12 mm

Radius of curvature of the spherical segments that

the biconvex reservoir is 14 mm

Diameter: thickness ratio 4

External surface dimensions:

2 Area of a spherical segment 1.15 cm

2 Area of the pair of spherical segments 2.30 cm

2 Area of the lateral surface 0.30 cm

2 total surfaces 2.60 cm

(b) Application of the release rate controlling membrane To apply the drug release controlling membrane, the following products were used:

Low permeability acrylic polymer 4.5 g

(Eudragit ® RS, Röhm Pharma)

High Permeability Acrylic Polymer 18.2 g

(Eudragit ^ Rl, Röhm Pharma)

Castor oil 0.6 g

Acetone 110 ml

Isopropanol 110 ml

The membrane that controls the release rate was in a pan The polymer solution is sprayed on in short bursts with subsequent drying intervals with cold air.

The layer thickness of the membrane controlling the release rate was

0.06 mm corresponds to 5.4 mg coating / cm of the surface of the biconvex solid matrix-type reservoirs.

(c) Applying the protective membrane

In order to apply the protective membrane, the following products used:

Hydroxypropyl methyl cellulose 3.0 g

(Pharmacoat 606, Shin Etsu Chemical)

Titanium dioxide 1.0 g

Magnesium carbonate 2.5 g

Indomethacin-D, L-lysinate 5.0 g

Solvent mixture 88 ml

(Acetone / isopropanol 1: 1)

The polymer solution was used to apply the protective membrane to the solid matrix-type reservoirs, which were controlled with the rate of release Membrane from the previous treatment stage were provided, coated in a pan.

In the polymer solution for applying the protective membrane, 10% by weight of the total active ingredient was added.

The release of the D, L-lysine salt of indomethacin was both "in vitro" - and in "in vivo" models determined.

" In vitro" model

"In vitro" studies were carried out on (i) the uncoated solid Matrix-type reservoirs and also (ii) carried out on the finished tablets: that is, on the matrix-type reservoirs, coated with the membrane that controls the release rate and with the protective membrane, which contains part of the active ingredient that is used for Immediate availability should be available.

To perform such investigations, a "scrambled" apparatus was the US Pharmacopoeia USPXX used in accordance with distilled water at 37 ⁰ C as the dissolution medium.

The results of the "in vitro" tests were as follows:

Total active ingredient rate release (mg) (mg / hour) 20th 40 54 54 65 43 75 37.5

- 11 -

Α release of D, L-lysine salt of indomethacin from the solid Matrix-type reservoir.

Time (min.)

30 60 90

120

B-release of D, I-lysine salt of indomethacin from the solid Matrix-type reservoir coated with the control of the release rate Membrane and the protective membrane, which contains part of the active ingredient.

Time (hours)

1 2 3 4 5 6

The above results show that the active ingredient from the solid Matrix-type reservoir has been fully released in about 5 hours. After the membrane that controls the release rate is applied and the protective membrane, which contains part of the active ingredient, envelops the tablet, the release rate remains "In vitro" essentially constant over 6 hours, the release rate extending in the range from 12.5 to 15.5 mg / hour.

" In Vivo" Studies

A healthy volunteer test person was given the same tablet, as used in Study B above. The following plasma levels of the active ingredient were determined;

Total active ingredient
release (mg) rate
(mg / hour) 14th 14th 25th 12.5 40 13.3 57 14.25 77 15.4 93 15.5

Time (hours) mcg / ml

1 1.6

2 '2.5 5 3.2 8 1.5

12 1.1

24 0.8

Pharmacological properties

Pharmacological tests were carried out to determine the activity of the Compare compound of the invention to indomethacin activity.

The test procedures and the associated results are given below:

(1) 1-DcQ in mice

Swiss albino mice of both sexes with body weights of 23-25 g were used. 5% strength by weight aqueous solutions or Suspensions in gum arabic of the substances to be tested were administered by means of a stomach tube. The same procedure was followed used for administration by the intraperitoneal route.

LDc-Q was calculated using the Spearman-Karber method. 95% reference limits are reported.

(2) LD ₅₀ on rats

Albino Sprague-Dawley rats of both sexes with body weights from 200 to 210 g were used. 5% strength by weight aqueous Solutions or suspensions in gum arabic of the compounds to be tested were prepared.

(3) Ulcerogenic Activity

Male Sprague-Dawley rats with body weights of about 200 g were used. 5% strength by weight aqueous solutions or

"_ _Λ _ '" ■■ "353127S

Suspensions in gum arabic of the compounds to be tested were prepared. The test procedure described by Shriver D.A., White CB., Sandor A. and Rosenthal M.E. in Toxicology and Applied Pharmacology 352., 73, 1975 was used.

The gastric lesions were scored according to the following scale:

0 no lesion

1 hemorrhagic redness

2 numerous small ulcerations

3 large ulcer and some ulceration

4 numerous large ulcerations

5 perforated ulcer or death of the animal

(4) anti-inflammatory activity Carrageenin induced edema test

The test was carried out on male Sprague-Dawley rats weighing 180-200 g. Groups of 3 animals were given 1, 2, 4 »8 mg / kg of the compounds to be tested. The doses of the compounds were dissolved or suspended in 10 ml of water.

A group of 5 rats (controls) received tap water. All animals were fasted in the morning. After one hour, the volume of the right hind leg was measured. The animals, those that deviated too far from the average were eliminated. Immediately afterwards the connections were made administered via a nasogastric tube. Carrageenin was injected (0.1 ml of a 2% saline solution) into the tarsal zone between the tarsus and the toes of the right hind leg one hour after the compound to be tested has been administered. A uniform distribution of the carrageenin solution in the subcutaneous Tissue was reached through a careful massage. The measurement of the hind leg volume was made 5 hours later repeated.

Edema percentage inhibition was calculated by comparing the hind leg volume increase of each experimental group with

- 14 the value of the control group (was set equal to 100).

(5) Analgesic activity

The acetic acid induced stretching or writhing test (Witkin L.B., Huebner, S.F., Galdi F., O'Keefe E., Spitaletta P., Plummer A.J., J. Pharmacol. Exp. Therap., 133, 400, 1961) was with male Albino Swiss mice weighing 30-40 g.

On the first day of the test, those mice that were not were sorted out less than 20 and not more than 50 flexures in 5 to 20 minutes after i.p. Injection of 0.35 ml of 0.6% acetic acid showed.

The mean number of responses was 32.7 turns in 15 minutes. The animals were then divided into experimental groups, those on the second day of the test with either indomethacin or the D, L-lysine salt of indomethacin at doses of 1, 2, 4 and 8 mg / kg were injected subcutaneously. The compounds were dissolved in deionized water; a 5 normal sodium hydroxide solution was added dropwise to the indomethacin solution until the undissolved residue disappeared.

20 minutes later, each animal was injected with 0.35 ml of 0.6% acetic acid; Five minutes after the injection, the curvatures of each mouse were counted in 15 minutes.

The average number of writhes, for each group of mice was compared to the average number of curvatures observed on the first day of the test (32.7 equals 100 set) to be able to calculate the percentage of inhibition of stretching or curving that was tested by each dose of each Connection is effected.

The results of the tests described above were as follows: LDcQ in mice, oral

Indomethacin 19.03 mg / kg

D, L-lysine salt of indomethacin 38.05 mg / kg

IDcο

on mice, i.p.

Indomethacin D, L-lysine salt of indomethacin

-Q on rats, orally ~~ indomethacin

D, L-lysine salt of indomethacin

38.5 mg / kg
76.11 mg / kg

16.32 mg / kg 24.68 mg / kg

on rats, i «p.

Indomethacin D, L-lysine salt of indomethacin 10.26 mg / kg 18.35 mg / kg

Ulcerogenic activity ; Indomethacin: DU D, L-lysine salt of indomethacin: DU 3.98 mg / kg 6.87 mg / kg

Carrageenin Induced Edema :

Indomethacin: DE.

33 4.27 mg / kg 0.012 mM / kg

D, L-lysine salt of indomethacin: DE «, 3.24 mg / kg 0.006 mM / kg

Analytical activity : indomethacin:

D, L-Ly s ins al ζ from Indomethacin:

8.92 mg / kg 8.13 mg / kg

Claims (4)

Claims 1. D, L-lysine salt of 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3-acetic acid of formula A NH ₂ -CH ₂ - ( COOH NH, (I) (II) wherein (I) is the anion of said acid and (II) is the cation of D, L-lysine. 2. A process for the preparation of the compound mentioned in claim 1 of the formula A, characterized in that equimolar amounts of 1- (4-chlorobenzoyl) -5-methoxy-2-methyl-1H-indole-3-acetic acid and D, L-lysine base are brought into contact in a reaction solvent, whereby a crude product of the compound of formula (A) is obtained, which is separated from the reaction solvent, washed and dried in vacuo, 3. The method according to claim 2, characterized in that the compound obtained is dissolved in a hydroalcoholic phase, the temperature of the resulting solution is brought to about 60 to 80 ⁰ C and then the solution is quickly to 10 to 5 ° C with vigorous stirring is cooled to give micronized crystals of the compound of formula (A), which are separated, washed and dried in vacuo. 4. Orally or parenterally administrable pharmaceutical preparation with anti-inflammatory, antipyretic and analgesic Activities for the therapeutic treatment of rheumatoid arthritis, Bechterew's disease ¹ (ankylosing spondylitis), gouty arthritis, osteoarthritis with a therapeutically effective amount of the compound of formula A as active ingredient and pharmacologically acceptable binders and excipients.